Commit Graph

4412 Commits

Author SHA1 Message Date
Steven Rostedt (VMware) d0cd871ba0 tracing: Have histogram code pass around trace_array for error handling
Have the trace_array that associates the trace instance of the histogram
passed around to functions so that error handling can display the error
message in the proper instance.

Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-08 09:22:38 -04:00
Steven Rostedt (VMware) 1e144d73f7 tracing: Add trace_array parameter to create_event_filter()
Pass in the trace_array that represents the instance the filter being
changed is in to create_event_filter(). This will allow for error messages
that happen when writing to the filter can be displayed in the proper
instance "error_log" file.

Note, for calls to create_filter() (that was also modified to support
create_event_filter()), that changes filters that do not exist in a instance
(for perf for example), NULL may be passed in, which means that there will
not be any message to log for that filter.

Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-08 09:22:28 -04:00
Uwe Kleine-König 12f2639038 tracing: stop making gpio tracing configurable
gpio tracing was made configurable in 4.4-rc1 (commit ddd70280bf
("tracing: gpio: Add Kconfig option for enabling/disabling trace
events")). Since then it is the only event type that can be compiled
conditionally. Given that there is only little overhead I don't
understand the reasoning and I was annoyed more than once that gpio
events were not available without recompiling.

So drop the Kconfig symbol and make gpio events available
unconditionally.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-04-08 15:11:48 +02:00
Steven Rostedt (Red Hat) b35f549df1 syscalls: Remove start and number from syscall_get_arguments() args
At Linux Plumbers, Andy Lutomirski approached me and pointed out that the
function call syscall_get_arguments() implemented in x86 was horribly
written and not optimized for the standard case of passing in 0 and 6 for
the starting index and the number of system calls to get. When looking at
all the users of this function, I discovered that all instances pass in only
0 and 6 for these arguments. Instead of having this function handle
different cases that are never used, simply rewrite it to return the first 6
arguments of a system call.

This should help out the performance of tracing system calls by ptrace,
ftrace and perf.

Link: http://lkml.kernel.org/r/20161107213233.754809394@goodmis.org

Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Dave Martin <dave.martin@arm.com>
Cc: "Dmitry V. Levin" <ldv@altlinux.org>
Cc: x86@kernel.org
Cc: linux-snps-arc@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: uclinux-h8-devel@lists.sourceforge.jp
Cc: linux-hexagon@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Cc: nios2-dev@lists.rocketboards.org
Cc: openrisc@lists.librecores.org
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-riscv@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Cc: linux-um@lists.infradead.org
Cc: linux-xtensa@linux-xtensa.org
Cc: linux-arch@vger.kernel.org
Acked-by: Paul Burton <paul.burton@mips.com> # MIPS parts
Acked-by: Max Filippov <jcmvbkbc@gmail.com> # For xtensa changes
Acked-by: Will Deacon <will.deacon@arm.com> # For the arm64 bits
Reviewed-by: Thomas Gleixner <tglx@linutronix.de> # for x86
Reviewed-by: Dmitry V. Levin <ldv@altlinux.org>
Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-05 09:26:43 -04:00
Steven Rostedt (Red Hat) d08e411397 tracing/syscalls: Pass in hardcoded 6 into syscall_get_arguments()
The only users that calls syscall_get_arguments() with a variable and not a
hard coded '6' is ftrace_syscall_enter(). syscall_get_arguments() can be
optimized by removing a variable input, and always grabbing 6 arguments
regardless of what the system call actually uses.

Change ftrace_syscall_enter() to pass the 6 args into a local stack array
and copy the necessary arguments into the trace event as needed.

This is needed to remove two parameters from syscall_get_arguments().

Link: http://lkml.kernel.org/r/20161107213233.627583542@goodmis.org

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-04 09:17:52 -04:00
Peter Zijlstra 4a6c91fbde x86/uaccess, ftrace: Fix ftrace_likely_update() vs. SMAP
For CONFIG_TRACE_BRANCH_PROFILING=y the likely/unlikely things get
overloaded and generate callouts to this code, and thus also when
AC=1.

Make it safe.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-03 11:02:24 +02:00
Masami Hiramatsu ab105a4fb8 tracing: Use tracing error_log with probe events
Use tracing error_log with probe events for logging error more
precisely. This also makes all parse error returns -EINVAL
(except for -ENOMEM), because user can see better error message
in error_log file now.

Link: http://lkml.kernel.org/r/6a4d90e141d138040ea61f4776b991597077451e.1554072478.git.tom.zanussi@linux.intel.com

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-02 18:24:07 -04:00
Tom Zanussi 34f76afaac tracing: Use tracing error_log with trace event filters
Use tracing_log_err() from the new tracing error_log mechanism to send
filter parse errors to tracing/error_log.

With this change, users will be able to see filter errors by looking
at tracing/error_log.

The same errors will also be available in the filter file, as
expected.

Link: http://lkml.kernel.org/r/1d942c419941539a11d78a6810fc5740a99b2974.1554072478.git.tom.zanussi@linux.intel.com

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-02 18:24:07 -04:00
Tom Zanussi d566c5e9d1 tracing: Use tracing error_log with hist triggers
Replace hist_err() and hist_err_event() with tracing_log_err() from
the new tracing error_log mechanism.

Also add a couple related helper functions and remove most of the old
hist_err()-related code.

With this change, users no longer read the hist files for hist trigger
error information, but instead look at tracing/error_log for the same
information.

Link: http://lkml.kernel.org/r/c98f77a97c9715d18b623eeb5741057b330d5ac0.1554072478.git.tom.zanussi@linux.intel.com

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-02 18:24:07 -04:00
Tom Zanussi a1a05bb40e tracing: Save the last hist command's associated event name
In preparation for making use of the new trace error log, save the
subsystem and event name associated with the last hist command - it
will be passed as the location param in the event_log_err() calls.

Link: http://lkml.kernel.org/r/eb0fd1362be8f39facb86c83eecf441b7a5876f8.1554072478.git.tom.zanussi@linux.intel.com

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-02 18:24:07 -04:00
Tom Zanussi 8a062902be tracing: Add tracing error log
Introduce a new ftrace file, tracing/error_log, for ftrace commands to
log errors.  This is useful for allowing more complex commands such as
hist trigger and kprobe_event commands to point out specifically where
something may have gone wrong without forcing them to resort to more
ad hoc methods such as tacking error messages onto existing output
files.

To log a tracing error, call the event_log_err() function, passing it
a location string describing where it came from e.g. kprobe_events or
system:event, the command that caused the error, an array of static
error strings describing errors and an index within that array which
describes the specific error, along with the position to place the
error caret.

Reading the log displays the last (currently) 8 errors logged in the
following format:

  [timestamp] <loc>: error: <static error text>
    Command: <command that caused the error>
                      ^

Memory for the error log isn't allocated unless there has been a trace
event error, and the error log can be cleared and have its memory
freed by writing the empty string in truncation mode to it:

  # echo > tracing/error_log.

Link: http://lkml.kernel.org/r/0c2c82571fd38c5f3a88ca823627edff250e9416.1554072478.git.tom.zanussi@linux.intel.com

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Suggested-by: Masami Hiramatsu <mhiramat@kernel.org>
Improvements-suggested-by: Steve Rostedt <rostedt@goodmis.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-02 18:24:06 -04:00
Divya Indi f45d1225ad tracing: Kernel access to Ftrace instances
Ftrace provides the feature “instances” that provides the capability to
create multiple Ftrace ring buffers. However, currently these buffers
are created/accessed via userspace only. The kernel APIs providing these
features are not exported, hence cannot be used by other kernel
components.

This patch aims to extend this infrastructure to provide the
flexibility to create/log/remove/ enable-disable existing trace events
to these buffers from within the kernel.

Link: http://lkml.kernel.org/r/1553106531-3281-2-git-send-email-divya.indi@oracle.com

Signed-off-by: Divya Indi <divya.indi@oracle.com>
Reviewed-by: Joe Jin <joe.jin@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-02 18:24:06 -04:00
YueHaibing 40ed29b373 ring-buffer: Fix ring buffer size in rb_write_something()
'cnt' should be used to calculate ring buffer size rather than data->cnt

Link: http://lkml.kernel.org/r/1537704693-184237-1-git-send-email-yuehaibing@huawei.com

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-02 18:24:06 -04:00
Hariprasad Kelam 9efb85c5cf ftrace: Fix warning using plain integer as NULL & spelling corrections
Changed  0 --> NULL to avoid sparse warning
Corrected spelling mistakes reported by checkpatch.pl
Sparse warning below:

sudo make C=2 CF=-D__CHECK_ENDIAN__ M=kernel/trace

CHECK   kernel/trace/ftrace.c
kernel/trace/ftrace.c:3007:24: warning: Using plain integer as NULL pointer
kernel/trace/ftrace.c:4758:37: warning: Using plain integer as NULL pointer

Link: http://lkml.kernel.org/r/20190323183523.GA2244@hari-Inspiron-1545

Signed-off-by: Hariprasad Kelam <hariprasad.kelam@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-26 08:35:36 -04:00
Frank Rowand 3dee10da2e tracing: initialize variable in create_dyn_event()
Fix compile warning in create_dyn_event(): 'ret' may be used uninitialized
in this function [-Wuninitialized].

Link: http://lkml.kernel.org/r/1553237900-8555-1-git-send-email-frowand.list@gmail.com

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Fixes: 5448d44c38 ("tracing: Add unified dynamic event framework")
Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-26 08:35:36 -04:00
Tom Zanussi ff9d31d0d4 tracing: Remove unnecessary var_ref destroy in track_data_destroy()
Commit 656fe2ba85 (tracing: Use hist trigger's var_ref array to
destroy var_refs) centralized the destruction of all the var_refs
in one place so that other code didn't have to do it.

The track_data_destroy() added later ignored that and also destroyed
the track_data var_ref, causing a double-free error flagged by KASAN.

==================================================================
BUG: KASAN: use-after-free in destroy_hist_field+0x30/0x70
Read of size 8 at addr ffff888086df2210 by task bash/1694

CPU: 6 PID: 1694 Comm: bash Not tainted 5.1.0-rc1-test+ #15
Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03
07/14/2016
Call Trace:
 dump_stack+0x71/0xa0
 ? destroy_hist_field+0x30/0x70
 print_address_description.cold.3+0x9/0x1fb
 ? destroy_hist_field+0x30/0x70
 ? destroy_hist_field+0x30/0x70
 kasan_report.cold.4+0x1a/0x33
 ? __kasan_slab_free+0x100/0x150
 ? destroy_hist_field+0x30/0x70
 destroy_hist_field+0x30/0x70
 track_data_destroy+0x55/0xe0
 destroy_hist_data+0x1f0/0x350
 hist_unreg_all+0x203/0x220
 event_trigger_open+0xbb/0x130
 do_dentry_open+0x296/0x700
 ? stacktrace_count_trigger+0x30/0x30
 ? generic_permission+0x56/0x200
 ? __x64_sys_fchdir+0xd0/0xd0
 ? inode_permission+0x55/0x200
 ? security_inode_permission+0x18/0x60
 path_openat+0x633/0x22b0
 ? path_lookupat.isra.50+0x420/0x420
 ? __kasan_kmalloc.constprop.12+0xc1/0xd0
 ? kmem_cache_alloc+0xe5/0x260
 ? getname_flags+0x6c/0x2a0
 ? do_sys_open+0x149/0x2b0
 ? do_syscall_64+0x73/0x1b0
 ? entry_SYSCALL_64_after_hwframe+0x44/0xa9
 ? _raw_write_lock_bh+0xe0/0xe0
 ? __kernel_text_address+0xe/0x30
 ? unwind_get_return_address+0x2f/0x50
 ? __list_add_valid+0x2d/0x70
 ? deactivate_slab.isra.62+0x1f4/0x5a0
 ? getname_flags+0x6c/0x2a0
 ? set_track+0x76/0x120
 do_filp_open+0x11a/0x1a0
 ? may_open_dev+0x50/0x50
 ? _raw_spin_lock+0x7a/0xd0
 ? _raw_write_lock_bh+0xe0/0xe0
 ? __alloc_fd+0x10f/0x200
 do_sys_open+0x1db/0x2b0
 ? filp_open+0x50/0x50
 do_syscall_64+0x73/0x1b0
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fa7b24a4ca2
Code: 25 00 00 41 00 3d 00 00 41 00 74 4c 48 8d 05 85 7a 0d 00 8b 00 85 c0
75 6d 89 f2 b8 01 01 00 00 48 89 fe bf 9c ff ff ff 0f 05 <48> 3d 00 f0 ff ff
0f 87 a2 00 00 00 48 8b 4c 24 28 64 48 33 0c 25
RSP: 002b:00007fffbafb3af0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 000055d3648ade30 RCX: 00007fa7b24a4ca2
RDX: 0000000000000241 RSI: 000055d364a55240 RDI: 00000000ffffff9c
RBP: 00007fffbafb3bf0 R08: 0000000000000020 R09: 0000000000000002
R10: 00000000000001b6 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000003 R14: 0000000000000001 R15: 000055d364a55240
==================================================================

So remove the track_data_destroy() destroy_hist_field() call for that
var_ref.

Link: http://lkml.kernel.org/r/1deffec420f6a16d11dd8647318d34a66d1989a9.camel@linux.intel.com

Fixes: 466f4528fb ("tracing: Generalize hist trigger onmax and save action")
Reported-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-26 08:34:00 -04:00
Linus Torvalds 11efae3506 for-5.1/block-post-20190315
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Merge tag 'for-5.1/block-post-20190315' of git://git.kernel.dk/linux-block

Pull more block layer changes from Jens Axboe:
 "This is a collection of both stragglers, and fixes that came in after
  I finalized the initial pull. This contains:

   - An MD pull request from Song, with a few minor fixes

   - Set of NVMe patches via Christoph

   - Pull request from Konrad, with a few fixes for xen/blkback

   - pblk fix IO calculation fix (Javier)

   - Segment calculation fix for pass-through (Ming)

   - Fallthrough annotation for blkcg (Mathieu)"

* tag 'for-5.1/block-post-20190315' of git://git.kernel.dk/linux-block: (25 commits)
  blkcg: annotate implicit fall through
  nvme-tcp: support C2HData with SUCCESS flag
  nvmet: ignore EOPNOTSUPP for discard
  nvme: add proper write zeroes setup for the multipath device
  nvme: add proper discard setup for the multipath device
  nvme: remove nvme_ns_config_oncs
  nvme: disable Write Zeroes for qemu controllers
  nvmet-fc: bring Disconnect into compliance with FC-NVME spec
  nvmet-fc: fix issues with targetport assoc_list list walking
  nvme-fc: reject reconnect if io queue count is reduced to zero
  nvme-fc: fix numa_node when dev is null
  nvme-fc: use nr_phys_segments to determine existence of sgl
  nvme-loop: init nvmet_ctrl fatal_err_work when allocate
  nvme: update comment to make the code easier to read
  nvme: put ns_head ref if namespace fails allocation
  nvme-trace: fix cdw10 buffer overrun
  nvme: don't warn on block content change effects
  nvme: add get-feature to admin cmds tracer
  md: Fix failed allocation of md_register_thread
  It's wrong to add len to sector_nr in raid10 reshape twice
  ...
2019-03-16 12:36:39 -07:00
Linus Torvalds aa2e3ac64a This contains a series of last minute clean ups, small fixes and
error checks.
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Merge tag 'trace-v5.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes and cleanups from Steven Rostedt:
 "This contains a series of last minute clean ups, small fixes and error
  checks"

* tag 'trace-v5.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing/probe: Verify alloc_trace_*probe() result
  tracing/probe: Check event/group naming rule at parsing
  tracing/probe: Check the size of argument name and body
  tracing/probe: Check event name length correctly
  tracing/probe: Check maxactive error cases
  tracing: kdb: Fix ftdump to not sleep
  trace/probes: Remove kernel doc style from non kernel doc comment
  tracing/probes: Make reserved_field_names static
2019-03-15 14:47:02 -07:00
Masami Hiramatsu a039480e9e tracing/probe: Verify alloc_trace_*probe() result
Since alloc_trace_*probe() returns -EINVAL only if !event && !group,
it should not happen in trace_*probe_create(). If we catch that case
there is a bug. So use WARN_ON_ONCE() instead of pr_info().

Link: http://lkml.kernel.org/r/155253785078.14922.16902223633734601469.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-14 19:54:21 -04:00
Masami Hiramatsu 5b7a962209 tracing/probe: Check event/group naming rule at parsing
Check event and group naming rule at parsing it instead
of allocating probes.

Link: http://lkml.kernel.org/r/155253784064.14922.2336893061156236237.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-14 19:54:11 -04:00
Masami Hiramatsu b4443c17a3 tracing/probe: Check the size of argument name and body
Check the size of argument name and expression is not 0
and smaller than maximum length.

Link: http://lkml.kernel.org/r/155253783029.14922.12650939303827581096.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-14 19:53:57 -04:00
Masami Hiramatsu dec65d79fd tracing/probe: Check event name length correctly
Ensure given name of event is not too long when parsing it,
and fix to update event name offset correctly when the group
name is given. For example, this makes probe event to check
the "p:foo/" error case correctly.

Link: http://lkml.kernel.org/r/155253782046.14922.14724124823730168629.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-14 19:53:47 -04:00
Masami Hiramatsu 287c038c0b tracing/probe: Check maxactive error cases
Check maxactive on kprobe error case, because maxactive
is only for kretprobe, not for kprobe. Also, maxactive
should not be 0, it should be at least 1.

Link: http://lkml.kernel.org/r/155253780952.14922.15784129810238750331.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-14 19:53:29 -04:00
Mathieu Malaterre f6d85f04e2 blkcg: annotate implicit fall through
There is a plan to build the kernel with -Wimplicit-fallthrough and
this place in the code produced a warning (W=1).

This commit remove the following warning:

  kernel/trace/blktrace.c:725:9: warning: this statement may fall through [-Wimplicit-fallthrough=]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-03-13 14:31:12 -06:00
Douglas Anderson 31b265b3ba tracing: kdb: Fix ftdump to not sleep
As reported back in 2016-11 [1], the "ftdump" kdb command triggers a
BUG for "sleeping function called from invalid context".

kdb's "ftdump" command wants to call ring_buffer_read_prepare() in
atomic context.  A very simple solution for this is to add allocation
flags to ring_buffer_read_prepare() so kdb can call it without
triggering the allocation error.  This patch does that.

Note that in the original email thread about this, it was suggested
that perhaps the solution for kdb was to either preallocate the buffer
ahead of time or create our own iterator.  I'm hoping that this
alternative of adding allocation flags to ring_buffer_read_prepare()
can be considered since it means I don't need to duplicate more of the
core trace code into "trace_kdb.c" (for either creating my own
iterator or re-preparing a ring allocator whose memory was already
allocated).

NOTE: another option for kdb is to actually figure out how to make it
reuse the existing ftrace_dump() function and totally eliminate the
duplication.  This sounds very appealing and actually works (the "sr
z" command can be seen to properly dump the ftrace buffer).  The
downside here is that ftrace_dump() fully consumes the trace buffer.
Unless that is changed I'd rather not use it because it means "ftdump
| grep xyz" won't be very useful to search the ftrace buffer since it
will throw away the whole trace on the first grep.  A future patch to
dump only the last few lines of the buffer will also be hard to
implement.

[1] https://lkml.kernel.org/r/20161117191605.GA21459@google.com

Link: http://lkml.kernel.org/r/20190308193205.213659-1-dianders@chromium.org

Reported-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-13 09:46:10 -04:00
Linus Torvalds 5f739e4a49 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc vfs updates from Al Viro:
 "Assorted fixes (really no common topic here)"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  vfs: Make __vfs_write() static
  vfs: fix preadv64v2 and pwritev64v2 compat syscalls with offset == -1
  pipe: stop using ->can_merge
  splice: don't merge into linked buffers
  fs: move generic stat response attr handling to vfs_getattr_nosec
  orangefs: don't reinitialize result_mask in ->getattr
  fs/devpts: always delete dcache dentry-s in dput()
2019-03-12 13:27:20 -07:00
Valdis Klētnieks cede666e2e trace/probes: Remove kernel doc style from non kernel doc comment
CC      kernel/trace/trace_kprobe.o
kernel/trace/trace_kprobe.c:41: warning: cannot understand function prototype: 'struct trace_kprobe '

The real problem is that a comment looked like kerneldoc when it shouldn't be...

Link: http://lkml.kernel.org/r/2812.1552381112@turing-police

Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-12 11:23:52 -04:00
Valdis Klētnieks 0841625201 tracing/probes: Make reserved_field_names static
sparse complains:
  CHECK   kernel/trace/trace_probe.c
kernel/trace/trace_probe.c:16:12: warning: symbol 'reserved_field_names' was not declared. Should it be static?

Yes, it should be static.

Link: http://lkml.kernel.org/r/2478.1552380778@turing-police

Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-12 10:59:51 -04:00
Linus Torvalds 6cdfa54cd2 The biggest change for this release is in the histogram code.
- Add "onchange(var)" histogram handler that executes a action when $var
    changes.
 
  - Add new "snapshot()" action for histogram handlers, that causes a
    snapshot of the ring buffer when triggered.
    ie. onchange(var).snapshot() will trigger a snapshot if var changes.
 
  - Add alternative for "trace()" action.
    Currently, to trigger a synthetic event, the name of that event is used
    as the handler name, which is inconsistent with the other actions.
    onchange(var).synthetic(param) where it can now be
    onchange(var).trace(synthetic, param). The older method will still be
    allowed, as long as the synthetic events do not overlap with other
    handler names.
 
  - The histogram documentation at testcases were updated for the new
    changes.
 
 Added a quicker way to enable set_ftrace_filter files, that will make
 it much quicker to bisect tracing a function that shouldn't be traced and
 crashes the kernel. (You can echo in numbers to set_ftrace_filter, and it
 will select the corresponding function that is in
 available_filter_functions).
 
 Some better displaying of the tracing data (and more information was added).
 
 The rest are small fixes and more clean ups to the code.
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Merge tag 'trace-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "The biggest change for this release is in the histogram code:

   - Add "onchange(var)" histogram handler that executes a action when
     $var changes.

   - Add new "snapshot()" action for histogram handlers, that causes a
     snapshot of the ring buffer when triggered. ie.
     onchange(var).snapshot() will trigger a snapshot if var changes.

   - Add alternative for "trace()" action. Currently, to trigger a
     synthetic event, the name of that event is used as the handler
     name, which is inconsistent with the other actions.
     onchange(var).synthetic(param) where it can now be
     onchange(var).trace(synthetic, param). The older method will still
     be allowed, as long as the synthetic events do not overlap with
     other handler names.

   - The histogram documentation at testcases were updated for the new
     changes.

  Outside of the histogram code, we have:

   - Added a quicker way to enable set_ftrace_filter files, that will
     make it much quicker to bisect tracing a function that shouldn't be
     traced and crashes the kernel. (You can echo in numbers to
     set_ftrace_filter, and it will select the corresponding function
     that is in available_filter_functions).

   - Some better displaying of the tracing data (and more information
     was added).

  The rest are small fixes and more clean ups to the code"

* tag 'trace-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (37 commits)
  tracing: Use strncpy instead of memcpy when copying comm in trace.c
  tracing: Use strncpy instead of memcpy when copying comm for hist triggers
  tracing: Use strncpy instead of memcpy for string keys in hist triggers
  tracing: Use str_has_prefix() in synth_event_create()
  x86/ftrace: Fix warning and considate ftrace_jmp_replace() and ftrace_call_replace()
  tracing/perf: Use strndup_user() instead of buggy open-coded version
  doc: trace: Fix documentation for uprobe_profile
  tracing: Fix spelling mistake: "analagous" -> "analogous"
  tracing: Comment why cond_snapshot is checked outside of max_lock protection
  tracing: Add hist trigger action 'expected fail' test case
  tracing: Add alternative synthetic event trace action test case
  tracing: Add hist trigger onchange() handler test case
  tracing: Add hist trigger snapshot() action test case
  tracing: Add SPDX license GPL-2.0 license identifier to inter-event testcases
  tracing: Add alternative synthetic event trace action syntax
  tracing: Add hist trigger onchange() handler Documentation
  tracing: Add hist trigger onchange() handler
  tracing: Add hist trigger snapshot() action Documentation
  tracing: Add hist trigger snapshot() action
  tracing: Add conditional snapshot
  ...
2019-03-11 17:01:32 -07:00
Linus Torvalds ffd602eb46 Kbuild updates for v5.1
- do not generate unneeded top-level built-in.a
 
  - let git ignore O= directory entirely
 
  - optimize scripts/kallsyms slightly
 
  - exclude DWARF info from *.s regardless of config options
 
  - fix GCC toolchain search path for Clang to prepare ld.lld support
 
  - do not generate modules.order when CONFIG_MODULES is disabled
 
  - simplify single target rules and remove VPATH for external module build
 
  - allow to add optional flags to dpkg-buildpackage when building deb-pkg
 
  - move some compiler option tests from Makefile to Kconfig
 
  - various Makefile cleanups
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Merge tag 'kbuild-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - do not generate unneeded top-level built-in.a

 - let git ignore O= directory entirely

 - optimize scripts/kallsyms slightly

 - exclude DWARF info from *.s regardless of config options

 - fix GCC toolchain search path for Clang to prepare ld.lld support

 - do not generate modules.order when CONFIG_MODULES is disabled

 - simplify single target rules and remove VPATH for external module
   build

 - allow to add optional flags to dpkg-buildpackage when building
   deb-pkg

 - move some compiler option tests from Makefile to Kconfig

 - various Makefile cleanups

* tag 'kbuild-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (40 commits)
  kbuild: remove scripts/basic/% build target
  kbuild: use -Werror=implicit-... instead of -Werror-implicit-...
  kbuild: clean up scripts/gcc-version.sh
  kbuild: remove cc-version macro
  kbuild: update comment block of scripts/clang-version.sh
  kbuild: remove commented-out INITRD_COMPRESS
  kbuild: move -gsplit-dwarf, -gdwarf-4 option tests to Kconfig
  kbuild: [bin]deb-pkg: add DPKG_FLAGS variable
  kbuild: move ".config not found!" message from Kconfig to Makefile
  kbuild: invoke syncconfig if include/config/auto.conf.cmd is missing
  kbuild: simplify single target rules
  kbuild: remove empty rules for makefiles
  kbuild: make -r/-R effective in top Makefile for old Make versions
  kbuild: move tools_silent to a more relevant place
  kbuild: compute false-positive -Wmaybe-uninitialized cases in Kconfig
  kbuild: refactor cc-cross-prefix implementation
  kbuild: hardcode genksyms path and remove GENKSYMS variable
  scripts/gdb: refactor rules for symlink creation
  kbuild: create symlink to vmlinux-gdb.py in scripts_gdb target
  scripts/gdb: do not descend into scripts/gdb from scripts
  ...
2019-03-10 17:48:21 -07:00
Linus Torvalds bdfa15f1a3 One small fix and one clean up
A small fix Pavel sent me back in august was accidentally lost due to it
 being placed with some other patches that failed some tests, and was rebased
 out of my local tree. Which was a regression that caused event filters
 not to handle negative numbers.
 
 The clean up is from Masami that realized that the code in kprobes that
 calls probe_mem_read() wrapper, which is to be used in code used by both
 kprobes and uprobes, was only in code for kprobes. It should not use the
 wrapper there, but instead call probe_kernel_read() directly.
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Merge tag 'trace-v5.0-pre' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix/cleanup from Steven Rostedt:
 "This is a "pre-pull". It's only one small fix and one small clean up.
  I'm testing a few small patches for my real pull request which will
  come at a later time. The second patch depends on your tree anyway so
  I included it along with the urgent fix.

  A small fix Pavel sent me back in august was accidentally lost due to
  it being placed with some other patches that failed some tests, and
  was rebased out of my local tree. Which was a regression that caused
  event filters not to handle negative numbers.

  The clean up is from Masami that realized that the code in kprobes
  that calls probe_mem_read() wrapper, which is to be used in code used
  by both kprobes and uprobes, was only in code for kprobes. It should
  not use the wrapper there, but instead call probe_kernel_read()
  directly"

* tag 'trace-v5.0-pre' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing/kprobes: Use probe_kernel_read instead of probe_mem_read
  tracing: Fix event filters and triggers to handle negative numbers
2019-03-07 09:55:56 -08:00
Tom Zanussi 85f726a35e tracing: Use strncpy instead of memcpy when copying comm in trace.c
Because there may be random garbage beyond a string's null terminator,
code that might use the entire comm array e.g. histogram keys, can
give unexpected results if that garbage is copied in too, so avoid
that possibility by using strncpy instead of memcpy.

Link: http://lkml.kernel.org/r/1d6ebac26570c2a29ce9fb575379f17ef5c8b81b.1551802084.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Suggested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-05 12:14:42 -05:00
Tom Zanussi 27242c62b1 tracing: Use strncpy instead of memcpy when copying comm for hist triggers
Because there may be random garbage beyond a string's null terminator,
code that might use the entire comm array e.g. histogram keys, can
give unexpected results if that garbage is copied in too, so avoid
that possibility by using strncpy instead of memcpy.

Link: http://lkml.kernel.org/r/1eb9f096a8086c3c82c7fc087c900005143cec54.1551802084.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-05 12:14:28 -05:00
Tom Zanussi 9f0bbf3115 tracing: Use strncpy instead of memcpy for string keys in hist triggers
Because there may be random garbage beyond a string's null terminator,
it's not correct to copy the the complete character array for use as a
hist trigger key.  This results in multiple histogram entries for the
'same' string key.

So, in the case of a string key, use strncpy instead of memcpy to
avoid copying in the extra bytes.

Before, using the gdbus entries in the following hist trigger as an
example:

  # echo 'hist:key=comm' > /sys/kernel/debug/tracing/events/sched/sched_waking/trigger
  # cat /sys/kernel/debug/tracing/events/sched/sched_waking/hist

  ...

  { comm: ImgDecoder #4                      } hitcount:        203
  { comm: gmain                              } hitcount:        213
  { comm: gmain                              } hitcount:        216
  { comm: StreamTrans #73                    } hitcount:        221
  { comm: mozStorage #3                      } hitcount:        230
  { comm: gdbus                              } hitcount:        233
  { comm: StyleThread#5                      } hitcount:        253
  { comm: gdbus                              } hitcount:        256
  { comm: gdbus                              } hitcount:        260
  { comm: StyleThread#4                      } hitcount:        271

  ...

  # cat /sys/kernel/debug/tracing/events/sched/sched_waking/hist | egrep gdbus | wc -l
  51

After:

  # cat /sys/kernel/debug/tracing/events/sched/sched_waking/hist | egrep gdbus | wc -l
  1

Link: http://lkml.kernel.org/r/50c35ae1267d64eee975b8125e151e600071d4dc.1549309756.git.tom.zanussi@linux.intel.com

Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org
Fixes: 79e577cbce ("tracing: Support string type key properly")
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-05 08:47:46 -05:00
Tom Zanussi ed581aaf99 tracing: Use str_has_prefix() in synth_event_create()
Since we now have a str_has_prefix() that returns the length, we can
use that instead of explicitly calculating it.

Link: http://lkml.kernel.org/r/03418373fd1e80030e7394b8e3e081c5de28a710.1549309756.git.tom.zanussi@linux.intel.com

Cc: Joe Perches <joe@perches.com>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-05 08:47:46 -05:00
Masami Hiramatsu 49ef5f4570 tracing/kprobes: Use probe_kernel_read instead of probe_mem_read
Use probe_kernel_read() instead of probe_mem_read() because
probe_mem_read() is a kind of wrapper for switching memory
read function between uprobes and kprobes.

Link: http://lkml.kernel.org/r/20190222011643.3e19ade84a3db3e83518648f@kernel.org

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-01 16:18:15 -05:00
Pavel Tikhomirov 6a072128d2 tracing: Fix event filters and triggers to handle negative numbers
Then tracing syscall exit event it is extremely useful to filter exit
codes equal to some negative value, to react only to required errors.
But negative numbers does not work:

[root@snorch sys_exit_read]# echo "ret == -1" > filter
bash: echo: write error: Invalid argument
[root@snorch sys_exit_read]# cat filter
ret == -1
        ^
parse_error: Invalid value (did you forget quotes)?

Similar thing happens when setting triggers.

These is a regression in v4.17 introduced by the commit mentioned below,
testing without these commit shows no problem with negative numbers.

Link: http://lkml.kernel.org/r/20180823102534.7642-1-ptikhomirov@virtuozzo.com

Cc: stable@vger.kernel.org
Fixes: 80765597bc ("tracing: Rewrite filter logic to be simpler and faster")
Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-01 16:11:09 -05:00
Ingo Molnar 9ed8f1a6e7 Merge branch 'linus' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-28 08:27:17 +01:00
Masahiro Yamada b303c6df80 kbuild: compute false-positive -Wmaybe-uninitialized cases in Kconfig
Since -Wmaybe-uninitialized was introduced by GCC 4.7, we have patched
various false positives:

 - commit e74fc973b6 ("Turn off -Wmaybe-uninitialized when building
   with -Os") turned off this option for -Os.

 - commit 815eb71e71 ("Kbuild: disable 'maybe-uninitialized' warning
   for CONFIG_PROFILE_ALL_BRANCHES") turned off this option for
   CONFIG_PROFILE_ALL_BRANCHES

 - commit a76bcf557e ("Kbuild: enable -Wmaybe-uninitialized warning
   for "make W=1"") turned off this option for GCC < 4.9
   Arnd provided more explanation in https://lkml.org/lkml/2017/3/14/903

I think this looks better by shifting the logic from Makefile to Kconfig.

Link: https://github.com/ClangBuiltLinux/linux/issues/350
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
2019-02-27 21:43:20 +09:00
Jann Horn 83540fbc88 tracing/perf: Use strndup_user() instead of buggy open-coded version
The first version of this method was missing the check for
`ret == PATH_MAX`; then such a check was added, but it didn't call kfree()
on error, so there was still a small memory leak in the error case.
Fix it by using strndup_user() instead of open-coding it.

Link: http://lkml.kernel.org/r/20190220165443.152385-1-jannh@google.com

Cc: Ingo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org
Fixes: 0eadcc7a7b ("perf/core: Fix perf_uprobe_init()")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-21 10:35:10 -05:00
Colin Ian King 9e5a36a337 tracing: Fix spelling mistake: "analagous" -> "analogous"
There is a spelling mistake in the mini-howto help text. Fix it.

Link: http://lkml.kernel.org/r/20190217223222.16479-1-colin.king@canonical.com

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-20 13:51:08 -05:00
Steven Rostedt (VMware) 1c347a94ca tracing: Comment why cond_snapshot is checked outside of max_lock protection
Before setting tr->cond_snapshot, it must be NULL before it can be updated.
It can go to NULL when a trace event hist trigger is created or removed, and
can only be modified under the max_lock spin lock. But because it can only
be set to something other than NULL under both the max_lock spin lock as
well as the trace_types_lock, we can perform the check if it is not NULL
only under the trace_types_lock and fail out without having to grab the
max_lock spin lock.

This is very subtle, and deserves a comment.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-20 13:51:08 -05:00
Tom Zanussi e91eefd731 tracing: Add alternative synthetic event trace action syntax
Add a 'trace(synthetic_event_name, params)' alternative to
synthetic_event_name(params).

Currently, the syntax used for generating synthetic events is to
invoke synthetic_event_name(params) i.e. use the synthetic event name
as a function call.

Users requested a new form that more explicitly shows that the
synthetic event is in effect being traced.  In this version, a new
'trace()' keyword is used, and the synthetic event name is passed in
as the first argument.

In addition, for the sake of consistency with other actions, change
the documention to emphasize the trace() form over the function-call
form, which remains documented as equivalent.

Link: http://lkml.kernel.org/r/d082773e50232a001480cf837679a1e01c1a2eb7.1550100284.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-20 13:51:07 -05:00
Tom Zanussi dff81f5592 tracing: Add hist trigger onchange() handler
Add support for a hist:onchange($var) handler, similar to the onmax()
handler but triggering whenever there's any change in $var, not just a
max.

Link: http://lkml.kernel.org/r/dfbc7e4ada242603e9ec3f049b5ad076a07dfd03.1550100284.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-20 13:51:07 -05:00
Tom Zanussi a3785b7eca tracing: Add hist trigger snapshot() action
Add support for hist:handlerXXX($var).snapshot(), which will take a
snapshot of the current trace buffer whenever handlerXXX is hit.

As a first user, this also adds snapshot() action support for the
onmax() handler i.e. hist:onmax($var).snapshot().

Also, the hist trigger key printing is moved into a separate function
so the snapshot() action can print a histogram key outside the
histogram display - add and use hist_trigger_print_key() for that
purpose.

Link: http://lkml.kernel.org/r/2f1a952c0dcd8aca8702ce81269581a692396d45.1550100284.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-20 13:51:07 -05:00
Tom Zanussi a35873a099 tracing: Add conditional snapshot
Currently, tracing snapshots are context-free - they capture the ring
buffer contents at the time the tracing_snapshot() function was
invoked, and nothing else.  Additionally, they're always taken
unconditionally - the calling code can decide whether or not to take a
snapshot, but the data used to make that decision is kept separately
from the snapshot itself.

This change adds the ability to associate with each trace instance
some user data, along with an 'update' function that can use that data
to determine whether or not to actually take a snapshot.  The update
function can then update that data along with any other state (as part
of the data presumably), if warranted.

Because snapshots are 'global' per-instance, only one user can enable
and use a conditional snapshot for any given trace instance.  To
enable a conditional snapshot (see details in the function and data
structure comments), the user calls tracing_snapshot_cond_enable().
Similarly, to disable a conditional snapshot and free it up for other
users, tracing_snapshot_cond_disable() should be called.

To actually initiate a conditional snapshot, tracing_snapshot_cond()
should be called.  tracing_snapshot_cond() will invoke the update()
callback, allowing the user to decide whether or not to actually take
the snapshot and update the user-defined data associated with the
snapshot.  If the callback returns 'true', tracing_snapshot_cond()
will then actually take the snapshot and return.

This scheme allows for flexibility in snapshot implementations - for
example, by implementing slightly different update() callbacks,
snapshots can be taken in situations where the user is only interested
in taking a snapshot when a new maximum in hit versus when a value
changes in any way at all.  Future patches will demonstrate both
cases.

Link: http://lkml.kernel.org/r/1bea07828d5fd6864a585f83b1eed47ce097eb45.1550100284.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-20 13:51:06 -05:00
Tom Zanussi 466f4528fb tracing: Generalize hist trigger onmax and save action
The action refactor code allowed actions and handlers to be separated,
but the existing onmax handler and save action code is still not
flexible enough to handle arbitrary coupling.  This change generalizes
them and in the process makes additional handlers and actions easier
to implement.

The onmax action can be broken up and thought of as two separate
components - a variable to be tracked (the parameter given to the
onmax($var_to_track) function) and an invisible variable created to
save the ongoing result of doing something with that variable, such as
saving the max value of that variable so far seen.

Separating it out like this and renaming it appropriately allows us to
use the same code for similar tracking functions such as
onchange($var_to_track), which would just track the last value seen
rather than the max seen so far, which is useful in some situations.

Additionally, because different handlers and actions may want to save
and access data differently e.g. save and retrieve tracking values as
local variables vs something more global, save_val() and get_val()
interface functions are introduced and max-specific implementations
are used instead.

The same goes for the code that checks whether a maximum has been hit
- a generic check_val() interface and max-checking implementation is
used instead, which allows future patches to make use of he same code
using their own implemetations of similar functionality.

Link: http://lkml.kernel.org/r/980ea73dd8e3f36db3d646f99652f8fed42b77d4.1550100284.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-20 13:51:06 -05:00
Tom Zanussi c3e49506a0 tracing: Split up onmatch action data
Currently, the onmatch action data binds the onmatch action to data
related to synthetic event generation.  Since we want to allow the
onmatch handler to potentially invoke a different action, and because
we expect other handlers to generate synthetic events, we need to
separate the data related to these two functions.

Also rename the onmatch data to something more descriptive, and create
and use common action data destroy function.

Link: http://lkml.kernel.org/r/b9abbf9aae69fe3920cdc8ddbcaad544dd258d78.1550100284.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-20 13:51:06 -05:00
Tom Zanussi 7d18a10c31 tracing: Refactor hist trigger action code
The hist trigger action code currently implements two essentially
hard-coded pairs of 'actions' - onmax(), which tracks a variable and
saves some event fields when a max is hit, and onmatch(), which is
hard-coded to generate a synthetic event.

These hardcoded pairs (track max/save fields and detect match/generate
synthetic event) should really be decoupled into separate components
that can then be arbitrarily combined.  The first component of each
pair (track max/detect match) is called a 'handler' in the new code,
while the second component (save fields/generate synthetic event) is
called an 'action' in this scheme.

This change refactors the action code to reflect this split by adding
two handlers, HANDLER_ONMATCH and HANDLER_ONMAX, along with two
actions, ACTION_SAVE and ACTION_TRACE.

The new code combines them to produce the existing ONMATCH/TRACE and
ONMAX/SAVE functionality, but doesn't implement the other combinations
now possible.  Future patches will expand these to further useful
cases, such as ONMAX/TRACE, as well as add additional handlers and
actions such as ONCHANGE and SNAPSHOT.

Also, add abbreviated documentation for handlers and actions to
README.

Link: http://lkml.kernel.org/r/98bfdd48c1b4ff29fc5766442f99f5bc3c34b76b.1550100284.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-20 13:51:06 -05:00
zhangyi (F) e7f0c424d0 tracing: Do not free iter->trace in fail path of tracing_open_pipe()
Commit d716ff71dd ("tracing: Remove taking of trace_types_lock in
pipe files") use the current tracer instead of the copy in
tracing_open_pipe(), but it forget to remove the freeing sentence in
the error path.

There's an error path that can call kfree(iter->trace) after the iter->trace
was assigned to tr->current_trace, which would be bad to free.

Link: http://lkml.kernel.org/r/1550060946-45984-1-git-send-email-yi.zhang@huawei.com

Cc: stable@vger.kernel.org
Fixes: d716ff71dd ("tracing: Remove taking of trace_types_lock in pipe files")
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-20 13:47:08 -05:00
Linus Torvalds 10f4902173 Two more tracing fixes
- Have kprobes not use copy_from_user() to access kernel addresses,
    because kprobes can legitimately poke at bad kernel memory, which
    will fault. Copy from user code should never fault in kernel space.
    Using probe_mem_read() can handle kernel address space faulting.
 
  - Put back the entries counter in the tracing output that was accidentally
    removed.
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Merge tag 'trace-v5.0-rc4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Two more tracing fixes

   - Have kprobes not use copy_from_user() to access kernel addresses,
     because kprobes can legitimately poke at bad kernel memory, which
     will fault. Copy from user code should never fault in kernel space.
     Using probe_mem_read() can handle kernel address space faulting.

   - Put back the entries counter in the tracing output that was
     accidentally removed"

* tag 'trace-v5.0-rc4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix number of entries in trace header
  kprobe: Do not use uaccess functions to access kernel memory that can fault
2019-02-18 09:40:16 -08:00
Steven Rostedt (VMware) f79b3f3385 ftrace: Allow enabling of filters via index of available_filter_functions
Enabling of large number of functions by echoing in a large subset of the
functions in available_filter_functions can take a very long time. The
process requires testing all functions registered by the function tracer
(which is in the 10s of thousands), and doing a kallsyms lookup to convert
the ip address into a name, then comparing that name with the string passed
in.

When a function causes the function tracer to crash the system, a binary
bisect of the available_filter_functions can be done to find the culprit.
But this requires passing in half of the functions in
available_filter_functions over and over again, which makes it basically a
O(n^2) operation. With 40,000 functions, that ends up bing 1,600,000,000
opertions! And enabling this can take over 20 minutes.

As a quick speed up, if a number is passed into one of the filter files,
instead of doing a search, it just enables the function at the corresponding
line of the available_filter_functions file. That is:

 # echo 50 > set_ftrace_filter
 # cat set_ftrace_filter
 x86_pmu_commit_txn

 # head -50 available_filter_functions | tail -1
 x86_pmu_commit_txn

This allows setting of half the available_filter_functions to take place in
less than a second!

 # time seq 20000 > set_ftrace_filter
 real    0m0.042s
 user    0m0.005s
 sys     0m0.015s

 # wc -l set_ftrace_filter
 20000 set_ftrace_filter

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-15 13:10:09 -05:00
Quentin Perret 9e7382153f tracing: Fix number of entries in trace header
The following commit

  441dae8f2f ("tracing: Add support for display of tgid in trace output")

removed the call to print_event_info() from print_func_help_header_irq()
which results in the ftrace header not reporting the number of entries
written in the buffer. As this wasn't the original intent of the patch,
re-introduce the call to print_event_info() to restore the orginal
behaviour.

Link: http://lkml.kernel.org/r/20190214152950.4179-1-quentin.perret@arm.com

Acked-by: Joel Fernandes <joelaf@google.com>
Cc: stable@vger.kernel.org
Fixes: 441dae8f2f ("tracing: Add support for display of tgid in trace output")
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-15 12:42:26 -05:00
Changbin Du 2c4f1fcbef kprobe: Do not use uaccess functions to access kernel memory that can fault
The userspace can ask kprobe to intercept strings at any memory address,
including invalid kernel address. In this case, fetch_store_strlen()
would crash since it uses general usercopy function, and user access
functions are no longer allowed to access kernel memory.

For example, we can crash the kernel by doing something as below:

$ sudo kprobe 'p:do_sys_open +0(+0(%si)):string'

[  103.620391] BUG: GPF in non-whitelisted uaccess (non-canonical address?)
[  103.622104] general protection fault: 0000 [#1] SMP PTI
[  103.623424] CPU: 10 PID: 1046 Comm: cat Not tainted 5.0.0-rc3-00130-gd73aba1-dirty #96
[  103.625321] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-2-g628b2e6-dirty-20190104_103505-linux 04/01/2014
[  103.628284] RIP: 0010:process_fetch_insn+0x1ab/0x4b0
[  103.629518] Code: 10 83 80 28 2e 00 00 01 31 d2 31 ff 48 8b 74 24 28 eb 0c 81 fa ff 0f 00 00 7f 1c 85 c0 75 18 66 66 90 0f ae e8 48 63
 ca 89 f8 <8a> 0c 31 66 66 90 83 c2 01 84 c9 75 dc 89 54 24 34 89 44 24 28 48
[  103.634032] RSP: 0018:ffff88845eb37ce0 EFLAGS: 00010246
[  103.635312] RAX: 0000000000000000 RBX: ffff888456c4e5a8 RCX: 0000000000000000
[  103.637057] RDX: 0000000000000000 RSI: 2e646c2f6374652f RDI: 0000000000000000
[  103.638795] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
[  103.640556] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
[  103.642297] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
[  103.644040] FS:  0000000000000000(0000) GS:ffff88846f000000(0000) knlGS:0000000000000000
[  103.646019] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  103.647436] CR2: 00007ffc79758038 CR3: 0000000463360006 CR4: 0000000000020ee0
[  103.649147] Call Trace:
[  103.649781]  ? sched_clock_cpu+0xc/0xa0
[  103.650747]  ? do_sys_open+0x5/0x220
[  103.651635]  kprobe_trace_func+0x303/0x380
[  103.652645]  ? do_sys_open+0x5/0x220
[  103.653528]  kprobe_dispatcher+0x45/0x50
[  103.654682]  ? do_sys_open+0x1/0x220
[  103.655875]  kprobe_ftrace_handler+0x90/0xf0
[  103.657282]  ftrace_ops_assist_func+0x54/0xf0
[  103.658564]  ? __call_rcu+0x1dc/0x280
[  103.659482]  0xffffffffc00000bf
[  103.660384]  ? __ia32_sys_open+0x20/0x20
[  103.661682]  ? do_sys_open+0x1/0x220
[  103.662863]  do_sys_open+0x5/0x220
[  103.663988]  do_syscall_64+0x60/0x210
[  103.665201]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[  103.666862] RIP: 0033:0x7fc22fadccdd
[  103.668034] Code: 48 89 54 24 e0 41 83 e2 40 75 32 89 f0 25 00 00 41 00 3d 00 00 41 00 74 24 89 f2 b8 01 01 00 00 48 89 fe bf 9c ff ff
 ff 0f 05 <48> 3d 00 f0 ff ff 77 33 f3 c3 66 0f 1f 84 00 00 00 00 00 48 8d 44
[  103.674029] RSP: 002b:00007ffc7972c3a8 EFLAGS: 00000287 ORIG_RAX: 0000000000000101
[  103.676512] RAX: ffffffffffffffda RBX: 0000562f86147a21 RCX: 00007fc22fadccdd
[  103.678853] RDX: 0000000000080000 RSI: 00007fc22fae1428 RDI: 00000000ffffff9c
[  103.681151] RBP: ffffffffffffffff R08: 0000000000000000 R09: 0000000000000000
[  103.683489] R10: 0000000000000000 R11: 0000000000000287 R12: 00007fc22fce90a8
[  103.685774] R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000
[  103.688056] Modules linked in:
[  103.689131] ---[ end trace 43792035c28984a1 ]---

This can be fixed by using probe_mem_read() instead, as it can handle faulting
kernel memory addresses, which kprobes can legitimately do.

Link: http://lkml.kernel.org/r/20190125151051.7381-1-changbin.du@gmail.com

Cc: stable@vger.kernel.org
Fixes: 9da3f2b740 ("x86/fault: BUG() when uaccess helpers fault on kernel addresses")
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-15 12:41:23 -05:00
Linus Torvalds b6ea7bcf77 This fixes kprobes/uprobes dynamic processing of strings, where
it processes the args but does not update the remaining length
 of the buffer that the string arguments will be placed in. It
 constantly passes in the total size of buffer used instead of
 passing in the remaining size of the buffer used. This could cause
 issues if the strings are larger than the max size of an event
 which could cause the strings to be written beyond what was reserved
 on the buffer.
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Merge tag 'trace-v5.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "This fixes kprobes/uprobes dynamic processing of strings, where it
  processes the args but does not update the remaining length of the
  buffer that the string arguments will be placed in. It constantly
  passes in the total size of buffer used instead of passing in the
  remaining size of the buffer used.

  This could cause issues if the strings are larger than the max size of
  an event which could cause the strings to be written beyond what was
  reserved on the buffer"

* tag 'trace-v5.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: probeevent: Correctly update remaining space in dynamic area
2019-02-13 10:28:17 -08:00
Masami Hiramatsu eeeb080bae kprobes: Prohibit probing on hardirq tracers
Since kprobes breakpoint handling involves hardirq tracer,
probing these functions cause breakpoint recursion problem.

Prohibit probing on those functions.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrea Righi <righi.andrea@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/154998802073.31052.17255044712514564153.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-13 08:16:40 +01:00
Andreas Ziegler f6675872db tracing: probeevent: Correctly update remaining space in dynamic area
Commit 9178412ddf ("tracing: probeevent: Return consumed
bytes of dynamic area") improved the string fetching
mechanism by returning the number of required bytes after
copying the argument to the dynamic area. However, this
return value is now only used to increment the pointer
inside the dynamic area but misses updating the 'maxlen'
variable which indicates the remaining space in the dynamic
area.

This means that fetch_store_string() always reads the *total*
size of the dynamic area from the data_loc pointer instead of
the *remaining* size (and passes it along to
strncpy_from_{user,unsafe}) even if we're already about to
copy data into the middle of the dynamic area.

Link: http://lkml.kernel.org/r/20190206190013.16405-1-andreas.ziegler@fau.de

Cc: Ingo Molnar <mingo@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 9178412ddf ("tracing: probeevent: Return consumed bytes of dynamic area")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Andreas Ziegler <andreas.ziegler@fau.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-11 15:58:30 -05:00
Changbin Du 85acbb21b9 tracing: Change the function format to display function names by perf
Here is an example for this change.

$ sudo perf record -e 'ftrace:function' --filter='ip==schedule'
$ sudo perf report

The output of perf before this patch:

\# Samples: 100  of event 'ftrace:function'
\# Event count (approx.): 100
\#
\# Overhead  Trace output
\# ........  ......................................
\#
    51.00%   ffffffff81f6aaa0 <-- ffffffff81158e8d
    29.00%   ffffffff81f6aaa0 <-- ffffffff8116ccb2
     8.00%   ffffffff81f6aaa0 <-- ffffffff81f6f2ed
     4.00%   ffffffff81f6aaa0 <-- ffffffff811628db
     4.00%   ffffffff81f6aaa0 <-- ffffffff81f6ec5b
     2.00%   ffffffff81f6aaa0 <-- ffffffff81f6f21a
     1.00%   ffffffff81f6aaa0 <-- ffffffff811b04af
     1.00%   ffffffff81f6aaa0 <-- ffffffff8143ce17

After this patch:

\# Samples: 36  of event 'ftrace:function'
\# Event count (approx.): 36
\#
\# Overhead  Trace output
\# ........  ............................................
\#
    38.89%   schedule <-- schedule_hrtimeout_range_clock
    27.78%   schedule <-- worker_thread
    13.89%   schedule <-- schedule_timeout
    11.11%   schedule <-- smpboot_thread_fn
     5.56%   schedule <-- rcu_gp_kthread
     2.78%   schedule <-- exit_to_usermode_loop

Link: http://lkml.kernel.org/r/20190209161919.32350-1-changbin.du@gmail.com

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-11 14:53:43 -05:00
Linus Torvalds 27b4ad621e Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:
 "This pull request is dedicated to the upcoming snowpocalypse parts 2
  and 3 in the Pacific Northwest:

   1) Drop profiles are broken because some drivers use dev_kfree_skb*
      instead of dev_consume_skb*, from Yang Wei.

   2) Fix IWLWIFI kconfig deps, from Luca Coelho.

   3) Fix percpu maps updating in bpftool, from Paolo Abeni.

   4) Missing station release in batman-adv, from Felix Fietkau.

   5) Fix some networking compat ioctl bugs, from Johannes Berg.

   6) ucc_geth must reset the BQL queue state when stopping the device,
      from Mathias Thore.

   7) Several XDP bug fixes in virtio_net from Toshiaki Makita.

   8) TSO packets must be sent always on queue 0 in stmmac, from Jose
      Abreu.

   9) Fix socket refcounting bug in RDS, from Eric Dumazet.

  10) Handle sparse cpu allocations in bpf selftests, from Martynas
      Pumputis.

  11) Make sure mgmt frames have enough tailroom in mac80211, from Felix
      Feitkau.

  12) Use safe list walking in sctp_sendmsg() asoc list traversal, from
      Greg Kroah-Hartman.

  13) Make DCCP's ccid_hc_[rt]x_parse_options always check for NULL
      ccid, from Eric Dumazet.

  14) Need to reload WoL password into bcmsysport device after deep
      sleeps, from Florian Fainelli.

  15) Remove filter from mask before freeing in cls_flower, from Petr
      Machata.

  16) Missing release and use after free in error paths of s390 qeth
      code, from Julian Wiedmann.

  17) Fix lockdep false positive in dsa code, from Marc Zyngier.

  18) Fix counting of ATU violations in mv88e6xxx, from Andrew Lunn.

  19) Fix EQ firmware assert in qed driver, from Manish Chopra.

  20) Don't default Caivum PTP to Y in kconfig, from Bjorn Helgaas"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (116 commits)
  net: dsa: b53: Fix for failure when irq is not defined in dt
  sit: check if IPv6 enabled before calling ip6_err_gen_icmpv6_unreach()
  geneve: should not call rt6_lookup() when ipv6 was disabled
  net: Don't default Cavium PTP driver to 'y'
  net: broadcom: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: via-velocity: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: tehuti: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: sun: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: fsl_ucc_hdlc: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: fec_mpc52xx: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: smsc: epic100: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: dscc4: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: tulip: de2104x: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net: defxx: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles
  net/mlx5e: Don't overwrite pedit action when multiple pedit used
  net/mlx5e: Update hw flows when encap source mac changed
  qed*: Advance drivers version to 8.37.0.20
  qed: Change verbosity for coalescing message.
  qede: Fix system crash on configuring channels.
  qed: Consider TX tcs while deriving the max num_queues for PF.
  ...
2019-02-08 11:21:54 -08:00
Miroslav Benes d325c40296 ring-buffer: Remove unused function ring_buffer_page_len()
Commit 6b7e633fe9 ("tracing: Remove extra zeroing out of the ring
buffer page") removed the only caller of ring_buffer_page_len(). The
function is now unused and may be removed.

Link: http://lkml.kernel.org/r/20181228133847.106177-1-mbenes@suse.cz

Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-06 11:58:33 -05:00
Changbin Du f52d569f3d tracing: Show stacktrace for wakeup tracers
This align the behavior of wakeup tracers with irqsoff latency tracer
that we record stacktrace at the beginning and end of waking up. The
stacktrace shows us what is happening in the kernel.

Link: http://lkml.kernel.org/r/20190116160249.7554-1-changbin.du@gmail.com

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-06 11:56:19 -05:00
Changbin Du afbab501c6 tracing: Put a margin between flags and duration for wakeup tracers
Don't mix context flags with function duration info.

Instead of this:

 # tracer: wakeup_rt
 #
 # wakeup_rt latency trace v1.1.5 on 5.0.0-rc1-test+
 # --------------------------------------------------------------------
 # latency: 177 us, #545/545, CPU#0 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:8)
 #    -----------------
 #    | task: migration/0-11 (uid:0 nice:0 policy:1 rt_prio:99)
 #    -----------------
 #
 #                                       _-----=> irqs-off
 #                                      / _----=> need-resched
 #                                     | / _---=> hardirq/softirq
 #                                     || / _--=> preempt-depth
 #                                     ||| /
 #   REL TIME      CPU  TASK/PID       ||||  DURATION                  FUNCTION CALLS
 #      |          |     |    |        ||||   |   |                     |   |   |   |
         0 us |   0)    <idle>-0    |  dNh5              |  /*      0:120:R   + [000]    11:  0:R migration/0 */
         2 us |   0)    <idle>-0    |  dNh5  0.000 us    |            (null)();
         4 us |   0)    <idle>-0    |  dNh4              |  _raw_spin_unlock() {
         4 us |   0)    <idle>-0    |  dNh4  0.304 us    |    preempt_count_sub();
         5 us |   0)    <idle>-0    |  dNh3  1.063 us    |  }
         5 us |   0)    <idle>-0    |  dNh3  0.266 us    |  ttwu_stat();
         6 us |   0)    <idle>-0    |  dNh3              |  _raw_spin_unlock_irqrestore() {
         6 us |   0)    <idle>-0    |  dNh3  0.273 us    |    preempt_count_sub();
         6 us |   0)    <idle>-0    |  dNh2  0.818 us    |  }

Show this:

 # tracer: wakeup
 #
 # wakeup latency trace v1.1.5 on 4.20.0+
 # --------------------------------------------------------------------
 # latency: 593 us, #674/674, CPU#0 | (M:desktop VP:0, KP:0, SP:0 HP:0 #P:4)
 #    -----------------
 #    | task: kworker/0:1H-339 (uid:0 nice:-20 policy:0 rt_prio:0)
 #    -----------------
 #
 #                                      _-----=> irqs-off
 #                                     / _----=> need-resched
 #                                    | / _---=> hardirq/softirq
 #                                    || / _--=> preempt-depth
 #                                    ||| /
 #  REL TIME      CPU  TASK/PID       ||||     DURATION                  FUNCTION CALLS
 #     |          |     |    |        ||||      |   |                     |   |   |   |
        0 us |   0)    <idle>-0    |  dNs. |               |  /*      0:120:R   + [000]   339💯R kworker/0:1H */
        3 us |   0)    <idle>-0    |  dNs. |   0.000 us    |            (null)();
       67 us |   0)    <idle>-0    |  dNs. |   0.721 us    |  ttwu_stat();
       69 us |   0)    <idle>-0    |  dNs. |   0.607 us    |  _raw_spin_unlock_irqrestore();
       71 us |   0)    <idle>-0    |  .Ns. |   0.598 us    |  _raw_spin_lock_irq();
       72 us |   0)    <idle>-0    |  .Ns. |   0.584 us    |  _raw_spin_lock_irq();
       73 us |   0)    <idle>-0    |  dNs. | + 11.118 us   |  __next_timer_interrupt();
       75 us |   0)    <idle>-0    |  dNs. |               |  call_timer_fn() {
       76 us |   0)    <idle>-0    |  dNs. |               |    delayed_work_timer_fn() {
       76 us |   0)    <idle>-0    |  dNs. |               |      __queue_work() {
       ...

Link: http://lkml.kernel.org/r/20190101154614.8887-4-changbin.du@gmail.com

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-06 11:56:19 -05:00
Changbin Du 97f0a3bcdf tracing: Show more info for funcgraph wakeup tracers
Add these info fields to funcgraph wakeup tracers:
  o Show CPU info since the waker could be on a different CPU.
  o Show function duration and overhead.
  o Show IRQ markers.

Link: http://lkml.kernel.org/r/20190101154614.8887-3-changbin.du@gmail.com

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-06 11:56:19 -05:00
Steven Rostedt (VMware) 6c6dbce196 tracing: Add comment to predicate_parse() about "&&" or "||"
As the predicat_parse() code is rather complex, commenting subtleties is
important. The switch case statement should be commented to describe that it
is only looking for two '&' or '|' together, which is why the fall through
to an error is after the check.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-06 11:56:19 -05:00
Mathieu Malaterre 9399ca21d2 tracing: Annotate implicit fall through in predicate_parse()
There is a plan to build the kernel with -Wimplicit-fallthrough and
this place in the code produced a warning (W=1).

This commit remove the following warning:

  kernel/trace/trace_events_filter.c:494:8: warning: this statement may fall through [-Wimplicit-fallthrough=]

Link: http://lkml.kernel.org/r/20190114203039.16535-2-malat@debian.org

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-06 11:56:18 -05:00
Mathieu Malaterre 91457c018f tracing: Annotate implicit fall through in parse_probe_arg()
There is a plan to build the kernel with -Wimplicit-fallthrough and
this place in the code produced a warning (W=1).

This commit remove the following warning:

  kernel/trace/trace_probe.c:302:6: warning: this statement may fall through [-Wimplicit-fallthrough=]

Link: http://lkml.kernel.org/r/20190114203039.16535-1-malat@debian.org

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-06 11:56:18 -05:00
Changbin Du 9acd8de69d function_graph: Support displaying relative timestamp
When function_graph is used for latency tracers, relative timestamp
is more straightforward than absolute timestamp as function trace
does. This change adds relative timestamp support to function_graph
and applies to latency tracers (wakeup and irqsoff).

Instead of:

 # tracer: irqsoff
 #
 # irqsoff latency trace v1.1.5 on 5.0.0-rc1-test
 # --------------------------------------------------------------------
 # latency: 521 us, #1125/1125, CPU#2 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:8)
 #    -----------------
 #    | task: swapper/2-0 (uid:0 nice:0 policy:0 rt_prio:0)
 #    -----------------
 #  => started at: __schedule
 #  => ended at:   _raw_spin_unlock_irq
 #
 #
 #                                       _-----=> irqs-off
 #                                      / _----=> need-resched
 #                                     | / _---=> hardirq/softirq
 #                                     || / _--=> preempt-depth
 #                                     ||| /
 #     TIME        CPU  TASK/PID       ||||  DURATION                  FUNCTION CALLS
 #      |          |     |    |        ||||   |   |                     |   |   |   |
   124.974306 |   2)  systemd-693   |  d..1  0.000 us    |  __schedule();
   124.974307 |   2)  systemd-693   |  d..1              |    rcu_note_context_switch() {
   124.974308 |   2)  systemd-693   |  d..1  0.487 us    |      rcu_preempt_deferred_qs();
   124.974309 |   2)  systemd-693   |  d..1  0.451 us    |      rcu_qs();
   124.974310 |   2)  systemd-693   |  d..1  2.301 us    |    }
[..]
   124.974826 |   2)    <idle>-0    |  d..2              |  finish_task_switch() {
   124.974826 |   2)    <idle>-0    |  d..2              |    _raw_spin_unlock_irq() {
   124.974827 |   2)    <idle>-0    |  d..2  0.000 us    |  _raw_spin_unlock_irq();
   124.974828 |   2)    <idle>-0    |  d..2  0.000 us    |  tracer_hardirqs_on();
   <idle>-0       2d..2  552us : <stack trace>
  => __schedule
  => schedule_idle
  => do_idle
  => cpu_startup_entry
  => start_secondary
  => secondary_startup_64

Show:

 # tracer: irqsoff
 #
 # irqsoff latency trace v1.1.5 on 5.0.0-rc1-test+
 # --------------------------------------------------------------------
 # latency: 511 us, #1053/1053, CPU#7 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:8)
 #    -----------------
 #    | task: swapper/7-0 (uid:0 nice:0 policy:0 rt_prio:0)
 #    -----------------
 #  => started at: __schedule
 #  => ended at:   _raw_spin_unlock_irq
 #
 #
 #                                       _-----=> irqs-off
 #                                      / _----=> need-resched
 #                                     | / _---=> hardirq/softirq
 #                                     || / _--=> preempt-depth
 #                                     ||| /
 #   REL TIME      CPU  TASK/PID       ||||  DURATION                  FUNCTION CALLS
 #      |          |     |    |        ||||   |   |                     |   |   |   |
         0 us |   7)   sshd-1704    |  d..1  0.000 us    |  __schedule();
         1 us |   7)   sshd-1704    |  d..1              |    rcu_note_context_switch() {
         1 us |   7)   sshd-1704    |  d..1  0.611 us    |      rcu_preempt_deferred_qs();
         2 us |   7)   sshd-1704    |  d..1  0.484 us    |      rcu_qs();
         3 us |   7)   sshd-1704    |  d..1  2.599 us    |    }
[..]
       509 us |   7)    <idle>-0    |  d..2              |  finish_task_switch() {
       510 us |   7)    <idle>-0    |  d..2              |    _raw_spin_unlock_irq() {
       510 us |   7)    <idle>-0    |  d..2  0.000 us    |  _raw_spin_unlock_irq();
       512 us |   7)    <idle>-0    |  d..2  0.000 us    |  tracer_hardirqs_on();
   <idle>-0       7d..2  543us : <stack trace>
  => __schedule
  => schedule_idle
  => do_idle
  => cpu_startup_entry
  => start_secondary
  => secondary_startup_64

Link: http://lkml.kernel.org/r/20190101154614.8887-2-changbin.du@gmail.com

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-06 11:56:18 -05:00
Jann Horn 01e7187b41 pipe: stop using ->can_merge
Al Viro pointed out that since there is only one pipe buffer type to which
new data can be appended, it isn't necessary to have a ->can_merge field in
struct pipe_buf_operations, we can just check for a magic type.

Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-02-01 02:01:45 -05:00
Alexei Starovoitov e16ec34039 bpf: fix potential deadlock in bpf_prog_register
Lockdep found a potential deadlock between cpu_hotplug_lock, bpf_event_mutex, and cpuctx_mutex:
[   13.007000] WARNING: possible circular locking dependency detected
[   13.007587] 5.0.0-rc3-00018-g2fa53f892422-dirty #477 Not tainted
[   13.008124] ------------------------------------------------------
[   13.008624] test_progs/246 is trying to acquire lock:
[   13.009030] 0000000094160d1d (tracepoints_mutex){+.+.}, at: tracepoint_probe_register_prio+0x2d/0x300
[   13.009770]
[   13.009770] but task is already holding lock:
[   13.010239] 00000000d663ef86 (bpf_event_mutex){+.+.}, at: bpf_probe_register+0x1d/0x60
[   13.010877]
[   13.010877] which lock already depends on the new lock.
[   13.010877]
[   13.011532]
[   13.011532] the existing dependency chain (in reverse order) is:
[   13.012129]
[   13.012129] -> #4 (bpf_event_mutex){+.+.}:
[   13.012582]        perf_event_query_prog_array+0x9b/0x130
[   13.013016]        _perf_ioctl+0x3aa/0x830
[   13.013354]        perf_ioctl+0x2e/0x50
[   13.013668]        do_vfs_ioctl+0x8f/0x6a0
[   13.014003]        ksys_ioctl+0x70/0x80
[   13.014320]        __x64_sys_ioctl+0x16/0x20
[   13.014668]        do_syscall_64+0x4a/0x180
[   13.015007]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   13.015469]
[   13.015469] -> #3 (&cpuctx_mutex){+.+.}:
[   13.015910]        perf_event_init_cpu+0x5a/0x90
[   13.016291]        perf_event_init+0x1b2/0x1de
[   13.016654]        start_kernel+0x2b8/0x42a
[   13.016995]        secondary_startup_64+0xa4/0xb0
[   13.017382]
[   13.017382] -> #2 (pmus_lock){+.+.}:
[   13.017794]        perf_event_init_cpu+0x21/0x90
[   13.018172]        cpuhp_invoke_callback+0xb3/0x960
[   13.018573]        _cpu_up+0xa7/0x140
[   13.018871]        do_cpu_up+0xa4/0xc0
[   13.019178]        smp_init+0xcd/0xd2
[   13.019483]        kernel_init_freeable+0x123/0x24f
[   13.019878]        kernel_init+0xa/0x110
[   13.020201]        ret_from_fork+0x24/0x30
[   13.020541]
[   13.020541] -> #1 (cpu_hotplug_lock.rw_sem){++++}:
[   13.021051]        static_key_slow_inc+0xe/0x20
[   13.021424]        tracepoint_probe_register_prio+0x28c/0x300
[   13.021891]        perf_trace_event_init+0x11f/0x250
[   13.022297]        perf_trace_init+0x6b/0xa0
[   13.022644]        perf_tp_event_init+0x25/0x40
[   13.023011]        perf_try_init_event+0x6b/0x90
[   13.023386]        perf_event_alloc+0x9a8/0xc40
[   13.023754]        __do_sys_perf_event_open+0x1dd/0xd30
[   13.024173]        do_syscall_64+0x4a/0x180
[   13.024519]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   13.024968]
[   13.024968] -> #0 (tracepoints_mutex){+.+.}:
[   13.025434]        __mutex_lock+0x86/0x970
[   13.025764]        tracepoint_probe_register_prio+0x2d/0x300
[   13.026215]        bpf_probe_register+0x40/0x60
[   13.026584]        bpf_raw_tracepoint_open.isra.34+0xa4/0x130
[   13.027042]        __do_sys_bpf+0x94f/0x1a90
[   13.027389]        do_syscall_64+0x4a/0x180
[   13.027727]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   13.028171]
[   13.028171] other info that might help us debug this:
[   13.028171]
[   13.028807] Chain exists of:
[   13.028807]   tracepoints_mutex --> &cpuctx_mutex --> bpf_event_mutex
[   13.028807]
[   13.029666]  Possible unsafe locking scenario:
[   13.029666]
[   13.030140]        CPU0                    CPU1
[   13.030510]        ----                    ----
[   13.030875]   lock(bpf_event_mutex);
[   13.031166]                                lock(&cpuctx_mutex);
[   13.031645]                                lock(bpf_event_mutex);
[   13.032135]   lock(tracepoints_mutex);
[   13.032441]
[   13.032441]  *** DEADLOCK ***
[   13.032441]
[   13.032911] 1 lock held by test_progs/246:
[   13.033239]  #0: 00000000d663ef86 (bpf_event_mutex){+.+.}, at: bpf_probe_register+0x1d/0x60
[   13.033909]
[   13.033909] stack backtrace:
[   13.034258] CPU: 1 PID: 246 Comm: test_progs Not tainted 5.0.0-rc3-00018-g2fa53f892422-dirty #477
[   13.034964] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014
[   13.035657] Call Trace:
[   13.035859]  dump_stack+0x5f/0x8b
[   13.036130]  print_circular_bug.isra.37+0x1ce/0x1db
[   13.036526]  __lock_acquire+0x1158/0x1350
[   13.036852]  ? lock_acquire+0x98/0x190
[   13.037154]  lock_acquire+0x98/0x190
[   13.037447]  ? tracepoint_probe_register_prio+0x2d/0x300
[   13.037876]  __mutex_lock+0x86/0x970
[   13.038167]  ? tracepoint_probe_register_prio+0x2d/0x300
[   13.038600]  ? tracepoint_probe_register_prio+0x2d/0x300
[   13.039028]  ? __mutex_lock+0x86/0x970
[   13.039337]  ? __mutex_lock+0x24a/0x970
[   13.039649]  ? bpf_probe_register+0x1d/0x60
[   13.039992]  ? __bpf_trace_sched_wake_idle_without_ipi+0x10/0x10
[   13.040478]  ? tracepoint_probe_register_prio+0x2d/0x300
[   13.040906]  tracepoint_probe_register_prio+0x2d/0x300
[   13.041325]  bpf_probe_register+0x40/0x60
[   13.041649]  bpf_raw_tracepoint_open.isra.34+0xa4/0x130
[   13.042068]  ? __might_fault+0x3e/0x90
[   13.042374]  __do_sys_bpf+0x94f/0x1a90
[   13.042678]  do_syscall_64+0x4a/0x180
[   13.042975]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   13.043382] RIP: 0033:0x7f23b10a07f9
[   13.045155] RSP: 002b:00007ffdef42fdd8 EFLAGS: 00000202 ORIG_RAX: 0000000000000141
[   13.045759] RAX: ffffffffffffffda RBX: 00007ffdef42ff70 RCX: 00007f23b10a07f9
[   13.046326] RDX: 0000000000000070 RSI: 00007ffdef42fe10 RDI: 0000000000000011
[   13.046893] RBP: 00007ffdef42fdf0 R08: 0000000000000038 R09: 00007ffdef42fe10
[   13.047462] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
[   13.048029] R13: 0000000000000016 R14: 00007f23b1db4690 R15: 0000000000000000

Since tracepoints_mutex will be taken in tracepoint_probe_register/unregister()
there is no need to take bpf_event_mutex too.
bpf_event_mutex is protecting modifications to prog array used in kprobe/perf bpf progs.
bpf_raw_tracepoints don't need to take this mutex.

Fixes: c4f6699dfc ("bpf: introduce BPF_RAW_TRACEPOINT")
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-01-31 23:18:21 +01:00
Arnaldo Carvalho de Melo 5620196951 perf: Make perf_event_output() propagate the output() return
For the original mode of operation it isn't needed, since we report back
errors via PERF_RECORD_LOST records in the ring buffer, but for use in
bpf_perf_event_output() it is convenient to return the errors, basically
-ENOSPC.

Currently bpf_perf_event_output() returns an error indication, the last
thing it does, which is to push it to the ring buffer is that can fail
and if so, this failure won't be reported back to its users, fix it.

Reported-by: Jamal Hadi Salim <jhs@mojatatu.com>
Tested-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/r/20190118150938.GN5823@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-01-21 17:00:57 -03:00
Andreas Ziegler 0722069a53 tracing/uprobes: Fix output for multiple string arguments
When printing multiple uprobe arguments as strings the output for the
earlier arguments would also include all later string arguments.

This is best explained in an example:

Consider adding a uprobe to a function receiving two strings as
parameters which is at offset 0xa0 in strlib.so and we want to print
both parameters when the uprobe is hit (on x86_64):

$ echo 'p:func /lib/strlib.so:0xa0 +0(%di):string +0(%si):string' > \
    /sys/kernel/debug/tracing/uprobe_events

When the function is called as func("foo", "bar") and we hit the probe,
the trace file shows a line like the following:

  [...] func: (0x7f7e683706a0) arg1="foobar" arg2="bar"

Note the extra "bar" printed as part of arg1. This behaviour stacks up
for additional string arguments.

The strings are stored in a dynamically growing part of the uprobe
buffer by fetch_store_string() after copying them from userspace via
strncpy_from_user(). The return value of strncpy_from_user() is then
directly used as the required size for the string. However, this does
not take the terminating null byte into account as the documentation
for strncpy_from_user() cleary states that it "[...] returns the
length of the string (not including the trailing NUL)" even though the
null byte will be copied to the destination.

Therefore, subsequent calls to fetch_store_string() will overwrite
the terminating null byte of the most recently fetched string with
the first character of the current string, leading to the
"accumulation" of strings in earlier arguments in the output.

Fix this by incrementing the return value of strncpy_from_user() by
one if we did not hit the maximum buffer size.

Link: http://lkml.kernel.org/r/20190116141629.5752-1-andreas.ziegler@fau.de

Cc: Ingo Molnar <mingo@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 5baaa59ef0 ("tracing/probes: Implement 'memory' fetch method for uprobes")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Andreas Ziegler <andreas.ziegler@fau.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-01-17 10:54:08 -05:00
Andreas Ziegler ea6eb5e7d1 tracing: uprobes: Fix typo in pr_fmt string
The subsystem-specific message prefix for uprobes was also
"trace_kprobe: " instead of "trace_uprobe: " as described in
the original commit message.

Link: http://lkml.kernel.org/r/20190117133023.19292-1-andreas.ziegler@fau.de

Cc: Ingo Molnar <mingo@redhat.com>
Cc: stable@vger.kernel.org
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: 7257634135 ("tracing/probe: Show subsystem name in messages")
Signed-off-by: Andreas Ziegler <andreas.ziegler@fau.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-01-17 09:51:42 -05:00
Andrea Righi 8b05a3a750 tracing/kprobes: Fix NULL pointer dereference in trace_kprobe_create()
It is possible to trigger a NULL pointer dereference by writing an
incorrectly formatted string to krpobe_events (trying to create a
kretprobe omitting the symbol).

Example:

 echo "r:event_1 " >> /sys/kernel/debug/tracing/kprobe_events

That triggers this:

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
 #PF error: [normal kernel read fault]
 PGD 0 P4D 0
 Oops: 0000 [#1] SMP PTI
 CPU: 6 PID: 1757 Comm: bash Not tainted 5.0.0-rc1+ #125
 Hardware name: Dell Inc. XPS 13 9370/0F6P3V, BIOS 1.5.1 08/09/2018
 RIP: 0010:kstrtoull+0x2/0x20
 Code: 28 00 00 00 75 17 48 83 c4 18 5b 41 5c 5d c3 b8 ea ff ff ff eb e1 b8 de ff ff ff eb da e8 d6 36 bb ff 66 0f 1f 44 00 00 31 c0 <80> 3f 2b 55 48 89 e5 0f 94 c0 48 01 c7 e8 5c ff ff ff 5d c3 66 2e
 RSP: 0018:ffffb5d482e57cb8 EFLAGS: 00010246
 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff82b12720
 RDX: ffffb5d482e57cf8 RSI: 0000000000000000 RDI: 0000000000000000
 RBP: ffffb5d482e57d70 R08: ffffa0c05e5a7080 R09: ffffa0c05e003980
 R10: 0000000000000000 R11: 0000000040000000 R12: ffffa0c04fe87b08
 R13: 0000000000000001 R14: 000000000000000b R15: ffffa0c058d749e1
 FS:  00007f137c7f7740(0000) GS:ffffa0c05e580000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000000 CR3: 0000000497d46004 CR4: 00000000003606e0
 Call Trace:
  ? trace_kprobe_create+0xb6/0x840
  ? _cond_resched+0x19/0x40
  ? _cond_resched+0x19/0x40
  ? __kmalloc+0x62/0x210
  ? argv_split+0x8f/0x140
  ? trace_kprobe_create+0x840/0x840
  ? trace_kprobe_create+0x840/0x840
  create_or_delete_trace_kprobe+0x11/0x30
  trace_run_command+0x50/0x90
  trace_parse_run_command+0xc1/0x160
  probes_write+0x10/0x20
  __vfs_write+0x3a/0x1b0
  ? apparmor_file_permission+0x1a/0x20
  ? security_file_permission+0x31/0xf0
  ? _cond_resched+0x19/0x40
  vfs_write+0xb1/0x1a0
  ksys_write+0x55/0xc0
  __x64_sys_write+0x1a/0x20
  do_syscall_64+0x5a/0x120
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fix by doing the proper argument checks in trace_kprobe_create().

Cc: Ingo Molnar <mingo@redhat.com>
Link: https://lore.kernel.org/lkml/20190111095108.b79a2ee026185cbd62365977@kernel.org
Link: http://lkml.kernel.org/r/20190111060113.GA22841@xps-13
Fixes: 6212dd2968 ("tracing/kprobes: Use dyn_event framework for kprobe events")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Andrea Righi <righi.andrea@gmail.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-01-15 11:33:45 -05:00
Linus Torvalds 96d4f267e4 Remove 'type' argument from access_ok() function
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.

It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access.  But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.

A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model.  And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.

This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.

There were a couple of notable cases:

 - csky still had the old "verify_area()" name as an alias.

 - the iter_iov code had magical hardcoded knowledge of the actual
   values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
   really used it)

 - microblaze used the type argument for a debug printout

but other than those oddities this should be a total no-op patch.

I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something.  Any missed conversion should be trivially fixable, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-03 18:57:57 -08:00
Linus Torvalds 495d714ad1 Tracing changes for v4.21:
- Rework of the kprobe/uprobe and synthetic events to consolidate all
    the dynamic event code. This will make changes in the future easier.
 
  - Partial rewrite of the function graph tracing infrastructure.
    This will allow for multiple users of hooking onto functions
    to get the callback (return) of the function. This is the ground
    work for having kprobes and function graph tracer using one code base.
 
  - Clean up of the histogram code that will facilitate adding more
    features to the histograms in the future.
 
  - Addition of str_has_prefix() and a few use cases. There currently
    is a similar function strstart() that is used in a few places, but
    only returns a bool and not a length. These instances will be
    removed in the future to use str_has_prefix() instead.
 
  - A few other various clean ups as well.
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Merge tag 'trace-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:

 - Rework of the kprobe/uprobe and synthetic events to consolidate all
   the dynamic event code. This will make changes in the future easier.

 - Partial rewrite of the function graph tracing infrastructure. This
   will allow for multiple users of hooking onto functions to get the
   callback (return) of the function. This is the ground work for having
   kprobes and function graph tracer using one code base.

 - Clean up of the histogram code that will facilitate adding more
   features to the histograms in the future.

 - Addition of str_has_prefix() and a few use cases. There currently is
   a similar function strstart() that is used in a few places, but only
   returns a bool and not a length. These instances will be removed in
   the future to use str_has_prefix() instead.

 - A few other various clean ups as well.

* tag 'trace-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (57 commits)
  tracing: Use the return of str_has_prefix() to remove open coded numbers
  tracing: Have the historgram use the result of str_has_prefix() for len of prefix
  tracing: Use str_has_prefix() instead of using fixed sizes
  tracing: Use str_has_prefix() helper for histogram code
  string.h: Add str_has_prefix() helper function
  tracing: Make function ‘ftrace_exports’ static
  tracing: Simplify printf'ing in seq_print_sym
  tracing: Avoid -Wformat-nonliteral warning
  tracing: Merge seq_print_sym_short() and seq_print_sym_offset()
  tracing: Add hist trigger comments for variable-related fields
  tracing: Remove hist trigger synth_var_refs
  tracing: Use hist trigger's var_ref array to destroy var_refs
  tracing: Remove open-coding of hist trigger var_ref management
  tracing: Use var_refs[] for hist trigger reference checking
  tracing: Change strlen to sizeof for hist trigger static strings
  tracing: Remove unnecessary hist trigger struct field
  tracing: Fix ftrace_graph_get_ret_stack() to use task and not current
  seq_buf: Use size_t for len in seq_buf_puts()
  seq_buf: Make seq_buf_puts() null-terminate the buffer
  arm64: Use ftrace_graph_get_ret_stack() instead of curr_ret_stack
  ...
2018-12-31 11:46:59 -08:00
Linus Torvalds 0e9da3fbf7 for-4.21/block-20181221
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Merge tag 'for-4.21/block-20181221' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
 "This is the main pull request for block/storage for 4.21.

  Larger than usual, it was a busy round with lots of goodies queued up.
  Most notable is the removal of the old IO stack, which has been a long
  time coming. No new features for a while, everything coming in this
  week has all been fixes for things that were previously merged.

  This contains:

   - Use atomic counters instead of semaphores for mtip32xx (Arnd)

   - Cleanup of the mtip32xx request setup (Christoph)

   - Fix for circular locking dependency in loop (Jan, Tetsuo)

   - bcache (Coly, Guoju, Shenghui)
      * Optimizations for writeback caching
      * Various fixes and improvements

   - nvme (Chaitanya, Christoph, Sagi, Jay, me, Keith)
      * host and target support for NVMe over TCP
      * Error log page support
      * Support for separate read/write/poll queues
      * Much improved polling
      * discard OOM fallback
      * Tracepoint improvements

   - lightnvm (Hans, Hua, Igor, Matias, Javier)
      * Igor added packed metadata to pblk. Now drives without metadata
        per LBA can be used as well.
      * Fix from Geert on uninitialized value on chunk metadata reads.
      * Fixes from Hans and Javier to pblk recovery and write path.
      * Fix from Hua Su to fix a race condition in the pblk recovery
        code.
      * Scan optimization added to pblk recovery from Zhoujie.
      * Small geometry cleanup from me.

   - Conversion of the last few drivers that used the legacy path to
     blk-mq (me)

   - Removal of legacy IO path in SCSI (me, Christoph)

   - Removal of legacy IO stack and schedulers (me)

   - Support for much better polling, now without interrupts at all.
     blk-mq adds support for multiple queue maps, which enables us to
     have a map per type. This in turn enables nvme to have separate
     completion queues for polling, which can then be interrupt-less.
     Also means we're ready for async polled IO, which is hopefully
     coming in the next release.

   - Killing of (now) unused block exports (Christoph)

   - Unification of the blk-rq-qos and blk-wbt wait handling (Josef)

   - Support for zoned testing with null_blk (Masato)

   - sx8 conversion to per-host tag sets (Christoph)

   - IO priority improvements (Damien)

   - mq-deadline zoned fix (Damien)

   - Ref count blkcg series (Dennis)

   - Lots of blk-mq improvements and speedups (me)

   - sbitmap scalability improvements (me)

   - Make core inflight IO accounting per-cpu (Mikulas)

   - Export timeout setting in sysfs (Weiping)

   - Cleanup the direct issue path (Jianchao)

   - Export blk-wbt internals in block debugfs for easier debugging
     (Ming)

   - Lots of other fixes and improvements"

* tag 'for-4.21/block-20181221' of git://git.kernel.dk/linux-block: (364 commits)
  kyber: use sbitmap add_wait_queue/list_del wait helpers
  sbitmap: add helpers for add/del wait queue handling
  block: save irq state in blkg_lookup_create()
  dm: don't reuse bio for flushes
  nvme-pci: trace SQ status on completions
  nvme-rdma: implement polling queue map
  nvme-fabrics: allow user to pass in nr_poll_queues
  nvme-fabrics: allow nvmf_connect_io_queue to poll
  nvme-core: optionally poll sync commands
  block: make request_to_qc_t public
  nvme-tcp: fix spelling mistake "attepmpt" -> "attempt"
  nvme-tcp: fix endianess annotations
  nvmet-tcp: fix endianess annotations
  nvme-pci: refactor nvme_poll_irqdisable to make sparse happy
  nvme-pci: only set nr_maps to 2 if poll queues are supported
  nvmet: use a macro for default error location
  nvmet: fix comparison of a u16 with -1
  blk-mq: enable IO poll if .nr_queues of type poll > 0
  blk-mq: change blk_mq_queue_busy() to blk_mq_queue_inflight()
  blk-mq: skip zero-queue maps in blk_mq_map_swqueue
  ...
2018-12-28 13:19:59 -08:00
Linus Torvalds e0c38a4d1f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) New ipset extensions for matching on destination MAC addresses, from
    Stefano Brivio.

 2) Add ipv4 ttl and tos, plus ipv6 flow label and hop limit offloads to
    nfp driver. From Stefano Brivio.

 3) Implement GRO for plain UDP sockets, from Paolo Abeni.

 4) Lots of work from Michał Mirosław to eliminate the VLAN_TAG_PRESENT
    bit so that we could support the entire vlan_tci value.

 5) Rework the IPSEC policy lookups to better optimize more usecases,
    from Florian Westphal.

 6) Infrastructure changes eliminating direct manipulation of SKB lists
    wherever possible, and to always use the appropriate SKB list
    helpers. This work is still ongoing...

 7) Lots of PHY driver and state machine improvements and
    simplifications, from Heiner Kallweit.

 8) Various TSO deferral refinements, from Eric Dumazet.

 9) Add ntuple filter support to aquantia driver, from Dmitry Bogdanov.

10) Batch dropping of XDP packets in tuntap, from Jason Wang.

11) Lots of cleanups and improvements to the r8169 driver from Heiner
    Kallweit, including support for ->xmit_more. This driver has been
    getting some much needed love since he started working on it.

12) Lots of new forwarding selftests from Petr Machata.

13) Enable VXLAN learning in mlxsw driver, from Ido Schimmel.

14) Packed ring support for virtio, from Tiwei Bie.

15) Add new Aquantia AQtion USB driver, from Dmitry Bezrukov.

16) Add XDP support to dpaa2-eth driver, from Ioana Ciocoi Radulescu.

17) Implement coalescing on TCP backlog queue, from Eric Dumazet.

18) Implement carrier change in tun driver, from Nicolas Dichtel.

19) Support msg_zerocopy in UDP, from Willem de Bruijn.

20) Significantly improve garbage collection of neighbor objects when
    the table has many PERMANENT entries, from David Ahern.

21) Remove egdev usage from nfp and mlx5, and remove the facility
    completely from the tree as it no longer has any users. From Oz
    Shlomo and others.

22) Add a NETDEV_PRE_CHANGEADDR so that drivers can veto the change and
    therefore abort the operation before the commit phase (which is the
    NETDEV_CHANGEADDR event). From Petr Machata.

23) Add indirect call wrappers to avoid retpoline overhead, and use them
    in the GRO code paths. From Paolo Abeni.

24) Add support for netlink FDB get operations, from Roopa Prabhu.

25) Support bloom filter in mlxsw driver, from Nir Dotan.

26) Add SKB extension infrastructure. This consolidates the handling of
    the auxiliary SKB data used by IPSEC and bridge netfilter, and is
    designed to support the needs to MPTCP which could be integrated in
    the future.

27) Lots of XDP TX optimizations in mlx5 from Tariq Toukan.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1845 commits)
  net: dccp: fix kernel crash on module load
  drivers/net: appletalk/cops: remove redundant if statement and mask
  bnx2x: Fix NULL pointer dereference in bnx2x_del_all_vlans() on some hw
  net/net_namespace: Check the return value of register_pernet_subsys()
  net/netlink_compat: Fix a missing check of nla_parse_nested
  ieee802154: lowpan_header_create check must check daddr
  net/mlx4_core: drop useless LIST_HEAD
  mlxsw: spectrum: drop useless LIST_HEAD
  net/mlx5e: drop useless LIST_HEAD
  iptunnel: Set tun_flags in the iptunnel_metadata_reply from src
  net/mlx5e: fix semicolon.cocci warnings
  staging: octeon: fix build failure with XFRM enabled
  net: Revert recent Spectre-v1 patches.
  can: af_can: Fix Spectre v1 vulnerability
  packet: validate address length if non-zero
  nfc: af_nfc: Fix Spectre v1 vulnerability
  phonet: af_phonet: Fix Spectre v1 vulnerability
  net: core: Fix Spectre v1 vulnerability
  net: minor cleanup in skb_ext_add()
  net: drop the unused helper skb_ext_get()
  ...
2018-12-27 13:04:52 -08:00
Linus Torvalds 792bf4d871 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The biggest RCU changes in this cycle were:

   - Convert RCU's BUG_ON() and similar calls to WARN_ON() and similar.

   - Replace calls of RCU-bh and RCU-sched update-side functions to
     their vanilla RCU counterparts. This series is a step towards
     complete removal of the RCU-bh and RCU-sched update-side functions.

     ( Note that some of these conversions are going upstream via their
       respective maintainers. )

   - Documentation updates, including a number of flavor-consolidation
     updates from Joel Fernandes.

   - Miscellaneous fixes.

   - Automate generation of the initrd filesystem used for rcutorture
     testing.

   - Convert spin_is_locked() assertions to instead use lockdep.

     ( Note that some of these conversions are going upstream via their
       respective maintainers. )

   - SRCU updates, especially including a fix from Dennis Krein for a
     bag-on-head-class bug.

   - RCU torture-test updates"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (112 commits)
  rcutorture: Don't do busted forward-progress testing
  rcutorture: Use 100ms buckets for forward-progress callback histograms
  rcutorture: Recover from OOM during forward-progress tests
  rcutorture: Print forward-progress test age upon failure
  rcutorture: Print time since GP end upon forward-progress failure
  rcutorture: Print histogram of CB invocation at OOM time
  rcutorture: Print GP age upon forward-progress failure
  rcu: Print per-CPU callback counts for forward-progress failures
  rcu: Account for nocb-CPU callback counts in RCU CPU stall warnings
  rcutorture: Dump grace-period diagnostics upon forward-progress OOM
  rcutorture: Prepare for asynchronous access to rcu_fwd_startat
  torture: Remove unnecessary "ret" variables
  rcutorture: Affinity forward-progress test to avoid housekeeping CPUs
  rcutorture: Break up too-long rcu_torture_fwd_prog() function
  rcutorture: Remove cbflood facility
  torture: Bring any extra CPUs online during kernel startup
  rcutorture: Add call_rcu() flooding forward-progress tests
  rcutorture/formal: Replace synchronize_sched() with synchronize_rcu()
  tools/kernel.h: Replace synchronize_sched() with synchronize_rcu()
  net/decnet: Replace rcu_barrier_bh() with rcu_barrier()
  ...
2018-12-26 13:07:19 -08:00
Steven Rostedt (VMware) 3d739c1f61 tracing: Use the return of str_has_prefix() to remove open coded numbers
There are several locations that compare constants to the beginning of
string variables to determine what commands should be done, then the
constant length is used to index into the string. This is error prone as the
hard coded numbers have to match the size of the constants. Instead, use the
len returned from str_has_prefix() and remove the open coded string length
sizes.

Cc: Joe Perches <joe@perches.com>
Acked-by: Masami  Hiramatsu <mhiramat@kernel.org> (for trace_probe part)
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-22 22:52:30 -05:00
Steven Rostedt (VMware) 036876fa56 tracing: Have the historgram use the result of str_has_prefix() for len of prefix
As str_has_prefix() returns the length on match, we can use that for the
updating of the string pointer instead of recalculating the prefix size.

Cc: Tom Zanussi  <zanussi@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-22 22:52:09 -05:00
Steven Rostedt (VMware) b6b2735514 tracing: Use str_has_prefix() instead of using fixed sizes
There are several instances of strncmp(str, "const", 123), where 123 is the
strlen of the const string to check if "const" is the prefix of str. But
this can be error prone. Use str_has_prefix() instead.

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-22 22:51:54 -05:00
Steven Rostedt (VMware) 754481e695 tracing: Use str_has_prefix() helper for histogram code
The tracing histogram code contains a lot of instances of the construct:

 strncmp(str, "const", sizeof("const") - 1)

This can be prone to bugs due to typos or bad cut and paste. Use the
str_has_prefix() helper macro instead that removes the need for having two
copies of the constant string.

Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-22 22:51:01 -05:00
Mathieu Malaterre 1cce377df1 tracing: Make function ‘ftrace_exports’ static
In commit 478409dd68 ("tracing: Add hook to function tracing for other
subsystems to use"), a new function ‘ftrace_exports’ was added. Since
this function can be made static, make it so.

Silence the following warning triggered using W=1:

  kernel/trace/trace.c:2451:6: warning: no previous prototype for ‘ftrace_exports’ [-Wmissing-prototypes]

Link: http://lkml.kernel.org/r/20180516193012.25390-1-malat@debian.org

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-22 08:21:06 -05:00
Rasmus Villemoes bea6957d5c tracing: Simplify printf'ing in seq_print_sym
trace_seq_printf(..., "%s", ...) can be done with trace_seq_puts()
instead, avoiding printf overhead. In the second instance, the string
we're copying was just created from an snprintf() to a stack buffer, so
we might as well do that printf directly. This naturally leads to moving
the declaration of the str buffer inside the CONFIG_KALLSYMS guard,
which in turn will make gcc inline the function for !CONFIG_KALLSYMS (it
only has a single caller, but the huge stack frame seems to make gcc not
inline it for CONFIG_KALLSYMS).

Link: http://lkml.kernel.org/r/20181029223542.26175-4-linux@rasmusvillemoes.dk

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-22 08:21:06 -05:00
Rasmus Villemoes cc9f59fb3b tracing: Avoid -Wformat-nonliteral warning
Building with -Wformat-nonliteral, gcc complains

kernel/trace/trace_output.c: In function ‘seq_print_sym’:
kernel/trace/trace_output.c:356:3: warning: format not a string literal, argument types not checked [-Wformat-nonliteral]
   trace_seq_printf(s, fmt, name);

But seq_print_sym only has a single caller which passes "%s" as fmt, so
we might as well just use that directly. That also paves the way for
further cleanups that will actually make that format string go away
entirely.

Link: http://lkml.kernel.org/r/20181029223542.26175-3-linux@rasmusvillemoes.dk

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-22 08:21:06 -05:00
Rasmus Villemoes 59dd974bc0 tracing: Merge seq_print_sym_short() and seq_print_sym_offset()
These two functions are nearly identical, so we can avoid some code
duplication by moving the conditional into a common implementation.

Link: http://lkml.kernel.org/r/20181029223542.26175-2-linux@rasmusvillemoes.dk

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-22 08:21:05 -05:00
Tom Zanussi 05ddb25cb3 tracing: Add hist trigger comments for variable-related fields
Add a few comments to help clarify how variable and variable reference
fields are used in the code.

Link: http://lkml.kernel.org/r/ea857ce948531d7bec712bbb0f38360aa1d378ec.1545161087.git.tom.zanussi@linux.intel.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-22 08:21:05 -05:00
Tom Zanussi 912201345f tracing: Remove hist trigger synth_var_refs
All var_refs are now handled uniformly and there's no reason to treat
the synth_refs in a special way now, so remove them and associated
functions.

Link: http://lkml.kernel.org/r/b4d3470526b8f0426dcec125399dad9ad9b8589d.1545161087.git.tom.zanussi@linux.intel.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-22 08:21:05 -05:00
Tom Zanussi 656fe2ba85 tracing: Use hist trigger's var_ref array to destroy var_refs
Since every var ref for a trigger has an entry in the var_ref[] array,
use that to destroy the var_refs, instead of piecemeal via the field
expressions.

This allows us to avoid having to keep and treat differently separate
lists for the action-related references, which future patches will
remove.

Link: http://lkml.kernel.org/r/fad1a164f0e257c158e70d6eadbf6c586e04b2a2.1545161087.git.tom.zanussi@linux.intel.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-22 08:21:05 -05:00
Tom Zanussi de40f033d4 tracing: Remove open-coding of hist trigger var_ref management
Have create_var_ref() manage the hist trigger's var_ref list, rather
than having similar code doing it in multiple places.  This cleans up
the code and makes sure var_refs are always accounted properly.

Also, document the var_ref-related functions to make what their
purpose clearer.

Link: http://lkml.kernel.org/r/05ddae93ff514e66fc03897d6665231892939913.1545161087.git.tom.zanussi@linux.intel.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-22 08:21:04 -05:00
Tom Zanussi e4f6d24503 tracing: Use var_refs[] for hist trigger reference checking
Since all the variable reference hist_fields are collected into
hist_data->var_refs[] array, there's no need to go through all the
fields looking for them, or in separate arrays like synth_var_refs[],
which will be going away soon anyway.

This also allows us to get rid of some unnecessary code and functions
currently used for the same purpose.

Link: http://lkml.kernel.org/r/1545246556.4239.7.camel@gmail.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-22 08:21:04 -05:00
Tom Zanussi 2f31ed9308 tracing: Change strlen to sizeof for hist trigger static strings
There's no need to use strlen() for static strings when the length is
already known, so update trace_events_hist.c with sizeof() for those
cases.

Link: http://lkml.kernel.org/r/e3e754f2bd18e56eaa8baf79bee619316ebf4cfc.1545161087.git.tom.zanussi@linux.intel.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-22 08:21:04 -05:00
Tom Zanussi 6801f0d5ca tracing: Remove unnecessary hist trigger struct field
hist_field.var_idx is completely unused, so remove it.

Link: http://lkml.kernel.org/r/d4e066c0f509f5f13ad3babc8c33ca6e7ddc439a.1545161087.git.tom.zanussi@linux.intel.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-22 08:21:03 -05:00
Steven Rostedt (VMware) e8d086ddb5 tracing: Fix ftrace_graph_get_ret_stack() to use task and not current
The function ftrace_graph_get_ret_stack() takes a task struct descriptor but
uses current as the task to perform the operations on. In pretty much all
cases the task decriptor is the same as current, so this wasn't an issue.
But there is a case in the ARM architecture that passes in a task that is
not current, and expects a result from that task, and this code breaks it.

Fixes: 51584396cff5 ("arm64: Use ftrace_graph_get_ret_stack() instead of curr_ret_stack")
Reported-by: James Morse <james.morse@arm.com>
Tested-by: James Morse <james.morse@arm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-22 08:21:03 -05:00
David S. Miller 339bbff2d6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2018-12-21

The following pull-request contains BPF updates for your *net-next* tree.

There is a merge conflict in test_verifier.c. Result looks as follows:

        [...]
        },
        {
                "calls: cross frame pruning",
                .insns = {
                [...]
                .prog_type = BPF_PROG_TYPE_SOCKET_FILTER,
                .errstr_unpriv = "function calls to other bpf functions are allowed for root only",
                .result_unpriv = REJECT,
                .errstr = "!read_ok",
                .result = REJECT,
	},
        {
                "jset: functional",
                .insns = {
        [...]
        {
                "jset: unknown const compare not taken",
                .insns = {
                        BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
                                     BPF_FUNC_get_prandom_u32),
                        BPF_JMP_IMM(BPF_JSET, BPF_REG_0, 1, 1),
                        BPF_LDX_MEM(BPF_B, BPF_REG_8, BPF_REG_9, 0),
                        BPF_EXIT_INSN(),
                },
                .prog_type = BPF_PROG_TYPE_SOCKET_FILTER,
                .errstr_unpriv = "!read_ok",
                .result_unpriv = REJECT,
                .errstr = "!read_ok",
                .result = REJECT,
        },
        [...]
        {
                "jset: range",
                .insns = {
                [...]
                },
                .prog_type = BPF_PROG_TYPE_SOCKET_FILTER,
                .result_unpriv = ACCEPT,
                .result = ACCEPT,
        },

The main changes are:

1) Various BTF related improvements in order to get line info
   working. Meaning, verifier will now annotate the corresponding
   BPF C code to the error log, from Martin and Yonghong.

2) Implement support for raw BPF tracepoints in modules, from Matt.

3) Add several improvements to verifier state logic, namely speeding
   up stacksafe check, optimizations for stack state equivalence
   test and safety checks for liveness analysis, from Alexei.

4) Teach verifier to make use of BPF_JSET instruction, add several
   test cases to kselftests and remove nfp specific JSET optimization
   now that verifier has awareness, from Jakub.

5) Improve BPF verifier's slot_type marking logic in order to
   allow more stack slot sharing, from Jiong.

6) Add sk_msg->size member for context access and add set of fixes
   and improvements to make sock_map with kTLS usable with openssl
   based applications, from John.

7) Several cleanups and documentation updates in bpftool as well as
   auto-mount of tracefs for "bpftool prog tracelog" command,
   from Quentin.

8) Include sub-program tags from now on in bpf_prog_info in order to
   have a reliable way for user space to get all tags of the program
   e.g. needed for kallsyms correlation, from Song.

9) Add BTF annotations for cgroup_local_storage BPF maps and
   implement bpf fs pretty print support, from Roman.

10) Fix bpftool in order to allow for cross-compilation, from Ivan.

11) Update of bpftool license to GPLv2-only + BSD-2-Clause in order
    to be compatible with libbfd and allow for Debian packaging,
    from Jakub.

12) Remove an obsolete prog->aux sanitation in dump and get rid of
    version check for prog load, from Daniel.

13) Fix a memory leak in libbpf's line info handling, from Prashant.

14) Fix cpumap's frame alignment for build_skb() so that skb_shared_info
    does not get unaligned, from Jesper.

15) Fix test_progs kselftest to work with older compilers which are less
    smart in optimizing (and thus throwing build error), from Stanislav.

16) Cleanup and simplify AF_XDP socket teardown, from Björn.

17) Fix sk lookup in BPF kselftest's test_sock_addr with regards
    to netns_id argument, from Andrey.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-20 17:31:36 -08:00
Matt Mullins a38d1107f9 bpf: support raw tracepoints in modules
Distributions build drivers as modules, including network and filesystem
drivers which export numerous tracepoints.  This enables
bpf(BPF_RAW_TRACEPOINT_OPEN) to attach to those tracepoints.

Signed-off-by: Matt Mullins <mmullins@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-12-18 14:08:12 -08:00
Linus Torvalds b5884002dc While running various ftrace tests on new development code, the kmemleak
detector found some allocations that were not freed correctly.
 
 This fixes a couple of leaks in the event trigger code as well as
 in adding function trace filters in trace instances.
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Merge tag 'trace-v4.20-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "While running various ftrace tests on new development code, the
  kmemleak detector found some allocations that were not freed
  correctly.

  This fixes a couple of leaks in the event trigger code as well as in
  adding function trace filters in trace instances"

* tag 'trace-v4.20-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix memory leak of instance function hash filters
  tracing: Fix memory leak in set_trigger_filter()
  tracing: Fix memory leak in create_filter()
2018-12-12 18:15:29 -08:00
Steven Rostedt (VMware) 2840f84f74 tracing: Fix memory leak of instance function hash filters
The following commands will cause a memory leak:

 # cd /sys/kernel/tracing
 # mkdir instances/foo
 # echo schedule > instance/foo/set_ftrace_filter
 # rmdir instances/foo

The reason is that the hashes that hold the filters to set_ftrace_filter and
set_ftrace_notrace are not freed if they contain any data on the instance
and the instance is removed.

Found by kmemleak detector.

Cc: stable@vger.kernel.org
Fixes: 591dffdade ("ftrace: Allow for function tracing instance to filter functions")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-11 13:50:28 -05:00
Steven Rostedt (VMware) 3cec638b3d tracing: Fix memory leak in set_trigger_filter()
When create_event_filter() fails in set_trigger_filter(), the filter may
still be allocated and needs to be freed. The caller expects the
data->filter to be updated with the new filter, even if the new filter
failed (we could add an error message by setting set_str parameter of
create_event_filter(), but that's another update).

But because the error would just exit, filter was left hanging and
nothing could free it.

Found by kmemleak detector.

Cc: stable@vger.kernel.org
Fixes: bac5fb97a1 ("tracing: Add and use generic set_trigger_filter() implementation")
Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-11 13:50:19 -05:00
Steven Rostedt (VMware) b61c19209c tracing: Fix memory leak in create_filter()
The create_filter() calls create_filter_start() which allocates a
"parse_error" descriptor, but fails to call create_filter_finish() that
frees it.

The op_stack and inverts in predicate_parse() were also not freed.

Found by kmemleak detector.

Cc: stable@vger.kernel.org
Fixes: 80765597bc ("tracing: Rewrite filter logic to be simpler and faster")
Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-11 13:50:01 -05:00
Steven Rostedt (VMware) 45fe439bc3 fgraph: Add comment to describe ftrace_graph_get_ret_stack
The ret_stack should not be accessed directly via the curr_ret_stack
variable on the task_struct. This is because the ret_stack is going to be
converted into a series of longs and not an array of ret_stack structures.
The way that a ret_stack should be retrieved is via the
ftrace_graph_get_ret_stack structure, but it needs to be documented on how
to use it.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-10 12:22:45 -05:00
Steven Rostedt (VMware) a0572f687f ftrace: Allow ftrace_replace_code() to be schedulable
The function ftrace_replace_code() is the ftrace engine that does the
work to modify all the nops into the calls to the function callback in
all the functions being traced.

The generic version which is normally called from stop machine, but an
architecture can implement a non stop machine version and still use the
generic ftrace_replace_code(). When an architecture does this,
ftrace_replace_code() may be called from a schedulable context, where
it can allow the code to be preemptible, and schedule out.

In order to allow an architecture to make ftrace_replace_code()
schedulable, a new command flag is added called:

 FTRACE_MAY_SLEEP

Which can be or'd to the command that is passed to
ftrace_modify_all_code() that calls ftrace_replace_code() and will have
it call cond_resched() in the loop that modifies the nops into the
calls to the ftrace trampolines.

Link: http://lkml.kernel.org/r/20181204192903.8193-1-anders.roxell@linaro.org
Link: http://lkml.kernel.org/r/20181205183303.828422192@goodmis.org

Reported-by: Anders Roxell <anders.roxell@linaro.org>
Tested-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-10 12:22:45 -05:00
Masami Hiramatsu 1ce25e9f6f tracing: Add generic event-name based remove event method
Add a generic method to remove event from dynamic event
list. This is same as other system under ftrace. You
just need to pass the event name with '!', e.g.

  # echo p:new_grp/new_event _do_fork > dynamic_events

This creates an event, and

  # echo '!p:new_grp/new_event _do_fork' > dynamic_events

Or,

  # echo '!p:new_grp/new_event' > dynamic_events

will remove new_grp/new_event event.

Note that this doesn't check the event prefix (e.g. "p:")
strictly, because the "group/event" name must be unique.

Link: http://lkml.kernel.org/r/154140869774.17322.8887303560398645347.stgit@devbox

Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-10 12:22:44 -05:00
Steven Rostedt (VMware) 7e1413edd6 tracing: Consolidate trace_add/remove_event_call back to the nolock functions
The trace_add/remove_event_call_nolock() functions were added to allow
the tace_add/remove_event_call() code be called when the event_mutex
lock was already taken. Now that all callers are done within the
event_mutex, there's no reason to have two different interfaces.

Remove the current wrapper trace_add/remove_event_call()s and rename the
_nolock versions back to the original names.

Link: http://lkml.kernel.org/r/154140866955.17322.2081425494660638846.stgit@devbox

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-10 12:22:10 -05:00
Masami Hiramatsu 0e2b81f7b5 tracing: Remove unneeded synth_event_mutex
Rmove unneeded synth_event_mutex. This mutex protects the reference
count in synth_event, however, those operational points are already
protected by event_mutex.

1. In __create_synth_event() and create_or_delete_synth_event(),
 those synth_event_mutex clearly obtained right after event_mutex.

2. event_hist_trigger_func() is trigger_hist_cmd.func() which is
 called by trigger_process_regex(), which is a part of
 event_trigger_regex_write() and this function takes event_mutex.

3. hist_unreg_all() is trigger_hist_cmd.unreg_all() which is called
 by event_trigger_regex_open() and it takes event_mutex.

4. onmatch_destroy() and onmatch_create() have long call tree,
 but both are finally invoked from event_trigger_regex_write()
 and event_trace_del_tracer(), former takes event_mutex, and latter
 ensures called under event_mutex locked.

Finally, I ensured there is no resource conflict. For safety,
I added lockdep_assert_held(&event_mutex) for each function.

Link: http://lkml.kernel.org/r/154140864134.17322.4796059721306031894.stgit@devbox

Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:10 -05:00
Masami Hiramatsu 7bbab38d07 tracing: Use dyn_event framework for synthetic events
Use dyn_event framework for synthetic events. This shows
synthetic events on "tracing/dynamic_events" file in addition
to tracing/synthetic_events interface.

User can also define new events via tracing/dynamic_events
with "s:" prefix. So, the new syntax is below;

  s:[synthetic/]EVENT_NAME TYPE ARG; [TYPE ARG;]...

To remove events via tracing/dynamic_events, you can use
"-:" prefix as same as other events.

Link: http://lkml.kernel.org/r/154140861301.17322.15454611233735614508.stgit@devbox

Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:10 -05:00
Masami Hiramatsu 0597c49c69 tracing/uprobes: Use dyn_event framework for uprobe events
Use dyn_event framework for uprobe events. This shows
uprobe events on "dynamic_events" file.
User can also define new uprobe events via dynamic_events.

Link: http://lkml.kernel.org/r/154140858481.17322.9091293846515154065.stgit@devbox

Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:10 -05:00
Masami Hiramatsu 6212dd2968 tracing/kprobes: Use dyn_event framework for kprobe events
Use dyn_event framework for kprobe events. This shows
kprobe events on "tracing/dynamic_events" file.

User can also define new events via tracing/dynamic_events.

Link: http://lkml.kernel.org/r/154140855646.17322.6619219995865980392.stgit@devbox

Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:09 -05:00
Masami Hiramatsu 5448d44c38 tracing: Add unified dynamic event framework
Add unified dynamic event framework for ftrace kprobes, uprobes
and synthetic events. Those dynamic events can be co-exist on
same file because those syntax doesn't overlap.

This introduces a framework part which provides a unified tracefs
interface and operations.

Link: http://lkml.kernel.org/r/154140852824.17322.12250362185969352095.stgit@devbox

Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:09 -05:00
Masami Hiramatsu d00bbea945 tracing: Integrate similar probe argument parsers
Integrate similar argument parsers for kprobes and uprobes events
into traceprobe_parse_probe_arg().

Link: http://lkml.kernel.org/r/154140850016.17322.9836787731210512176.stgit@devbox

Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:09 -05:00
Masami Hiramatsu faacb361f2 tracing: Simplify creation and deletion of synthetic events
Since the event_mutex and synth_event_mutex ordering issue
is gone, we can skip existing event check when adding or
deleting events, and some redundant code in error path.

This changes release_all_synth_events() to abort the process
when it hits any error and returns the error code. It succeeds
only if it has no error.

Link: http://lkml.kernel.org/r/154140847194.17322.17960275728005067803.stgit@devbox

Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:09 -05:00
Masami Hiramatsu fc800a10be tracing: Lock event_mutex before synth_event_mutex
synthetic event is using synth_event_mutex for protecting
synth_event_list, and event_trigger_write() path acquires
locks as below order.

event_trigger_write(event_mutex)
  ->trigger_process_regex(trigger_cmd_mutex)
    ->event_hist_trigger_func(synth_event_mutex)

On the other hand, synthetic event creation and deletion paths
call trace_add_event_call() and trace_remove_event_call()
which acquires event_mutex. In that case, if we keep the
synth_event_mutex locked while registering/unregistering synthetic
events, its dependency will be inversed.

To avoid this issue, current synthetic event is using a 2 phase
process to create/delete events. For example, it searches existing
events under synth_event_mutex to check for event-name conflicts, and
unlocks synth_event_mutex, then registers a new event under event_mutex
locked. Finally, it locks synth_event_mutex and tries to add the
new event to the list. But it can introduce complexity and a chance
for name conflicts.

To solve this simpler, this introduces trace_add_event_call_nolock()
and trace_remove_event_call_nolock() which don't acquire
event_mutex inside. synthetic event can lock event_mutex before
synth_event_mutex to solve the lock dependency issue simpler.

Link: http://lkml.kernel.org/r/154140844377.17322.13781091165954002713.stgit@devbox

Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:09 -05:00
Masami Hiramatsu 547cd9eacd tracing/uprobes: Add busy check when cleanup all uprobes
Add a busy check loop in cleanup_all_probes() before
trying to remove all events in uprobe_events, the same way
that kprobe_events does.

Without this change, writing null to uprobe_events will
try to remove events but if one of them is enabled, it will
stop there leaving some events cleared and others not clceared.

With this change, writing null to uprobe_events makes
sure all events are not enabled before removing events.
So, it clears all events, or returns an error (-EBUSY)
with keeping all events.

Link: http://lkml.kernel.org/r/154140841557.17322.12653952888762532401.stgit@devbox

Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:08 -05:00
Steven Rostedt (VMware) a7b1d74e87 tracing: Change default buffer_percent to 50
After running several tests, it appears that having the reader wait till
half the buffer is full before starting to read (and causing its own events
to fill up the ring buffer constantly), works well. It keeps trace-cmd (the
main user of this interface) from dominating the traces it records.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:08 -05:00
Steven Rostedt (VMware) 03329f9939 tracing: Add tracefs file buffer_percentage
Add a "buffer_percentage" file, that allows users to specify how much of the
buffer (percentage of pages) need to be filled before waking up a task
blocked on a per cpu trace_pipe_raw file.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:08 -05:00
Steven Rostedt (VMware) 2c2b0a78b3 ring-buffer: Add percentage of ring buffer full to wake up reader
Instead of just waiting for a page to be full before waking up a pending
reader, allow the reader to pass in a "percentage" of pages that have
content before waking up a reader. This should help keep the process of
reading the events not cause wake ups that constantly cause reading of the
buffer.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:08 -05:00
Dan Carpenter ca16b0fbb0 tracing: Have trace_stack nr_entries compare not be so subtle
Dan Carpenter reviewed the trace_stack.c code and figured he found an off by
one bug.

 "From reviewing the code, it seems possible for
  stack_trace_max.nr_entries to be set to .max_entries and in that case we
  would be reading one element beyond the end of the stack_dump_trace[]
  array.  If it's not set to .max_entries then the bug doesn't affect
  runtime."

Although it looks to be the case, it is not. Because we have:

 static unsigned long stack_dump_trace[STACK_TRACE_ENTRIES+1] =
	 { [0 ... (STACK_TRACE_ENTRIES)] = ULONG_MAX };

 struct stack_trace stack_trace_max = {
	.max_entries		= STACK_TRACE_ENTRIES - 1,
	.entries		= &stack_dump_trace[0],
 };

And:

	stack_trace_max.nr_entries = x;
	for (; x < i; x++)
		stack_dump_trace[x] = ULONG_MAX;

Even if nr_entries equals max_entries, indexing with it into the
stack_dump_trace[] array will not overflow the array. But if it is the case,
the second part of the conditional that tests stack_dump_trace[nr_entries]
to ULONG_MAX will always be true.

By applying Dan's patch, it removes the subtle aspect of it and makes the if
conditional slightly more efficient.

Link: http://lkml.kernel.org/r/20180620110758.crunhd5bfep7zuiz@kili.mountain

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:07 -05:00
Steven Rostedt (VMware) b0e21a61d3 function_graph: Have profiler use new helper ftrace_graph_get_ret_stack()
The ret_stack processing is going to change, and that is going
to break anything that is accessing the ret_stack directly. One user is the
function graph profiler. By using the ftrace_graph_get_ret_stack() helper
function, the profiler can access the ret_stack entry without relying on the
implementation details of the stack itself.

Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:07 -05:00
Steven Rostedt (VMware) 76b42b63ed function_graph: Move ftrace_graph_ret_addr() to fgraph.c
Move the function function_graph_ret_addr() to fgraph.c, as the management
of the curr_ret_stack is going to change, and all the accesses to ret_stack
needs to be done in fgraph.c.

Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:07 -05:00
Steven Rostedt (VMware) 688f7089d8 fgraph: Add new fgraph_ops structure to enable function graph hooks
Currently the registering of function graph is to pass in a entry and return
function. We need to have a way to associate those functions together where
the entry can determine to run the return hook. Having a structure that
contains both functions will facilitate the process of converting the code
to be able to do such.

This is similar to the way function hooks are enabled (it passes in
ftrace_ops). Instead of passing in the functions to use, a single structure
is passed in to the registering function.

The unregister function is now passed in the fgraph_ops handle. When we
allow more than one callback to the function graph hooks, this will let the
system know which one to remove.

Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:07 -05:00
Steven Rostedt (VMware) 317e04ca90 tracing: Rearrange functions in trace_sched_wakeup.c
Rearrange the functions in trace_sched_wakeup.c so that there are fewer
 #ifdef CONFIG_FUNCTION_TRACER and #ifdef CONFIG_FUNCTION_GRAPH_TRACER,
instead of having the #ifdefs spread all over.

No functional change is made.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:07 -05:00
Steven Rostedt (VMware) e73e679f65 fgraph: Move function graph specific code into fgraph.c
To make the function graph infrastructure more managable, the code needs to
be in its own file (fgraph.c). Move the code that is specific for managing
the function graph infrastructure out of ftrace.c and into fgraph.c

Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:06 -05:00
Steven Rostedt (VMware) c8dd0f4587 function_graph: Do not expose the graph_time option when profiler is not configured
When the function profiler is not configured, the "graph_time" option is
meaningless, as the function profiler is the only thing that makes use of
it. Do not expose it if the profiler is not configured.

Link: http://lkml.kernel.org/r/20181123061133.GA195223@google.com

Reported-by: Joel Fernandes <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:06 -05:00
Steven Rostedt (VMware) 3306fc4aff ftrace: Create new ftrace_internal.h header
In order to move function graph infrastructure into its own file (fgraph.h)
it needs to access various functions and variables in ftrace.c that are
currently static. Create a new file called ftrace-internal.h that holds the
function prototypes and the extern declarations of the variables needed by
fgraph.c as well, and make them global in ftrace.c such that they can be
used outside that file.

Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:06 -05:00
Steven Rostedt (VMware) 761efe8a94 function_graph: Remove the use of FTRACE_NOTRACE_DEPTH
The curr_ret_stack is no longer set to a negative value when a function is
not to be traced by the function graph tracer. Remove the usage of
FTRACE_NOTRACE_DEPTH, as it is no longer needed.

Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08 20:54:06 -05:00
Dennis Zhou db6638d7d1 blkcg: remove bio->bi_css and instead use bio->bi_blkg
Prior patches ensured that any bio that interacts with a request_queue
is properly associated with a blkg. This makes bio->bi_css unnecessary
as blkg maintains a reference to blkcg already.

This removes the bio field bi_css and transfers corresponding uses to
access via bi_blkg.

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:37 -07:00
Ingo Molnar 4bbfd7467c Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU changes from Paul E. McKenney:

- Convert RCU's BUG_ON() and similar calls to WARN_ON() and similar.

- Replace calls of RCU-bh and RCU-sched update-side functions
  to their vanilla RCU counterparts.  This series is a step
  towards complete removal of the RCU-bh and RCU-sched update-side
  functions.

  ( Note that some of these conversions are going upstream via their
    respective maintainers. )

- Documentation updates, including a number of flavor-consolidation
  updates from Joel Fernandes.

- Miscellaneous fixes.

- Automate generation of the initrd filesystem used for
  rcutorture testing.

- Convert spin_is_locked() assertions to instead use lockdep.

  ( Note that some of these conversions are going upstream via their
    respective maintainers. )

- SRCU updates, especially including a fix from Dennis Krein
  for a bag-on-head-class bug.

- RCU torture-test updates.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-12-04 07:52:30 +01:00
Linus Torvalds 49afe66143 This includes two more fixes:
- Change idx variable in DO_TRACE macro to __idx to avoid name conflicts.
    A kvm event had "idx" as a parameter and it confused the macro.
 
  - Fix a race where interrupts would be traced when set_graph_function was set.
    The previous patch set increased a race window that tricked the function graph
    tracer to think it should trace interrupts when it really should not have.
    The bug has been there before, but was seldom hit. Only the last patch series
    made it more common.
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Merge tag 'trace-v4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull more tracing fixes from Steven Rostedt:
 "Two more fixes:

   - Change idx variable in DO_TRACE macro to __idx to avoid name
     conflicts. A kvm event had "idx" as a parameter and it confused the
     macro.

   - Fix a race where interrupts would be traced when set_graph_function
     was set. The previous patch set increased a race window that
     tricked the function graph tracer to think it should trace
     interrupts when it really should not have.

     The bug has been there before, but was seldom hit. Only the last
     patch series made it more common"

* tag 'trace-v4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing/fgraph: Fix set_graph_function from showing interrupts
  tracepoint: Use __idx instead of idx in DO_TRACE macro to make it unique
2018-11-30 10:40:11 -08:00
Linus Torvalds 0f1f692375 While rewriting the function graph tracer, I discovered a design flaw that
was introduced by a patch that tried to fix one bug, but by doing so created
 another bug. As both bugs corrupt the output (but they do not crash the
 kernel), I decided to fix the design such that it could have both bugs
 fixed. The original fix, fixed time reporting of the function graph tracer
 when doing a max_depth of one. This was code that can test how much the
 kernel interferes with userspace. But in doing so, it could corrupt the time
 keeping of the function profiler.
 
 The issue is that the curr_ret_stack variable was being used for two
 different meanings. One was to keep track of the stack pointer on the
 ret_stack (shadow stack used by the function graph tracer), and the other
 use case was the graph call depth.  Although, the two may be closely
 related, where they got updated was the issue that lead to the two different
 bugs that required the two use cases to be updated differently.
 
 The big issue with this fix is that it requires changing each architecture.
 The good news is, I was able to remove a lot of code that was duplicated
 within the architectures and place it into a single location. Then I could
 make the fix in one place.
 
 I pushed this code into linux-next to let it settle over a week, and before
 doing so, I cross compiled all the affected architectures to make sure that
 they built fine.
 
 In the mean time, I also pulled in a patch that fixes the sched_switch
 previous tasks state output, that was not actually correct.
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Merge tag 'trace-v4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "While rewriting the function graph tracer, I discovered a design flaw
  that was introduced by a patch that tried to fix one bug, but by doing
  so created another bug.

  As both bugs corrupt the output (but they do not crash the kernel), I
  decided to fix the design such that it could have both bugs fixed. The
  original fix, fixed time reporting of the function graph tracer when
  doing a max_depth of one. This was code that can test how much the
  kernel interferes with userspace. But in doing so, it could corrupt
  the time keeping of the function profiler.

  The issue is that the curr_ret_stack variable was being used for two
  different meanings. One was to keep track of the stack pointer on the
  ret_stack (shadow stack used by the function graph tracer), and the
  other use case was the graph call depth. Although, the two may be
  closely related, where they got updated was the issue that lead to the
  two different bugs that required the two use cases to be updated
  differently.

  The big issue with this fix is that it requires changing each
  architecture. The good news is, I was able to remove a lot of code
  that was duplicated within the architectures and place it into a
  single location. Then I could make the fix in one place.

  I pushed this code into linux-next to let it settle over a week, and
  before doing so, I cross compiled all the affected architectures to
  make sure that they built fine.

  In the mean time, I also pulled in a patch that fixes the sched_switch
  previous tasks state output, that was not actually correct"

* tag 'trace-v4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  sched, trace: Fix prev_state output in sched_switch tracepoint
  function_graph: Have profiler use curr_ret_stack and not depth
  function_graph: Reverse the order of pushing the ret_stack and the callback
  function_graph: Move return callback before update of curr_ret_stack
  function_graph: Use new curr_ret_depth to manage depth instead of curr_ret_stack
  function_graph: Make ftrace_push_return_trace() static
  sparc/function_graph: Simplify with function_graph_enter()
  sh/function_graph: Simplify with function_graph_enter()
  s390/function_graph: Simplify with function_graph_enter()
  riscv/function_graph: Simplify with function_graph_enter()
  powerpc/function_graph: Simplify with function_graph_enter()
  parisc: function_graph: Simplify with function_graph_enter()
  nds32: function_graph: Simplify with function_graph_enter()
  MIPS: function_graph: Simplify with function_graph_enter()
  microblaze: function_graph: Simplify with function_graph_enter()
  arm64: function_graph: Simplify with function_graph_enter()
  ARM: function_graph: Simplify with function_graph_enter()
  x86/function_graph: Simplify with function_graph_enter()
  function_graph: Create function_graph_enter() to consolidate architecture code
2018-11-30 09:32:34 -08:00
Steven Rostedt (VMware) 9cd2992f2d fgraph: Have set_graph_notrace only affect function_graph tracer
In order to make the function graph infrastructure more generic, there can
not be code specific for the function_graph tracer in the generic code. This
includes the set_graph_notrace logic, that stops all graph calls when a
function in the set_graph_notrace is hit.

By using the trace_recursion mask, we can use a bit in the current
task_struct to implement the notrace code, and move the logic out of
fgraph.c and into trace_functions_graph.c and keeps it affecting only the
tracer and not all call graph callbacks.

Acked-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-11-29 23:38:34 -05:00
Steven Rostedt (VMware) d864a3ca88 fgraph: Create a fgraph.c file to store function graph infrastructure
As the function graph infrastructure can be used by thing other than
tracing, moving the code to its own file out of the trace_functions_graph.c
code makes more sense.

The fgraph.c file will only contain the infrastructure required to hook into
functions and their return code.

Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-11-29 23:38:34 -05:00
Steven Rostedt (VMware) c43ac4a530 tracing: Do not line wrap short line in function_graph_enter()
Commit 588ca1786f2dd ("function_graph: Use new curr_ret_depth to manage
depth instead of curr_ret_stack") removed a parameter from the call
ftrace_push_return_trace() that made it so that the entire call was under 80
characters, but it did not remove the line break. There's no reason to break
that line up, so make it a single line.

Link: http://lkml.kernel.org/r/20181122100322.GN2131@hirez.programming.kicks-ass.net

Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-11-29 23:38:34 -05:00
Steven Rostedt (VMware) 5cf99a0f31 tracing/fgraph: Fix set_graph_function from showing interrupts
The tracefs file set_graph_function is used to only function graph functions
that are listed in that file (or all functions if the file is empty). The
way this is implemented is that the function graph tracer looks at every
function, and if the current depth is zero and the function matches
something in the file then it will trace that function. When other functions
are called, the depth will be greater than zero (because the original
function will be at depth zero), and all functions will be traced where the
depth is greater than zero.

The issue is that when a function is first entered, and the handler that
checks this logic is called, the depth is set to zero. If an interrupt comes
in and a function in the interrupt handler is traced, its depth will be
greater than zero and it will automatically be traced, even if the original
function was not. But because the logic only looks at depth it may trace
interrupts when it should not be.

The recent design change of the function graph tracer to fix other bugs
caused the depth to be zero while the function graph callback handler is
being called for a longer time, widening the race of this happening. This
bug was actually there for a longer time, but because the race window was so
small it seldom happened. The Fixes tag below is for the commit that widen
the race window, because that commit belongs to a series that will also help
fix the original bug.

Cc: stable@kernel.org
Fixes: 39eb456dac ("function_graph: Use new curr_ret_depth to manage depth instead of curr_ret_stack")
Reported-by: Joe Lawrence <joe.lawrence@redhat.com>
Tested-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-11-29 22:09:00 -05:00
Steven Rostedt (VMware) b1b35f2e21 function_graph: Have profiler use curr_ret_stack and not depth
The profiler uses trace->depth to find its entry on the ret_stack, but the
depth may not match the actual location of where its entry is (if an
interrupt were to preempt the processing of the profiler for another
function, the depth and the curr_ret_stack will be different).

Have it use the curr_ret_stack as the index to find its ret_stack entry
instead of using the depth variable, as that is no longer guaranteed to be
the same.

Cc: stable@kernel.org
Fixes: 03274a3ffb ("tracing/fgraph: Adjust fgraph depth before calling trace return callback")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-11-27 20:31:55 -05:00
Steven Rostedt (VMware) 7c6ea35ef5 function_graph: Reverse the order of pushing the ret_stack and the callback
The function graph profiler uses the ret_stack to store the "subtime" and
reuse it by nested functions and also on the return. But the current logic
has the profiler callback called before the ret_stack is updated, and it is
just modifying the ret_stack that will later be allocated (it's just lucky
that the "subtime" is not touched when it is allocated).

This could also cause a crash if we are at the end of the ret_stack when
this happens.

By reversing the order of the allocating the ret_stack and then calling the
callbacks attached to a function being traced, the ret_stack entry is no
longer used before it is allocated.

Cc: stable@kernel.org
Fixes: 03274a3ffb ("tracing/fgraph: Adjust fgraph depth before calling trace return callback")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-11-27 20:31:54 -05:00
Steven Rostedt (VMware) 552701dd0f function_graph: Move return callback before update of curr_ret_stack
In the past, curr_ret_stack had two functions. One was to denote the depth
of the call graph, the other is to keep track of where on the ret_stack the
data is used. Although they may be slightly related, there are two cases
where they need to be used differently.

The one case is that it keeps the ret_stack data from being corrupted by an
interrupt coming in and overwriting the data still in use. The other is just
to know where the depth of the stack currently is.

The function profiler uses the ret_stack to save a "subtime" variable that
is part of the data on the ret_stack. If curr_ret_stack is modified too
early, then this variable can be corrupted.

The "max_depth" option, when set to 1, will record the first functions going
into the kernel. To see all top functions (when dealing with timings), the
depth variable needs to be lowered before calling the return hook. But by
lowering the curr_ret_stack, it makes the data on the ret_stack still being
used by the return hook susceptible to being overwritten.

Now that there's two variables to handle both cases (curr_ret_depth), we can
move them to the locations where they can handle both cases.

Cc: stable@kernel.org
Fixes: 03274a3ffb ("tracing/fgraph: Adjust fgraph depth before calling trace return callback")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-11-27 20:31:54 -05:00
Steven Rostedt (VMware) 39eb456dac function_graph: Use new curr_ret_depth to manage depth instead of curr_ret_stack
Currently, the depth of the ret_stack is determined by curr_ret_stack index.
The issue is that there's a race between setting of the curr_ret_stack and
calling of the callback attached to the return of the function.

Commit 03274a3ffb ("tracing/fgraph: Adjust fgraph depth before calling
trace return callback") moved the calling of the callback to after the
setting of the curr_ret_stack, even stating that it was safe to do so, when
in fact, it was the reason there was a barrier() there (yes, I should have
commented that barrier()).

Not only does the curr_ret_stack keep track of the current call graph depth,
it also keeps the ret_stack content from being overwritten by new data.

The function profiler, uses the "subtime" variable of ret_stack structure
and by moving the curr_ret_stack, it allows for interrupts to use the same
structure it was using, corrupting the data, and breaking the profiler.

To fix this, there needs to be two variables to handle the call stack depth
and the pointer to where the ret_stack is being used, as they need to change
at two different locations.

Cc: stable@kernel.org
Fixes: 03274a3ffb ("tracing/fgraph: Adjust fgraph depth before calling trace return callback")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-11-27 20:31:54 -05:00
Steven Rostedt (VMware) d125f3f866 function_graph: Make ftrace_push_return_trace() static
As all architectures now call function_graph_enter() to do the entry work,
no architecture should ever call ftrace_push_return_trace(). Make it static.

This is needed to prepare for a fix of a design bug on how the curr_ret_stack
is used.

Cc: stable@kernel.org
Fixes: 03274a3ffb ("tracing/fgraph: Adjust fgraph depth before calling trace return callback")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-11-27 20:31:54 -05:00
Paul E. McKenney 7440172974 tracing: Replace synchronize_sched() and call_rcu_sched()
Now that synchronize_rcu() waits for preempt-disable regions of code
as well as RCU read-side critical sections, synchronize_sched() can
be replaced by synchronize_rcu().  Similarly, call_rcu_sched() can be
replaced by call_rcu().  This commit therefore makes these changes.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: <linux-kernel@vger.kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-11-27 09:21:41 -08:00
Steven Rostedt (VMware) 8114865ff8 function_graph: Create function_graph_enter() to consolidate architecture code
Currently all the architectures do basically the same thing in preparing the
function graph tracer on entry to a function. This code can be pulled into a
generic location and then this will allow the function graph tracer to be
fixed, as well as extended.

Create a new function graph helper function_graph_enter() that will call the
hook function (ftrace_graph_entry) and the shadow stack operation
(ftrace_push_return_trace), and remove the need of the architecture code to
manage the shadow stack.

This is needed to prepare for a fix of a design bug on how the curr_ret_stack
is used.

Cc: stable@kernel.org
Fixes: 03274a3ffb ("tracing/fgraph: Adjust fgraph depth before calling trace return callback")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-11-26 16:18:04 -05:00
Martynas Pumputis 1efb6ee3ed bpf: fix check of allowed specifiers in bpf_trace_printk
A format string consisting of "%p" or "%s" followed by an invalid
specifier (e.g. "%p%\n" or "%s%") could pass the check which
would make format_decode (lib/vsprintf.c) to warn.

Fixes: 9c959c863f ("tracing: Allow BPF programs to call bpf_trace_printk()")
Reported-by: syzbot+1ec5c5ec949c4adaa0c4@syzkaller.appspotmail.com
Signed-off-by: Martynas Pumputis <m@lambda.lt>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-11-23 21:54:14 +01:00
Masami Hiramatsu ee474b81fe tracing/kprobes: Fix strpbrk() argument order
Fix strpbrk()'s argument order, it must pass acceptable string
in 2nd argument. Note that this can cause a kernel panic where
it recovers backup character to code->data.

Link: http://lkml.kernel.org/r/154108256792.2604.1816052586385217811.stgit@devbox

Fixes: a6682814f3 ("tracing/kprobes: Allow kprobe-events to record module symbol")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-11-05 09:47:14 -05:00
Linus Torvalds 5f21585384 for-linus-20181102
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Merge tag 'for-linus-20181102' of git://git.kernel.dk/linux-block

Pull block layer fixes from Jens Axboe:
 "The biggest part of this pull request is the revert of the blkcg
  cleanup series. It had one fix earlier for a stacked device issue, but
  another one was reported. Rather than play whack-a-mole with this,
  revert the entire series and try again for the next kernel release.

  Apart from that, only small fixes/changes.

  Summary:

   - Indentation fixup for mtip32xx (Colin Ian King)

   - The blkcg cleanup series revert (Dennis Zhou)

   - Two NVMe fixes. One fixing a regression in the nvme request
     initialization in this merge window, causing nvme-fc to not work.
     The other is a suspend/resume p2p resource issue (James, Keith)

   - Fix sg discard merge, allowing us to merge in cases where we didn't
     before (Jianchao Wang)

   - Call rq_qos_exit() after the queue is frozen, preventing a hang
     (Ming)

   - Fix brd queue setup, fixing an oops if we fail setting up all
     devices (Ming)"

* tag 'for-linus-20181102' of git://git.kernel.dk/linux-block:
  nvme-pci: fix conflicting p2p resource adds
  nvme-fc: fix request private initialization
  blkcg: revert blkcg cleanups series
  block: brd: associate with queue until adding disk
  block: call rq_qos_exit() after queue is frozen
  mtip32xx: clean an indentation issue, remove extraneous tabs
  block: fix the DISCARD request merge
2018-11-02 11:25:48 -07:00
Dennis Zhou b5f2954d30 blkcg: revert blkcg cleanups series
This reverts a series committed earlier due to null pointer exception
bug report in [1]. It seems there are edge case interactions that I did
not consider and will need some time to understand what causes the
adverse interactions.

The original series can be found in [2] with a follow up series in [3].

[1] https://www.spinics.net/lists/cgroups/msg20719.html
[2] https://lore.kernel.org/lkml/20180911184137.35897-1-dennisszhou@gmail.com/
[3] https://lore.kernel.org/lkml/20181020185612.51587-1-dennis@kernel.org/

This reverts the following commits:
d459d853c2, b2c3fa5467, 101246ec02, b3b9f24f5f, e2b0989954,
f0fcb3ec89, c839e7a03f, bdc2491708, 74b7c02a9b, 5bf9a1f3b4,
a7b39b4e96, 07b05bcc32, 49f4c2dc2b, 27e6fa996c

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-01 19:59:53 -06:00
Linus Torvalds eb7046e9bf platform-drivers-x86 for v4.20-1
Move the Dell dcdbas and dell_rbu drivers into platform/drivers/x86 as
 they are closely coupled with other drivers in this location.
 
 Improve _init* usage for acerhdf and fix some usage issues with messages
 and module parameters.
 
 Simplify asus-wmi by calling ACPI/WMI methods directly, eliminating
 workqueue overhead, eliminate double reporting of keyboard backlight.
 
 Fix wake from USB failure on Bay Trail devices (intel_int0002_vgpio).
 
 Notify intel_telemetry users when IPC1 device is not enabled.
 
 Update various drivers with new laptop model IDs.
 
 Update several intel drivers to use SPDX identifers and order headers
 alphabetically.
 
 The following is an automated git shortlog grouped by driver:
 
 Add Intel AtomISP2 dummy / power-management driver:
  - Add Intel AtomISP2 dummy / power-management driver
 
 lg-laptop:
  - Add LG Gram laptop special features driver
 
 HID:
  -  asus: only support backlight when it's not driven by WMI
 
 MAINTAINERS:
  -  intel_telemetry: Update maintainers info
  -  intel_pmc_core: Update MAINTAINERS
  -  Update maintainer for dcdbas and dell_rbu
  -  Use my infradead account exclusively for PDx86 work
 
 acerhdf:
  -  restructure to allow large BIOS table be __initconst
  -  mark appropriate content with __init prefix
  -  Add BIOS entry for Gateway LT31 v1.3307
  -  Remove cut-and-paste trap from instructions
  -  Enable ability to list supported systems
  -  clarify modinfo messages for BIOS override
 
 asus-wmi:
  -  export function for evaluating WMI methods
  -  Only notify kbd LED hw_change by fn-key pressed
  -  Simplify the keyboard brightness updating process
 
 firmware:
  -  dcdbas: include linux/io.h
  -  dcdbas: Move dcdbas to drivers/platform/x86
  -  dell_rbu: Move dell_rbu to drivers/platform/x86
  -  dcdbas: Add support for WSMT ACPI table
  -  dell_rbu: Make payload memory uncachable
 
 ideapad-laptop:
  -  Add Y530-15ICH to no_hw_rfkill
  -  Use __func__ instead of read_ec_cmd in pr_err
 
 intel-hid:
  -  Convert to use SPDX identifier
 
 intel-ips:
  -  Convert to use SPDX identifier
 
 intel-rst:
  -  Convert to use SPDX identifier
  -  Sort headers alphabetically
 
 intel-smartconnect:
  -  Convert to use SPDX identifier
  -  Sort headers alphabetically
 
 intel-wmi-thunderbolt:
  -  Add dynamic debugging
  -  Convert to use SPDX identifier
 
 intel_bxtwc_tmu:
  -  Convert to use SPDX identifier
 
 intel_cht_int33fe:
  -  Convert to use SPDX identifier
 
 intel_chtdc_ti_pwrbtn:
  -  Add SPDX identifier
 
 intel_int0002_vgpio:
  -  Convert to use SPDX identifier
  -  Implement irq_set_wake
  -  Enable the driver on Bay Trail platforms
 
 intel_menlow:
  -  Convert to use SPDX identifier
  -  Sort headers alphabetically
 
 intel_mid_powerbtn:
  -  Convert to use SPDX identifier
  -  Remove unnecessary init.h inclusion
  -  Get rid of custom ICPU() macro
 
 intel_mid_thermal:
  -  Convert to use SPDX identifier
  -  Sort headers alphabetically
 
 intel_oaktrail:
  -  Convert to use SPDX identifier
  -  Sort headers alphabetically
 
 intel_pmc:
  -  Convert to use SPDX identifier
  -  Sort headers alphabetically
 
 intel_punit_ipc:
  -  Convert to use SPDX identifier
  -  Sort headers alphabetically
 
 intel_scu_ipc:
  -  Convert to use SPDX identifier
  -  Sort headers alphabetically
 
 intel_telemetry:
  -  Get rid of custom macro
  -  report debugfs failure
  -  Convert to use SPDX identifier
 
 intel_turbo_max_3:
  -  Convert to use SPDX identifier
  -  Sort headers alphabetically
 
 mlx-platform:
  -  Properly use mlxplat_mlxcpld_msn201x_items
 
 touchscreen_dmi:
  -  Add min-x and min-y settings for various models
  -  Add info for the Onda V80 Plus v3 tablet
  -  Add info for the Trekstor Primetab T13B tablet
  -  Add info for the Trekstor Primebook C11 convertible
 
 tracing:
  -  Trivia spelling fix containerof() -> container_of()
 
 wmi:
  -  declare device_type structure as constant
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Merge tag 'platform-drivers-x86-v4.20-1' of git://git.infradead.org/linux-platform-drivers-x86

Pull x86 platform driver updates from Darren Hart:

 - Move the Dell dcdbas and dell_rbu drivers into platform/drivers/x86
   as they are closely coupled with other drivers in this location.

 - Improve _init* usage for acerhdf and fix some usage issues with
   messages and module parameters.

 - Simplify asus-wmi by calling ACPI/WMI methods directly, eliminating
   workqueue overhead, eliminate double reporting of keyboard backlight.

 - Fix wake from USB failure on Bay Trail devices (intel_int0002_vgpio).

 - Notify intel_telemetry users when IPC1 device is not enabled.

 - Update various drivers with new laptop model IDs.

 - Update several intel drivers to use SPDX identifers and order headers
   alphabetically.

* tag 'platform-drivers-x86-v4.20-1' of git://git.infradead.org/linux-platform-drivers-x86: (64 commits)
  HID: asus: only support backlight when it's not driven by WMI
  platform/x86: asus-wmi: export function for evaluating WMI methods
  platform/x86: asus-wmi: Only notify kbd LED hw_change by fn-key pressed
  platform/x86: wmi: declare device_type structure as constant
  platform/x86: ideapad: Add Y530-15ICH to no_hw_rfkill
  platform/x86: Add Intel AtomISP2 dummy / power-management driver
  platform/x86: touchscreen_dmi: Add min-x and min-y settings for various models
  platform/x86: touchscreen_dmi: Add info for the Onda V80 Plus v3 tablet
  platform/x86: touchscreen_dmi: Add info for the Trekstor Primetab T13B tablet
  platform/x86: intel_telemetry: Get rid of custom macro
  platform/x86: intel_telemetry: report debugfs failure
  MAINTAINERS: intel_telemetry: Update maintainers info
  platform/x86: Add LG Gram laptop special features driver
  platform/x86: asus-wmi: Simplify the keyboard brightness updating process
  platform/x86: touchscreen_dmi: Add info for the Trekstor Primebook C11 convertible
  platform/x86: mlx-platform: Properly use mlxplat_mlxcpld_msn201x_items
  MAINTAINERS: intel_pmc_core: Update MAINTAINERS
  firmware: dcdbas: include linux/io.h
  platform/x86: intel-wmi-thunderbolt: Add dynamic debugging
  platform/x86: intel-wmi-thunderbolt: Convert to use SPDX identifier
  ...
2018-11-01 08:42:21 -07:00
Linus Torvalds 343a9f3540 The biggest change here is the updates to kprobes
Back in January I posted patches to create function based events. These were
 the events that you suggested I make to allow developers to easily create
 events in code where no trace event exists. After posting those changes for
 review, it was suggested that we implement this instead with kprobes.
 
 The problem with kprobes is that the interface is too complex and needs to
 be simplified. Masami Hiramatsu posted patches in March and I've been
 playing with them a bit. There's been a bit of clean up in the kprobe code
 that was inspired by the function based event patches, and a couple of
 enhancements to the kprobe event interface.
 
  - If the arch supports it (we added support for x86), you can place a
    kprobe event at the start of a function and use $arg1, $arg2, etc
    to reference the arguments of a function. (Before you needed to know
    what register or where on the stack the argument was).
 
  - The second is a way to see array of events. For example, if you reference
    a mac address, you can add:
 
    echo 'p:mac ip_rcv perm_addr=+574($arg2):x8[6]' > kprobe_events
 
    And this will produce:
 
    mac: (ip_rcv+0x0/0x140) perm_addr={0x52,0x54,0x0,0xc0,0x76,0xec}
 
 Other changes include
 
  - Exporting trace_dump_stack to modules
 
  - Have the stack tracer trace the entire stack (stop trying to remove
    tracing itself, as we keep removing too much).
 
  - Added support for SDT in uprobes
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Merge tag 'trace-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "The biggest change here is the updates to kprobes

  Back in January I posted patches to create function based events.
  These were the events that you suggested I make to allow developers to
  easily create events in code where no trace event exists. After
  posting those changes for review, it was suggested that we implement
  this instead with kprobes.

  The problem with kprobes is that the interface is too complex and
  needs to be simplified. Masami Hiramatsu posted patches in March and
  I've been playing with them a bit. There's been a bit of clean up in
  the kprobe code that was inspired by the function based event patches,
  and a couple of enhancements to the kprobe event interface.

   - If the arch supports it (we added support for x86), you can place a
     kprobe event at the start of a function and use $arg1, $arg2, etc
     to reference the arguments of a function. (Before you needed to
     know what register or where on the stack the argument was).

   - The second is a way to see array of events. For example, if you
     reference a mac address, you can add:

	echo 'p:mac ip_rcv perm_addr=+574($arg2):x8[6]' > kprobe_events

     And this will produce:

	mac: (ip_rcv+0x0/0x140) perm_addr={0x52,0x54,0x0,0xc0,0x76,0xec}

  Other changes include

   - Exporting trace_dump_stack to modules

   - Have the stack tracer trace the entire stack (stop trying to remove
     tracing itself, as we keep removing too much).

   - Added support for SDT in uprobes"

[ SDT - "Statically Defined Tracing" are userspace markers for tracing.
  Let's not use random TLA's in explanations unless they are fairly
  well-established as generic (at least for kernel people) - Linus ]

* tag 'trace-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (24 commits)
  tracing: Have stack tracer trace full stack
  tracing: Export trace_dump_stack to modules
  tracing: probeevent: Fix uninitialized used of offset in parse args
  tracing/kprobes: Allow kprobe-events to record module symbol
  tracing/kprobes: Check the probe on unloaded module correctly
  tracing/uprobes: Fix to return -EFAULT if copy_from_user failed
  tracing: probeevent: Add $argN for accessing function args
  x86: ptrace: Add function argument access API
  tracing: probeevent: Add array type support
  tracing: probeevent: Add symbol type
  tracing: probeevent: Unify fetch_insn processing common part
  tracing: probeevent: Append traceprobe_ for exported function
  tracing: probeevent: Return consumed bytes of dynamic area
  tracing: probeevent: Unify fetch type tables
  tracing: probeevent: Introduce new argument fetching code
  tracing: probeevent: Remove NOKPROBE_SYMBOL from print functions
  tracing: probeevent: Cleanup argument field definition
  tracing: probeevent: Cleanup print argument functions
  trace_uprobe: support reference counter in fd-based uprobe
  perf probe: Support SDT markers having reference counter (semaphore)
  ...
2018-10-30 09:49:56 -07:00
Linus Torvalds f4267b3604 Masami had a couple more fixes to the synthetic events. One was a proper
error return value, and the other is for the self tests.
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Merge tag 'trace-v4.19-rc8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Masami had a couple more fixes to the synthetic events. One was a
  proper error return value, and the other is for the self tests"

* tag 'trace-v4.19-rc8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  selftests/ftrace: Fix synthetic event test to delete event correctly
  tracing: Return -ENOENT if there is no target synthetic event
2018-10-30 09:47:28 -07:00
Masami Hiramatsu 18858511fd tracing: Return -ENOENT if there is no target synthetic event
Return -ENOENT error if there is no target synthetic event.
This notices an operation failure to user as below;

  # echo 'wakeup_latency u64 lat; pid_t pid;' > synthetic_events
  # echo '!wakeup' >> synthetic_events
  sh: write error: No such file or directory

Link: http://lkml.kernel.org/r/154013449986.25576.9487131386597290172.stgit@devbox

Acked-by: Tom Zanussi <zanussi@linux.intel.com>
Tested-by: Tom Zanussi <zanussi@linux.intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Rajvi Jingar <rajvi.jingar@intel.com>
Cc: stable@vger.kernel.org
Fixes: 4b147936fa ('tracing: Add support for 'synthetic' events')
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-28 04:58:15 -04:00
Steven Rostedt (VMware) a2acce5369 tracing: Have stack tracer trace full stack
The stack tracer traces every function call checking the current stack (in
non interrupt context), looking for the deepest stack, and saving it when it
finds a new max depth. The problem is that it calls save_stack_trace(), and
with the new ORC unwinder, it can skip too much. As it looks at the ip of
the function call in the backtrace to find where it should start, it doesn't
need to skip anything.

The stack trace selftest would fail when the kernel was complied with the
ORC UNDWINDER enabled. Without skipping functions when doing the stack
trace, it now passes again.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-27 11:15:04 -04:00
Nikolay Borisov da387e5c93 tracing: Export trace_dump_stack to modules
There is no reason for this function to be unexprted and it's a useful
debugging aid.

Link: http://lkml.kernel.org/r/1539759103-5923-1-git-send-email-nborisov@suse.com

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-27 11:15:03 -04:00
Linus Torvalds 6ab9e09238 for-4.20/block-20181021
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Merge tag 'for-4.20/block-20181021' of git://git.kernel.dk/linux-block

Pull block layer updates from Jens Axboe:
 "This is the main pull request for block changes for 4.20. This
  contains:

   - Series enabling runtime PM for blk-mq (Bart).

   - Two pull requests from Christoph for NVMe, with items such as;
      - Better AEN tracking
      - Multipath improvements
      - RDMA fixes
      - Rework of FC for target removal
      - Fixes for issues identified by static checkers
      - Fabric cleanups, as prep for TCP transport
      - Various cleanups and bug fixes

   - Block merging cleanups (Christoph)

   - Conversion of drivers to generic DMA mapping API (Christoph)

   - Series fixing ref count issues with blkcg (Dennis)

   - Series improving BFQ heuristics (Paolo, et al)

   - Series improving heuristics for the Kyber IO scheduler (Omar)

   - Removal of dangerous bio_rewind_iter() API (Ming)

   - Apply single queue IPI redirection logic to blk-mq (Ming)

   - Set of fixes and improvements for bcache (Coly et al)

   - Series closing a hotplug race with sysfs group attributes (Hannes)

   - Set of patches for lightnvm:
      - pblk trace support (Hans)
      - SPDX license header update (Javier)
      - Tons of refactoring patches to cleanly abstract the 1.2 and 2.0
        specs behind a common core interface. (Javier, Matias)
      - Enable pblk to use a common interface to retrieve chunk metadata
        (Matias)
      - Bug fixes (Various)

   - Set of fixes and updates to the blk IO latency target (Josef)

   - blk-mq queue number updates fixes (Jianchao)

   - Convert a bunch of drivers from the old legacy IO interface to
     blk-mq. This will conclude with the removal of the legacy IO
     interface itself in 4.21, with the rest of the drivers (me, Omar)

   - Removal of the DAC960 driver. The SCSI tree will introduce two
     replacement drivers for this (Hannes)"

* tag 'for-4.20/block-20181021' of git://git.kernel.dk/linux-block: (204 commits)
  block: setup bounce bio_sets properly
  blkcg: reassociate bios when make_request() is called recursively
  blkcg: fix edge case for blk_get_rl() under memory pressure
  nvme-fabrics: move controller options matching to fabrics
  nvme-rdma: always have a valid trsvcid
  mtip32xx: fully switch to the generic DMA API
  rsxx: switch to the generic DMA API
  umem: switch to the generic DMA API
  sx8: switch to the generic DMA API
  sx8: remove dead IF_64BIT_DMA_IS_POSSIBLE code
  skd: switch to the generic DMA API
  ubd: remove use of blk_rq_map_sg
  nvme-pci: remove duplicate check
  drivers/block: Remove DAC960 driver
  nvme-pci: fix hot removal during error handling
  nvmet-fcloop: suppress a compiler warning
  nvme-core: make implicit seed truncation explicit
  nvmet-fc: fix kernel-doc headers
  nvme-fc: rework the request initialization code
  nvme-fc: introduce struct nvme_fcp_op_w_sgl
  ...
2018-10-22 17:46:08 +01:00
Masami Hiramatsu a360d9e401 tracing: Fix synthetic event to allow semicolon at end
Fix synthetic event to allow independent semicolon at end.

The synthetic_events interface accepts a semicolon after the
last word if there is no space.

 # echo "myevent u64 var;" >> synthetic_events

But if there is a space, it returns an error.

 # echo "myevent u64 var ;" > synthetic_events
 sh: write error: Invalid argument

This behavior is difficult for users to understand. Let's
allow the last independent semicolon too.

Link: http://lkml.kernel.org/r/153986835420.18251.2191216690677025744.stgit@devbox

Cc: Shuah Khan <shuah@kernel.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: stable@vger.kernel.org
Fixes: commit 4b147936fa ("tracing: Add support for 'synthetic' events")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-19 17:25:11 -04:00
Masami Hiramatsu 282447ba6b tracing: Fix synthetic event to accept unsigned modifier
Fix synthetic event to accept unsigned modifier for its field type
correctly.

Currently, synthetic_events interface returns error for "unsigned"
modifiers as below;

 # echo "myevent unsigned long var" >> synthetic_events
 sh: write error: Invalid argument

This is because argv_split() breaks "unsigned long" into "unsigned"
and "long", but parse_synth_field() doesn't expected it.

With this fix, synthetic_events can handle the "unsigned long"
correctly like as below;

 # echo "myevent unsigned long var" >> synthetic_events
 # cat synthetic_events
 myevent	unsigned long var

Link: http://lkml.kernel.org/r/153986832571.18251.8448135724590496531.stgit@devbox

Cc: Shuah Khan <shuah@kernel.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: stable@vger.kernel.org
Fixes: commit 4b147936fa ("tracing: Add support for 'synthetic' events")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-19 17:25:11 -04:00
Steven Rostedt (VMware) 12ad0cb212 tracing: Use trace_clock_local() for looping in preemptirq_delay_test.c
The preemptirq_delay_test module is used for the ftrace selftest code that
tests the latency tracers. The problem is that it uses ktime for the delay
loop, and then checks the tracer to see if the delay loop is caught, but the
tracer uses trace_clock_local() which uses various different other clocks to
measure the latency. As ktime uses the clock cycles, and the code then
converts that to nanoseconds, it causes rounding errors, and the preemptirq
latency tests are failing due to being off by 1 (it expects to see a delay
of 500000 us, but the delay is only 499999 us). This is happening due to a
rounding error in the ktime (which is totally legit). The purpose of the
test is to see if it can catch the delay, not to test the accuracy between
trace_clock_local() and ktime_get(). Best to use apples to apples, and have
the delay loop use the same clock as the latency tracer does.

Cc: stable@vger.kernel.org
Fixes: f96e8577da ("lib: Add module for testing preemptoff/irqsoff latency tracers")
Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-17 15:35:33 -04:00
Steven Rostedt (VMware) bf173ca92d tracing: probeevent: Fix uninitialized used of offset in parse args
Dan's smatch utility found an uninitialized use of offset in a path in
parse_probe_args(). Unless an offset is specifically specified for commands
that allow them, it should default to zero.

Link: http://lkml.kernel.org/r/20181012134246.5doqaobxunlqqs53@mwanda
Fixes: 533059281e ("tracing: probeevent: Introduce new argument fetching code")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch)
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-12 12:50:22 -04:00
Masami Hiramatsu a6682814f3 tracing/kprobes: Allow kprobe-events to record module symbol
Allow kprobe-events to record module symbols.

Since data symbols in a non-loaded module doesn't exist, it fails to
define such symbol as an argument of kprobe-event. But if the kprobe
event is defined on that module, we can defer to resolve the symbol
address.

Note that if given symbol is not found, the event is kept unavailable.
User can enable it but the event is not recorded.

Link: http://lkml.kernel.org/r/153547312336.26502.11432902826345374463.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10 22:19:12 -04:00
Masami Hiramatsu 59158ec4ae tracing/kprobes: Check the probe on unloaded module correctly
Current kprobe event doesn't checks correctly whether the
given event is on unloaded module or not. It just checks
the event has ":" in the name.

That is not enough because if we define a probe on non-exist
symbol on loaded module, it allows to define that (with
warning message)

To ensure it correctly, this searches the module name on
loaded module list and only if there is not, it allows to
define it. (this event will be available when the target
module is loaded)

Link: http://lkml.kernel.org/r/153547309528.26502.8300278470528281328.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10 22:19:12 -04:00
Masami Hiramatsu f3f58935ed tracing/uprobes: Fix to return -EFAULT if copy_from_user failed
Fix probe_mem_read() to return -EFAULT if copy_from_user()
failed. The copy_from_user() returns remaining bytes
when it failed, but probe_mem_read() caller expects it
returns error code like as probe_kernel_read().

Link: http://lkml.kernel.org/r/153547306719.26502.8353484532699160223.stgit@devbox

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10 22:19:11 -04:00
Masami Hiramatsu a1303af5d7 tracing: probeevent: Add $argN for accessing function args
Add $argN special fetch variable for accessing function
arguments. This allows user to trace the Nth argument easily
at the function entry.

Note that this returns most probably assignment of registers
and stacks. In some case, it may not work well. If you need
to access correct registers or stacks you should use perf-probe.

Link: http://lkml.kernel.org/r/152465888632.26224.3412465701570253696.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10 22:19:11 -04:00
Masami Hiramatsu 40b53b7718 tracing: probeevent: Add array type support
Add array type support for probe events.
This allows user to get arraied types from memory address.
The array type syntax is

	TYPE[N]

Where TYPE is one of types (u8/16/32/64,s8/16/32/64,
x8/16/32/64, symbol, string) and N is a fixed value less
than 64.

The string array type is a bit different from other types. For
other base types, <base-type>[1] is equal to <base-type>
(e.g. +0(%di):x32[1] is same as +0(%di):x32.) But string[1] is not
equal to string. The string type itself represents "char array",
but string array type represents "char * array". So, for example,
+0(%di):string[1] is equal to +0(+0(%di)):string.

Link: http://lkml.kernel.org/r/152465891533.26224.6150658225601339931.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10 22:19:10 -04:00
Masami Hiramatsu 60c2e0cebf tracing: probeevent: Add symbol type
Add "symbol" type to probeevent, which is an alias of u32 or u64
(depends on BITS_PER_LONG). This shows the result value in
symbol+offset style. This type is only available with kprobe
events.

Link: http://lkml.kernel.org/r/152465882860.26224.14779072294412467338.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10 22:19:10 -04:00
Masami Hiramatsu 9b960a3883 tracing: probeevent: Unify fetch_insn processing common part
Unify the fetch_insn bottom process (from stage 2: dereference
indirect data) from kprobe and uprobe events, since those are
mostly same.

Link: http://lkml.kernel.org/r/152465879965.26224.8547240824606804815.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10 22:19:09 -04:00
Masami Hiramatsu 0a46c8549f tracing: probeevent: Append traceprobe_ for exported function
Append traceprobe_ for exported function set_print_fmt() as
same as other functions.

Link: http://lkml.kernel.org/r/152465877071.26224.11143125027282999726.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10 22:19:09 -04:00
Masami Hiramatsu 9178412ddf tracing: probeevent: Return consumed bytes of dynamic area
Cleanup string fetching routine so that returns the consumed
bytes of dynamic area and store the string information as
data_loc format instead of data_rloc.
This simplifies the fetcharg loop.

Link: http://lkml.kernel.org/r/152465874163.26224.12125143907501289031.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10 22:19:08 -04:00
Masami Hiramatsu f451bc89d8 tracing: probeevent: Unify fetch type tables
Unify {k,u}probe_fetch_type_table to probe_fetch_type_table
because the main difference of those type tables (fetcharg
methods) are gone. Now we can consolidate it.

Link: http://lkml.kernel.org/r/152465871274.26224.13999436317830479698.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10 22:19:08 -04:00
Masami Hiramatsu 533059281e tracing: probeevent: Introduce new argument fetching code
Replace {k,u}probe event argument fetching framework with switch-case based.
Currently that is implemented with structures, macros and chain of
function-pointers, which is more complicated than necessary and may get a
performance penalty by retpoline.

This simplify that with an array of "fetch_insn" (opcode and oprands), and
make process_fetch_insn() just interprets it. No function pointers are used.

Link: http://lkml.kernel.org/r/152465868340.26224.2551120475197839464.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10 22:19:07 -04:00
Masami Hiramatsu 7bfbc63eda tracing: probeevent: Remove NOKPROBE_SYMBOL from print functions
Remove unneeded NOKPROBE_SYMBOL from print functions since
the print functions are only used when printing out the
trace data, and not from kprobe handler.

Link: http://lkml.kernel.org/r/152465865422.26224.10111548170594014954.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10 22:19:07 -04:00
Masami Hiramatsu eeb07b0615 tracing: probeevent: Cleanup argument field definition
Cleanup event argument definition code in one place for
maintenancability.

Link: http://lkml.kernel.org/r/152465862529.26224.9068605421476018902.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10 22:19:06 -04:00
Masami Hiramatsu 56de763052 tracing: probeevent: Cleanup print argument functions
Cleanup the print-argument function to decouple it into
print-name and print-value, so that it can support more
flexible expression, like array type.

Link: http://lkml.kernel.org/r/152465859635.26224.13452846788717102315.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10 22:19:06 -04:00
Song Liu a6ca88b241 trace_uprobe: support reference counter in fd-based uprobe
This patch enables uprobes with reference counter in fd-based uprobe.
Highest 32 bits of perf_event_attr.config is used to stored offset
of the reference count (semaphore).

Format information in /sys/bus/event_source/devices/uprobe/format/ is
updated to reflect this new feature.

Link: http://lkml.kernel.org/r/20181002053636.1896903-1-songliubraving@fb.com

Cc: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10 22:14:17 -04:00
Jens Axboe c0aac682fa This is the 4.19-rc6 release
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Merge tag 'v4.19-rc6' into for-4.20/block

Merge -rc6 in, for two reasons:

1) Resolve a trivial conflict in the blk-mq-tag.c documentation
2) A few important regression fixes went into upstream directly, so
   they aren't in the 4.20 branch.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

* tag 'v4.19-rc6': (780 commits)
  Linux 4.19-rc6
  MAINTAINERS: fix reference to moved drivers/{misc => auxdisplay}/panel.c
  cpufreq: qcom-kryo: Fix section annotations
  perf/core: Add sanity check to deal with pinned event failure
  xen/blkfront: correct purging of persistent grants
  Revert "xen/blkfront: When purging persistent grants, keep them in the buffer"
  selftests/powerpc: Fix Makefiles for headers_install change
  blk-mq: I/O and timer unplugs are inverted in blktrace
  dax: Fix deadlock in dax_lock_mapping_entry()
  x86/boot: Fix kexec booting failure in the SEV bit detection code
  bcache: add separate workqueue for journal_write to avoid deadlock
  drm/amd/display: Fix Edid emulation for linux
  drm/amd/display: Fix Vega10 lightup on S3 resume
  drm/amdgpu: Fix vce work queue was not cancelled when suspend
  Revert "drm/panel: Add device_link from panel device to DRM device"
  xen/blkfront: When purging persistent grants, keep them in the buffer
  clocksource/drivers/timer-atmel-pit: Properly handle error cases
  block: fix deadline elevator drain for zoned block devices
  ACPI / hotplug / PCI: Don't scan for non-hotplug bridges if slot is not bridge
  drm/syncobj: Don't leak fences when WAIT_FOR_SUBMIT is set
  ...

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-10-01 08:58:57 -06:00
Andy Shevchenko ca9184f079 tracing: Trivia spelling fix containerof() -> container_of()
This is the only location on kernel that has wrong spelling
of the container_of() helper. Fix it.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2018-09-26 12:21:00 +03:00
Ravi Bangoria ccea8727dc trace_uprobe/sdt: Prevent multiple reference counter for same uprobe
We assume to have only one reference counter for one uprobe.
Don't allow user to add multiple trace_uprobe entries having
same inode+offset but different reference counter.

Ex,
  # echo "p:sdt_tick/loop2 /home/ravi/tick:0x6e4(0x10036)" > uprobe_events
  # echo "p:sdt_tick/loop2_1 /home/ravi/tick:0x6e4(0xfffff)" >> uprobe_events
  bash: echo: write error: Invalid argument

  # dmesg
  trace_kprobe: Reference counter offset mismatch.

There is one exception though:
When user is trying to replace the old entry with the new
one, we allow this if the new entry does not conflict with
any other existing entries.

Link: http://lkml.kernel.org/r/20180820044250.11659-4-ravi.bangoria@linux.ibm.com

Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reviewed-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Tested-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-09-24 04:44:54 -04:00
Ravi Bangoria 1cc33161a8 uprobes: Support SDT markers having reference count (semaphore)
Userspace Statically Defined Tracepoints[1] are dtrace style markers
inside userspace applications. Applications like PostgreSQL, MySQL,
Pthread, Perl, Python, Java, Ruby, Node.js, libvirt, QEMU, glib etc
have these markers embedded in them. These markers are added by developer
at important places in the code. Each marker source expands to a single
nop instruction in the compiled code but there may be additional
overhead for computing the marker arguments which expands to couple of
instructions. In case the overhead is more, execution of it can be
omitted by runtime if() condition when no one is tracing on the marker:

    if (reference_counter > 0) {
        Execute marker instructions;
    }

Default value of reference counter is 0. Tracer has to increment the
reference counter before tracing on a marker and decrement it when
done with the tracing.

Implement the reference counter logic in core uprobe. User will be
able to use it from trace_uprobe as well as from kernel module. New
trace_uprobe definition with reference counter will now be:

    <path>:<offset>[(ref_ctr_offset)]

where ref_ctr_offset is an optional field. For kernel module, new
variant of uprobe_register() has been introduced:

    uprobe_register_refctr(inode, offset, ref_ctr_offset, consumer)

No new variant for uprobe_unregister() because it's assumed to have
only one reference counter for one uprobe.

[1] https://sourceware.org/systemtap/wiki/UserSpaceProbeImplementation

Note: 'reference counter' is called as 'semaphore' in original Dtrace
(or Systemtap, bcc and even in ELF) documentation and code. But the
term 'semaphore' is misleading in this context. This is just a counter
used to hold number of tracers tracing on a marker. This is not really
used for any synchronization. So we are calling it a 'reference counter'
in kernel / perf code.

Link: http://lkml.kernel.org/r/20180820044250.11659-2-ravi.bangoria@linux.ibm.com

Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
[Only trace_uprobe.c]
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Song Liu <songliubraving@fb.com>
Tested-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-09-24 04:44:53 -04:00
Steven Rostedt (VMware) d6b183eda4 tracing/kprobe: Remove unneeded extra strchr() from create_trace_kprobe()
By utilizing a temporary variable, we can avoid adding another call to
strchr(). Instead, save the first call to a temp variable, and then use that
variable as the reference to set the event variable.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-09-24 04:44:52 -04:00
Dennis Zhou (Facebook) c839e7a03f blkcg: remove bio->bi_css and instead use bio->bi_blkg
Prior patches ensured that all bios are now associated with some blkg.
This now makes bio->bi_css unnecessary as blkg maintains a reference to
the blkcg already.

This patch removes the field bi_css and transfers corresponding uses to
access via bi_blkg.

Signed-off-by: Dennis Zhou <dennisszhou@gmail.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-09-21 20:29:13 -06:00
Vaibhav Nagarnaik 83f365554e ring-buffer: Allow for rescheduling when removing pages
When reducing ring buffer size, pages are removed by scheduling a work
item on each CPU for the corresponding CPU ring buffer. After the pages
are removed from ring buffer linked list, the pages are free()d in a
tight loop. The loop does not give up CPU until all pages are removed.
In a worst case behavior, when lot of pages are to be freed, it can
cause system stall.

After the pages are removed from the list, the free() can happen while
the work is rescheduled. Call cond_resched() in the loop to prevent the
system hangup.

Link: http://lkml.kernel.org/r/20180907223129.71994-1-vnagarnaik@google.com

Cc: stable@vger.kernel.org
Fixes: 83f40318da ("ring-buffer: Make removal of ring buffer pages atomic")
Reported-by: Jason Behmer <jbehmer@google.com>
Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-09-17 18:15:11 -04:00
Linus Torvalds 452938cbd8 Masami found an off by one bug in the code that keeps "notrace" functions
from being traced by kprobes. During my testing, I found that there's places
 that we may want to add kprobes to notrace, thus we may end up changing this
 code before 4.19 is released. The history behind this change is that we
 found that adding kprobes to various notrace functions caused the kernel to
 crashed. We took the safe route and decided not to allow kprobes to trace
 any notrace function. But because notrace is added to functions that just
 cause weird side effects to the function tracer, but are still safe,
 preventing kprobes for all notrace functios may be too much of a big hammer.
 One such place is __schedule() is marked notrace, to keep function tracer
 from doing strange recursive loops when it gets traced with NEED_RESCHED
 set. With this change, one can not add kprobes to the scheduler.
 
 Masami also added code to use gcov on ftrace.
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Merge tag 'trace-v4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Masami found an off by one bug in the code that keeps "notrace"
  functions from being traced by kprobes. During my testing, I found
  that there's places that we may want to add kprobes to notrace, thus
  we may end up changing this code before 4.19 is released.

  The history behind this change is that we found that adding kprobes to
  various notrace functions caused the kernel to crashed. We took the
  safe route and decided not to allow kprobes to trace any notrace
  function.

  But because notrace is added to functions that just cause weird side
  effects to the function tracer, but are still safe, preventing kprobes
  for all notrace functios may be too much of a big hammer.

  One such place is __schedule() is marked notrace, to keep function
  tracer from doing strange recursive loops when it gets traced with
  NEED_RESCHED set. With this change, one can not add kprobes to the
  scheduler.

  Masami also added code to use gcov on ftrace"

* tag 'trace-v4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing/kprobes: Fix to check notrace function with correct range
  tracing: Allow gcov profiling on only ftrace subsystem
2018-08-23 13:07:00 -07:00
Linus Torvalds 5bed49adfe for-4.19/post-20180822
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Merge tag 'for-4.19/post-20180822' of git://git.kernel.dk/linux-block

Pull more block updates from Jens Axboe:

 - Set of bcache fixes and changes (Coly)

 - The flush warn fix (me)

 - Small series of BFQ fixes (Paolo)

 - wbt hang fix (Ming)

 - blktrace fix (Steven)

 - blk-mq hardware queue count update fix (Jianchao)

 - Various little fixes

* tag 'for-4.19/post-20180822' of git://git.kernel.dk/linux-block: (31 commits)
  block/DAC960.c: make some arrays static const, shrinks object size
  blk-mq: sync the update nr_hw_queues with blk_mq_queue_tag_busy_iter
  blk-mq: init hctx sched after update ctx and hctx mapping
  block: remove duplicate initialization
  tracing/blktrace: Fix to allow setting same value
  pktcdvd: fix setting of 'ret' error return for a few cases
  block: change return type to bool
  block, bfq: return nbytes and not zero from struct cftype .write() method
  block, bfq: improve code of bfq_bfqq_charge_time
  block, bfq: reduce write overcharge
  block, bfq: always update the budget of an entity when needed
  block, bfq: readd missing reset of parent-entity service
  blk-wbt: fix IO hang in wbt_wait()
  block: don't warn for flush on read-only device
  bcache: add the missing comments for smp_mb()/smp_wmb()
  bcache: remove unnecessary space before ioctl function pointer arguments
  bcache: add missing SPDX header
  bcache: move open brace at end of function definitions to next line
  bcache: add static const prefix to char * array declarations
  bcache: fix code comments style
  ...
2018-08-22 13:38:05 -07:00
Masami Hiramatsu 9161a864ff tracing/kprobes: Fix to check notrace function with correct range
Fix within_notrace_func() to check notrace function correctly.

Since the ftrace_location_range(start, end) function checks
the range inclusively (start <= ftrace-loc <= end), the end
address must not include the entry address of next function.

However, within_notrace_func() uses kallsyms_lookup_size_offset()
to get the function size and calculate the end address from
adding the size to the entry address. This means the end address
is the entry address of the next function.

In the result, within_notrace_func() fails to find notrace
function if the next function of the target function is
ftraced.

Let's subtract 1 from the end address so that ftrace_location_range()
can check it correctly.

Link: http://lkml.kernel.org/r/153485669706.16611.17726752296213785504.stgit@devbox

Fixes: commit 45408c4f92 ("tracing: kprobes: Prohibit probing on notrace function")
Reported-by: Michael Rodin <michael@rodin.online>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-21 09:41:12 -04:00
Masami Hiramatsu 6b7dca401c tracing: Allow gcov profiling on only ftrace subsystem
Add GCOV_PROFILE_FTRACE to allow gcov profiling on only files in ftrace
subsystem. This config option will be used for checking kselftest/ftrace
coverage.

Link: http://lkml.kernel.org/r/153483647755.32472.4746349899604275441.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-21 09:11:49 -04:00
Linus Torvalds 7140ad3898 Updates for v4.19:
- Restructure of lockdep and latency tracers
 
    This is the biggest change. Joel Fernandes restructured the hooks
    from irqs and preemption disabling and enabling. He got rid of
    a lot of the preprocessor #ifdef mess that they caused.
 
    He turned both lockdep and the latency tracers to use trace events
    inserted in the preempt/irqs disabling paths. But unfortunately,
    these started to cause issues in corner cases. Thus, parts of the
    code was reverted back to where lockde and the latency tracers
    just get called directly (without using the trace events).
    But because the original change cleaned up the code very nicely
    we kept that, as well as the trace events for preempt and irqs
    disabling, but they are limited to not being called in NMIs.
 
  - Have trace events use SRCU for "rcu idle" calls. This was required
    for the preempt/irqs off trace events. But it also had to not
    allow them to be called in NMI context. Waiting till Paul makes
    an NMI safe SRCU API.
 
  - New notrace SRCU API to allow trace events to use SRCU.
 
  - Addition of mcount-nop option support
 
  - SPDX headers replacing GPL templates.
 
  - Various other fixes and clean ups.
 
  - Some fixes are marked for stable, but were not fully tested
    before the merge window opened.
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Merge tag 'trace-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:

 - Restructure of lockdep and latency tracers

   This is the biggest change. Joel Fernandes restructured the hooks
   from irqs and preemption disabling and enabling. He got rid of a lot
   of the preprocessor #ifdef mess that they caused.

   He turned both lockdep and the latency tracers to use trace events
   inserted in the preempt/irqs disabling paths. But unfortunately,
   these started to cause issues in corner cases. Thus, parts of the
   code was reverted back to where lockdep and the latency tracers just
   get called directly (without using the trace events). But because the
   original change cleaned up the code very nicely we kept that, as well
   as the trace events for preempt and irqs disabling, but they are
   limited to not being called in NMIs.

 - Have trace events use SRCU for "rcu idle" calls. This was required
   for the preempt/irqs off trace events. But it also had to not allow
   them to be called in NMI context. Waiting till Paul makes an NMI safe
   SRCU API.

 - New notrace SRCU API to allow trace events to use SRCU.

 - Addition of mcount-nop option support

 - SPDX headers replacing GPL templates.

 - Various other fixes and clean ups.

 - Some fixes are marked for stable, but were not fully tested before
   the merge window opened.

* tag 'trace-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (44 commits)
  tracing: Fix SPDX format headers to use C++ style comments
  tracing: Add SPDX License format tags to tracing files
  tracing: Add SPDX License format to bpf_trace.c
  blktrace: Add SPDX License format header
  s390/ftrace: Add -mfentry and -mnop-mcount support
  tracing: Add -mcount-nop option support
  tracing: Avoid calling cc-option -mrecord-mcount for every Makefile
  tracing: Handle CC_FLAGS_FTRACE more accurately
  Uprobe: Additional argument arch_uprobe to uprobe_write_opcode()
  Uprobes: Simplify uprobe_register() body
  tracepoints: Free early tracepoints after RCU is initialized
  uprobes: Use synchronize_rcu() not synchronize_sched()
  tracing: Fix synchronizing to event changes with tracepoint_synchronize_unregister()
  ftrace: Remove unused pointer ftrace_swapper_pid
  tracing: More reverting of "tracing: Centralize preemptirq tracepoints and unify their usage"
  tracing/irqsoff: Handle preempt_count for different configs
  tracing: Partial revert of "tracing: Centralize preemptirq tracepoints and unify their usage"
  tracing: irqsoff: Account for additional preempt_disable
  trace: Use rcu_dereference_raw for hooks from trace-event subsystem
  tracing/kprobes: Fix within_notrace_func() to check only notrace functions
  ...
2018-08-20 18:32:00 -07:00
Steven Rostedt (VMware) bb730b5833 tracing: Fix SPDX format headers to use C++ style comments
The Linux kernel adopted the SPDX License format headers to ease license
compliance management, and uses the C++ '//' style comments for the SPDX
header tags. Some files in the tracing directory used the C style /* */
comments for them. To be consistent across all files, replace the /* */
C style SPDX tags with the C++ // SPDX tags.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-16 19:08:06 -04:00
Steven Rostedt (VMware) bcea3f96e1 tracing: Add SPDX License format tags to tracing files
Add the SPDX License header to ease license compliance management.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-16 19:08:06 -04:00
Steven Rostedt (VMware) 179a0cc4e0 tracing: Add SPDX License format to bpf_trace.c
Add the SPDX License header to ease license compliance management.

Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-16 19:07:36 -04:00
Steven Rostedt (VMware) 757d914007 tracing/blktrace: Fix to allow setting same value
Masami Hiramatsu reported:

  Current trace-enable attribute in sysfs returns an error
  if user writes the same setting value as current one,
  e.g.

    # cat /sys/block/sda/trace/enable
    0
    # echo 0 > /sys/block/sda/trace/enable
    bash: echo: write error: Invalid argument
    # echo 1 > /sys/block/sda/trace/enable
    # echo 1 > /sys/block/sda/trace/enable
    bash: echo: write error: Device or resource busy

  But this is not a preferred behavior, it should ignore
  if new setting is same as current one. This fixes the
  problem as below.

    # cat /sys/block/sda/trace/enable
    0
    # echo 0 > /sys/block/sda/trace/enable
    # echo 1 > /sys/block/sda/trace/enable
    # echo 1 > /sys/block/sda/trace/enable

Link: http://lkml.kernel.org/r/20180816103802.08678002@gandalf.local.home

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: stable@vger.kernel.org
Fixes: cd649b8bb8 ("blktrace: remove sysfs_blk_trace_enable_show/store()")
Reported-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-08-16 14:13:56 -06:00
Steven Rostedt (VMware) 91c1e6ba39 blktrace: Add SPDX License format header
Add the SPDX License header to ease license compliance management.

Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-16 15:49:02 -04:00
Vasily Gorbik 2f4df0017b tracing: Add -mcount-nop option support
-mcount-nop gcc option generates the calls to the profiling functions
as nops which allows to avoid patching mcount jump with NOP instructions
initially.

-mcount-nop gcc option will be activated if platform selects
HAVE_NOP_MCOUNT and gcc actually supports it.
In addition to that CC_USING_NOP_MCOUNT is defined and could be used by
architectures to adapt ftrace patching behavior.

Link: http://lkml.kernel.org/r/patch-3.thread-aa7b8d.git-e02ed2dc082b.your-ad-here.call-01533557518-ext-9465@work.hours

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-15 22:38:38 -04:00
Linus Torvalds b125d90388 Printk changes for 4.19
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Merge tag 'printk-for-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk

Pull printk updates from Petr Mladek:

 - Different vendors have a different expectation about a console
   quietness. Make it configurable to reduce bike-shedding about the
   upstream default

 - Decide about the message visibility when the message is stored. It
   avoids races caused by a delayed console handling

 - Always store printk() messages into the per-CPU buffers again in NMI.
   The only exception is when flushing trace log in panic(). There the
   risk of loosing messages is worth an eventual reordering

 - Handle invalid %pO printf modifiers correctly

 - Better handle %p printf modifier tests before crng is initialized

 - Some clean up

* tag 'printk-for-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
  lib/vsprintf: Do not handle %pO[^F] as %px
  printk: Fix warning about unused suppress_message_printing
  printk/nmi: Prevent deadlock when accessing the main log buffer in NMI
  printk: Create helper function to queue deferred console handling
  printk: Split the code for storing a message into the log buffer
  printk: Clean up syslog_print_all()
  printk: Remove unnecessary kmalloc() from syslog during clear
  printk: Make CONSOLE_LOGLEVEL_QUIET configurable
  printk: make sure to print log on console.
  lib/test_printf.c: accept "ptrval" as valid result for plain 'p' tests
2018-08-15 11:18:53 -07:00
Linus Torvalds e6ecec342f This was a moderately busy cycle for docs, with the usual collection of
small fixes and updates.  We also have new ktime_get_*() docs from Arnd,
 some kernel-doc fixes, a new set of Italian translations (non so se vale la
 pena, ma non fa male - speriamo bene), and some extensive early
 memory-management documentation improvements from Mike Rapoport.
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Merge tag 'docs-4.19' of git://git.lwn.net/linux

Pull documentation update from Jonathan Corbet:
 "This was a moderately busy cycle for docs, with the usual collection
  of small fixes and updates.

  We also have new ktime_get_*() docs from Arnd, some kernel-doc fixes,
  a new set of Italian translations (non so se vale la pena, ma non fa
  male - speriamo bene), and some extensive early memory-management
  documentation improvements from Mike Rapoport"

* tag 'docs-4.19' of git://git.lwn.net/linux: (52 commits)
  Documentation: corrections to console/console.txt
  Documentation: add ioctl number entry for v4l2-subdev.h
  Remove gendered language from management style documentation
  scripts/kernel-doc: Escape all literal braces in regexes
  docs/mm: add description of boot time memory management
  docs/mm: memblock: add overview documentation
  docs/mm: memblock: add kernel-doc description for memblock types
  docs/mm: memblock: add kernel-doc comments for memblock_add[_node]
  docs/mm: memblock: update kernel-doc comments
  mm/memblock: add a name for memblock flags enumeration
  docs/mm: bootmem: add overview documentation
  docs/mm: bootmem: add kernel-doc description of 'struct bootmem_data'
  docs/mm: bootmem: fix kernel-doc warnings
  docs/mm: nobootmem: fixup kernel-doc comments
  mm/bootmem: drop duplicated kernel-doc comments
  Documentation: vm.txt: Adding 'nr_hugepages_mempolicy' parameter description.
  doc:it_IT: translation for kernel-hacking
  docs: Fix the reference labels in Locking.rst
  doc: tracing: Fix a typo of trace_stat
  mm: Introduce new type vm_fault_t
  ...
2018-08-14 14:29:31 -07:00
Linus Torvalds 73ba2fb33c for-4.19/block-20180812
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Merge tag 'for-4.19/block-20180812' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
 "First pull request for this merge window, there will also be a
  followup request with some stragglers.

  This pull request contains:

   - Fix for a thundering heard issue in the wbt block code (Anchal
     Agarwal)

   - A few NVMe pull requests:
      * Improved tracepoints (Keith)
      * Larger inline data support for RDMA (Steve Wise)
      * RDMA setup/teardown fixes (Sagi)
      * Effects log suppor for NVMe target (Chaitanya Kulkarni)
      * Buffered IO suppor for NVMe target (Chaitanya Kulkarni)
      * TP4004 (ANA) support (Christoph)
      * Various NVMe fixes

   - Block io-latency controller support. Much needed support for
     properly containing block devices. (Josef)

   - Series improving how we handle sense information on the stack
     (Kees)

   - Lightnvm fixes and updates/improvements (Mathias/Javier et al)

   - Zoned device support for null_blk (Matias)

   - AIX partition fixes (Mauricio Faria de Oliveira)

   - DIF checksum code made generic (Max Gurtovoy)

   - Add support for discard in iostats (Michael Callahan / Tejun)

   - Set of updates for BFQ (Paolo)

   - Removal of async write support for bsg (Christoph)

   - Bio page dirtying and clone fixups (Christoph)

   - Set of bcache fix/changes (via Coly)

   - Series improving blk-mq queue setup/teardown speed (Ming)

   - Series improving merging performance on blk-mq (Ming)

   - Lots of other fixes and cleanups from a slew of folks"

* tag 'for-4.19/block-20180812' of git://git.kernel.dk/linux-block: (190 commits)
  blkcg: Make blkg_root_lookup() work for queues in bypass mode
  bcache: fix error setting writeback_rate through sysfs interface
  null_blk: add lock drop/acquire annotation
  Blk-throttle: reduce tail io latency when iops limit is enforced
  block: paride: pd: mark expected switch fall-throughs
  block: Ensure that a request queue is dissociated from the cgroup controller
  block: Introduce blk_exit_queue()
  blkcg: Introduce blkg_root_lookup()
  block: Remove two superfluous #include directives
  blk-mq: count the hctx as active before allocating tag
  block: bvec_nr_vecs() returns value for wrong slab
  bcache: trivial - remove tailing backslash in macro BTREE_FLAG
  bcache: make the pr_err statement used for ENOENT only in sysfs_attatch section
  bcache: set max writeback rate when I/O request is idle
  bcache: add code comments for bset.c
  bcache: fix mistaken comments in request.c
  bcache: fix mistaken code comments in bcache.h
  bcache: add a comment in super.c
  bcache: avoid unncessary cache prefetch bch_btree_node_get()
  bcache: display rate debug parameters to 0 when writeback is not running
  ...
2018-08-14 10:23:25 -07:00
Steven Rostedt (VMware) 016f8ffc48 uprobes: Use synchronize_rcu() not synchronize_sched()
While debugging another bug, I was looking at all the synchronize*()
functions being used in kernel/trace, and noticed that trace_uprobes was
using synchronize_sched(), with a comment to synchronize with
{u,ret}_probe_trace_func(). When looking at those functions, the data is
protected with "rcu_read_lock()" and not with "rcu_read_lock_sched()". This
is using the wrong synchronize_*() function.

Link: http://lkml.kernel.org/r/20180809160553.469e1e32@gandalf.local.home

Cc: stable@vger.kernel.org
Fixes: 70ed91c6ec ("tracing/uprobes: Support ftrace_event_file base multibuffer")
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-10 15:32:28 -04:00
Steven Rostedt (VMware) e0a568dcd1 tracing: Fix synchronizing to event changes with tracepoint_synchronize_unregister()
Now that some trace events can be protected by srcu_read_lock(tracepoint_srcu),
we need to make sure all locations that depend on this are also protected.
There were many places that did a synchronize_sched() thinking that it was
enough to protect againts access to trace events. This use to be the case,
but now that we use SRCU for _rcuidle() trace events, they may not be
protected by synchronize_sched(), as they may be called in paths that RCU is
not watching for preempt disable.

Fixes: e6753f23d9 ("tracepoint: Make rcuidle tracepoint callers use SRCU")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-10 15:12:01 -04:00
Colin Ian King b207de3ec5 ftrace: Remove unused pointer ftrace_swapper_pid
Pointer ftrace_swapper_pid is defined but is never used hence it is
redundant and can be removed. The use of this variable was removed
in commit 345ddcc882 ("ftrace: Have set_ftrace_pid use the bitmap
like events do").

Cleans up clang warning:
warning: 'ftrace_swapper_pid' defined but not used [-Wunused-const-variable=]

Link: http://lkml.kernel.org/r/20180809125609.13142-1-colin.king@canonical.com

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-10 15:12:01 -04:00
Steven Rostedt (VMware) 3f1756dc21 tracing: More reverting of "tracing: Centralize preemptirq tracepoints and unify their usage"
Joel Fernandes created a nice patch that cleaned up the duplicate hooks used
by lockdep and irqsoff latency tracer. It made both use tracepoints. But the
latency tracer is triggering warnings when using tracepoints to call into
the latency tracer's routines. Mainly, they can be called from NMI context.
If that happens, then the SRCU may not work properly because on some
architectures, SRCU is not safe to be called in both NMI and non-NMI
context.

This is a partial revert of the clean up patch c3bc8fd637 ("tracing:
Centralize preemptirq tracepoints and unify their usage") that adds back the
direct calls into the latency tracer. It also only calls the trace events
when not in NMI.

Link: http://lkml.kernel.org/r/20180809210654.622445925@goodmis.org
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Fixes: c3bc8fd637 ("tracing: Centralize preemptirq tracepoints and unify their usage")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-10 15:12:00 -04:00
Steven Rostedt (VMware) f27107fa20 tracing/irqsoff: Handle preempt_count for different configs
I was hitting the following warning:

WARNING: CPU: 0 PID: 1 at kernel/trace/trace_irqsoff.c:631 tracer_hardirqs_off+0x15/0x2a

Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.18.0-rc6-test+ #13
Hardware name: MSI MS-7823/CSM-H87M-G43 (MS-7823), BIOS V1.6 02/22/2014
EIP: tracer_hardirqs_off+0x15/0x2a
Code: ff 85 c0 74 0e 8b 45 00 8b 50 04 8b 45 04 e8 35 ff ff ff 5d c3 55 64 a1 cc 37 51 c1 a9 ff ff ff 7f 89 e5 53 89 d3 89 ca 75 02 <0f> 0b e8 90 fc ff ff 85 c0 74 07 89 d8 e8 0c ff ff ff 5b 5d c3 55
EAX: 80000000 EBX: c04337f0 ECX: c04338e3 EDX: c04338e3
ESI: c04337f0 EDI: c04338e3 EBP: f2aa1d68 ESP: f2aa1d64
DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00210046
CR0: 80050033 CR2: 00000000 CR3: 01668000 CR4: 001406f0
Call Trace:
 trace_irq_disable_rcuidle+0x63/0x6c
 trace_hardirqs_off+0x26/0x30
 default_send_IPI_mask_allbutself_logical+0x31/0x93
 default_send_IPI_allbutself+0x37/0x48
 native_send_call_func_ipi+0x4d/0x6a
 smp_call_function_many+0x165/0x19d
 ? add_nops+0x34/0x34
 ? trace_hardirqs_on_caller+0x2d/0x2d
 ? add_nops+0x34/0x34
 smp_call_function+0x1f/0x23
 on_each_cpu+0x15/0x43
 ? trace_hardirqs_on_caller+0x2d/0x2d
 ? trace_hardirqs_on_caller+0x2d/0x2d
 ? trace_irq_disable_rcuidle+0x1/0x6c
 text_poke_bp+0xa0/0xc2
 ? trace_hardirqs_on_caller+0x2d/0x2d
 arch_jump_label_transform+0xa7/0xcb
 ? trace_irq_disable_rcuidle+0x5/0x6c
 __jump_label_update+0x3e/0x6d
 jump_label_update+0x7d/0x81
 static_key_slow_inc_cpuslocked+0x58/0x6d
 static_key_slow_inc+0x19/0x20
 tracepoint_probe_register_prio+0x19e/0x1d1
 ? start_critical_timings+0x1c/0x1c
 tracepoint_probe_register+0xf/0x11
 irqsoff_tracer_init+0x21/0xf2
 tracer_init+0x16/0x1a
 trace_selftest_startup_irqsoff+0x25/0xc4
 run_tracer_selftest+0xca/0x131
 register_tracer+0xd5/0x172
 ? trace_event_define_fields_preemptirq_template+0x45/0x45
 init_irqsoff_tracer+0xd/0x11
 do_one_initcall+0xab/0x1e8
 ? rcu_read_lock_sched_held+0x3d/0x44
 ? trace_initcall_level+0x52/0x86
 kernel_init_freeable+0x195/0x21a
 ? rest_init+0xb4/0xb4
 kernel_init+0xd/0xe4
 ret_from_fork+0x2e/0x38

It is due to running a CONFIG_PREEMPT_VOLUNTARY kernel, which would trigger
this warning every time:

	WARN_ON_ONCE(preempt_count());

Because on CONFIG_PREEMPT_VOLUNTARY, preempt_count() is always zero.

This warning is to make sure preempt_count is set because
tracer_hardirqs_on() does a preempt_enable_notrace() to make the
preempt_trace() work properly, as being called by a trace event, the trace
event code disables preemption, and the tracer wants to know what the
preemption was before it was called.

Instead of enabling preemption like this, just record the preempt_count,
subtract PREEMPT_DISABLE_OFFSET from it (which is zero with !CONFIG_PREEMPT
set), and pass that value to the necessary functions, which should use the
passed in parameter instead of calling preempt_count() directly.

Fixes: da5b3ebb45 ("tracing: irqsoff: Account for additional preempt_disable")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-10 15:12:00 -04:00
Steven Rostedt (VMware) bff1b208a5 tracing: Partial revert of "tracing: Centralize preemptirq tracepoints and unify their usage"
Joel Fernandes created a nice patch that cleaned up the duplicate hooks used
by lockdep and irqsoff latency tracer. It made both use tracepoints. But it
caused lockdep to trigger several false positives. We have not figured out
why yet, but removing lockdep from using the trace event hooks and just call
its helper functions directly (like it use to), makes the problem go away.

This is a partial revert of the clean up patch c3bc8fd637 ("tracing:
Centralize preemptirq tracepoints and unify their usage") that adds direct
calls for lockdep, but also keeps most of the clean up done to get rid of
the horrible preprocessor if statements.

Link: http://lkml.kernel.org/r/20180806155058.5ee875f4@gandalf.local.home

Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Fixes: c3bc8fd637 ("tracing: Centralize preemptirq tracepoints and unify their usage")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-10 15:11:25 -04:00
Joel Fernandes (Google) da5b3ebb45 tracing: irqsoff: Account for additional preempt_disable
Recently we tried to make the preemptirqsoff tracer to use irqsoff
tracepoint probes. However this causes issues as reported by Masami:

[2.271078] Testing tracer preemptirqsoff: .. no entries found ..FAILED!
[2.381015] WARNING: CPU: 0 PID: 1 at /home/mhiramat/ksrc/linux/kernel/
trace/trace.c:1512 run_tracer_selftest+0xf3/0x154

This is due to the tracepoint code increasing the preempt nesting count
by calling an additional preempt_disable before calling into the
preemptoff tracer which messes up the preempt_count() check in
tracer_hardirqs_off.

To fix this, make the irqsoff tracer probes balance the additional outer
preempt_disable with a preempt_enable_notrace.

The other way to fix this is to just use SRCU for all tracepoints.
However we can't do that because we can't use NMIs from RCU context.

Link: http://lkml.kernel.org/r/20180806034049.67949-1-joel@joelfernandes.org

Fixes: c3bc8fd637 ("tracing: Centralize preemptirq tracepoints and unify their usage")
Fixes: e6753f23d9 ("tracepoint: Make rcuidle tracepoint callers use SRCU")
Reported-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-06 21:55:24 -04:00
Jens Axboe 05b9ba4b55 Linux 4.18-rc6
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Merge tag 'v4.18-rc6' into for-4.19/block2

Pull in 4.18-rc6 to get the NVMe core AEN change to avoid a
merge conflict down the line.

Signed-of-by: Jens Axboe <axboe@kernel.dk>
2018-08-05 19:32:09 -06:00
Joel Fernandes (Google) da25a672cf trace: Use rcu_dereference_raw for hooks from trace-event subsystem
Since we switched to using SRCU for tracepoints used in the idle path,
we can no longer use rcu_dereference_sched for dereferencing points in
trace-event hooks.

Since tracepoints can now use either SRCU or sched-RCU, just use
rcu_dereference_raw for traceevents just like we're doing when
dereferencing the tracepoint table.

This prevents an RCU warning reported by Masami:

[  282.060593] WARNING: can't dereference registers at 00000000f3c7f62b
[  282.063200] =============================
[  282.064082] WARNING: suspicious RCU usage
[  282.064963] 4.18.0-rc6+ #15 Tainted: G        W
[  282.066048] -----------------------------
[  282.066923] /home/mhiramat/ksrc/linux/kernel/trace/trace_events.c:242
				suspicious rcu_dereference_check() usage!
[  282.068974]
[  282.068974] other info that might help us debug this:
[  282.068974]
[  282.070770]
[  282.070770] RCU used illegally from idle CPU!
[  282.070770] rcu_scheduler_active = 2, debug_locks = 1
[  282.072938] RCU used illegally from extended quiescent state!
[  282.074183] no locks held by swapper/0/0.
[  282.075071]
[  282.075071] stack backtrace:
[  282.076121] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G        W
[  282.077782] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
[  282.079604] Call Trace:
[  282.080212]  <IRQ>
[  282.080755]  dump_stack+0x85/0xcb
[  282.081523]  trace_event_ignore_this_pid+0x66/0x70
[  282.082541]  trace_event_raw_event_preemptirq_template+0xa2/0xb0
[  282.083774]  ? interrupt_entry+0xc4/0xe0
[  282.084665]  ? trace_hardirqs_off_thunk+0x1a/0x1c
[  282.085669]  trace_hardirqs_off_caller+0x90/0xd0
[  282.086597]  trace_hardirqs_off_thunk+0x1a/0x1c
[  282.087433]  ? call_function_interrupt+0xa/0x20
[  282.088201]  interrupt_entry+0xc4/0xe0
[  282.088848]  ? call_function_interrupt+0xa/0x20
[  282.089579]  </IRQ>
[  282.090029]  ? native_safe_halt+0x2/0x10
[  282.090695]  ? default_idle+0x1f/0x160
[  282.091330]  ? default_idle_call+0x24/0x40
[  282.091997]  ? do_idle+0x210/0x250
[  282.092658]  ? cpu_startup_entry+0x6f/0x80
[  282.093338]  ? start_kernel+0x49d/0x4bd
[  282.093987]  ? secondary_startup_64+0xa5/0xb0

Link: http://lkml.kernel.org/r/20180803023407.225852-1-joel@joelfernandes.org

Reported-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: e6753f23d9 ("tracepoint: Make rcuidle tracepoint callers use SRCU")
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-03 09:38:39 -04:00
Masami Hiramatsu 6bc6c77cfc tracing/kprobes: Fix within_notrace_func() to check only notrace functions
Fix within_notrace_func() to check only notrace functions and to ignore the
kprobe-event which can not solve symbol addresses.

within_notrace_func() returns true if the given kprobe events probe point
seems to be out-of-range. But that is not the correct place to check for it,
it should be done in kprobes afterwards.

kprobe-events allow users to define a probe point on "currently unloaded
module" so that it can trace the event during module load. In this case, the
user will put a probe on a symbol which is not in kallsyms yet and it hits
the within_notrace_func().  As a result, kprobe-events always refuses if
user defines a probe on a "currenly unloaded module".

Fixes: commit 45408c4f92 ("tracing: kprobes: Prohibit probing on notrace function")
Link: http://lkml.kernel.org/r/153319624799.29007.13604430345640129926.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-02 12:34:41 -04:00
Ingo Molnar 16e0e6a83b Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-08-02 09:59:20 +02:00
Gustavo A. R. Silva 44ec3ec01f ftrace: Use true and false for boolean values in ops_references_rec()
Return statements in functions returning bool should use true or false
instead of an integer value.

This code was detected with the help of Coccinelle.

Link: http://lkml.kernel.org/r/20180802010056.GA31012@embeddedor.com

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-01 21:15:31 -04:00
Steven Rostedt (VMware) d7224c0e12 ring-buffer: Make ring_buffer_record_is_set_on() return bool
The value of ring_buffer_record_is_set_on() is either true or false, so have
its return value be bool.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-01 21:09:50 -04:00
Steven Rostedt (VMware) 3ebea280d7 ring-buffer: Make ring_buffer_record_is_on() return bool
The value of ring_buffer_record_is_on() is either true or false, so have its
return value be bool.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-01 21:08:30 -04:00
Steven Rostedt (VMware) ec57350883 tracing: Make tracer_tracing_is_on() return bool
There's code that expects tracer_tracing_is_on() to be either true or false,
not some random number. Currently, it should only return one or zero, but
just in case, change its return value to bool, to enforce it.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-01 16:08:57 -04:00
Steven Rostedt (VMware) 978defee11 tracing: Do a WARN_ON() if start_thread() in hwlat is called when thread exists
The start function of the hwlat tracer should never be called when the hwlat
thread already exists. If it is called, do a WARN_ON().

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-01 16:06:02 -04:00
Erica Bugden 82fbc8c48a ftrace: Add missing check for existing hwlat thread
The hwlat tracer uses a kernel thread to measure latencies. The function
that creates this kernel thread, start_kthread(), can be called when the
tracer is initialized and when the tracer is explicitly enabled.
start_kthread() does not check if there is an existing hwlat kernel
thread and will create a new one each time it is called.

This causes the reference to the previous thread to be lost. Without the
thread reference, the old kernel thread becomes unstoppable and
continues to use CPU time even after the hwlat tracer has been disabled.
This problem can be observed when a system is booted with tracing
enabled and the hwlat tracer is configured like this:

	echo hwlat > current_tracer; echo 1 > tracing_on

Add the missing check for an existing kernel thread in start_kthread()
to prevent this problem. This function and the rest of the hwlat kernel
thread setup and teardown are already serialized because they are called
through the tracer core code with trace_type_lock held.

[
 Note, this only fixes the symptom. The real fix was not to call
 this function when tracing_on was already one. But this still makes
 the code more robust, so we'll add it.
]

Link: http://lkml.kernel.org/r/1533120354-22923-1-git-send-email-erica.bugden@linutronix.de

Signed-off-by: Erica Bugden <erica.bugden@linutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-01 16:04:24 -04:00
Steven Rostedt (VMware) f143641bfe tracing: Do not call start/stop() functions when tracing_on does not change
Currently, when one echo's in 1 into tracing_on, the current tracer's
"start()" function is executed, even if tracing_on was already one. This can
lead to strange side effects. One being that if the hwlat tracer is enabled,
and someone does "echo 1 > tracing_on" into tracing_on, the hwlat tracer's
start() function is called again which will recreate another kernel thread,
and make it unable to remove the old one.

Link: http://lkml.kernel.org/r/1533120354-22923-1-git-send-email-erica.bugden@linutronix.de

Cc: stable@vger.kernel.org
Fixes: 2df8f8a6a8 ("tracing: Fix regression with irqsoff tracer and tracing_on file")
Reported-by: Erica Bugden <erica.bugden@linutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-01 16:01:02 -04:00
Joel Fernandes (Google) c3bc8fd637 tracing: Centralize preemptirq tracepoints and unify their usage
This patch detaches the preemptirq tracepoints from the tracers and
keeps it separate.

Advantages:
* Lockdep and irqsoff event can now run in parallel since they no longer
have their own calls.

* This unifies the usecase of adding hooks to an irqsoff and irqson
event, and a preemptoff and preempton event.
  3 users of the events exist:
  - Lockdep
  - irqsoff and preemptoff tracers
  - irqs and preempt trace events

The unification cleans up several ifdefs and makes the code in preempt
tracer and irqsoff tracers simpler. It gets rid of all the horrific
ifdeferry around PROVE_LOCKING and makes configuration of the different
users of the tracepoints more easy and understandable. It also gets rid
of the time_* function calls from the lockdep hooks used to call into
the preemptirq tracer which is not needed anymore. The negative delta in
lines of code in this patch is quite large too.

In the patch we introduce a new CONFIG option PREEMPTIRQ_TRACEPOINTS
as a single point for registering probes onto the tracepoints. With
this,
the web of config options for preempt/irq toggle tracepoints and its
users becomes:

 PREEMPT_TRACER   PREEMPTIRQ_EVENTS  IRQSOFF_TRACER PROVE_LOCKING
       |                 |     \         |           |
       \    (selects)    /      \        \ (selects) /
      TRACE_PREEMPT_TOGGLE       ----> TRACE_IRQFLAGS
                      \                  /
                       \ (depends on)   /
                     PREEMPTIRQ_TRACEPOINTS

Other than the performance tests mentioned in the previous patch, I also
ran the locking API test suite. I verified that all tests cases are
passing.

I also injected issues by not registering lockdep probes onto the
tracepoints and I see failures to confirm that the probes are indeed
working.

This series + lockdep probes not registered (just to inject errors):
[    0.000000]      hard-irqs-on + irq-safe-A/21:  ok  |  ok  |  ok  |
[    0.000000]      soft-irqs-on + irq-safe-A/21:  ok  |  ok  |  ok  |
[    0.000000]        sirq-safe-A => hirqs-on/12:FAILED|FAILED|  ok  |
[    0.000000]        sirq-safe-A => hirqs-on/21:FAILED|FAILED|  ok  |
[    0.000000]          hard-safe-A + irqs-on/12:FAILED|FAILED|  ok  |
[    0.000000]          soft-safe-A + irqs-on/12:FAILED|FAILED|  ok  |
[    0.000000]          hard-safe-A + irqs-on/21:FAILED|FAILED|  ok  |
[    0.000000]          soft-safe-A + irqs-on/21:FAILED|FAILED|  ok  |
[    0.000000]     hard-safe-A + unsafe-B #1/123:  ok  |  ok  |  ok  |
[    0.000000]     soft-safe-A + unsafe-B #1/123:  ok  |  ok  |  ok  |

With this series + lockdep probes registered, all locking tests pass:

[    0.000000]      hard-irqs-on + irq-safe-A/21:  ok  |  ok  |  ok  |
[    0.000000]      soft-irqs-on + irq-safe-A/21:  ok  |  ok  |  ok  |
[    0.000000]        sirq-safe-A => hirqs-on/12:  ok  |  ok  |  ok  |
[    0.000000]        sirq-safe-A => hirqs-on/21:  ok  |  ok  |  ok  |
[    0.000000]          hard-safe-A + irqs-on/12:  ok  |  ok  |  ok  |
[    0.000000]          soft-safe-A + irqs-on/12:  ok  |  ok  |  ok  |
[    0.000000]          hard-safe-A + irqs-on/21:  ok  |  ok  |  ok  |
[    0.000000]          soft-safe-A + irqs-on/21:  ok  |  ok  |  ok  |
[    0.000000]     hard-safe-A + unsafe-B #1/123:  ok  |  ok  |  ok  |
[    0.000000]     soft-safe-A + unsafe-B #1/123:  ok  |  ok  |  ok  |

Link: http://lkml.kernel.org/r/20180730222423.196630-4-joel@joelfernandes.org

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-31 11:32:27 -04:00
Francis Deslauriers d899926f55 selftest/ftrace: Move kprobe selftest function to separate compile unit
Move selftest function to its own compile unit so it can be compiled
with the ftrace cflags (CC_FLAGS_FTRACE) allowing it to be probed
during the ftrace startup tests.

Link: http://lkml.kernel.org/r/153294604271.32740.16490677128630177030.stgit@devbox

Signed-off-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-30 18:41:04 -04:00
Masami Hiramatsu 45408c4f92 tracing: kprobes: Prohibit probing on notrace function
Prohibit kprobe-events probing on notrace functions.  Since probing on a
notrace function can cause a recursive event call. In most cases those are just
skipped, but in some cases it falls into an infinite recursive call.

This protection can be disabled by the kconfig
CONFIG_KPROBE_EVENTS_ON_NOTRACE=y, but it is highly recommended to keep it
"n" for normal kernel builds.  Note that this is only available if "kprobes on
ftrace" has been implemented on the target arch and CONFIG_KPROBES_ON_FTRACE=y.

Link: http://lkml.kernel.org/r/153294601436.32740.10557881188933661239.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Francis Deslauriers <francis.deslauriers@efficios.com>
[ Slight grammar and spelling fixes ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-30 18:28:52 -04:00
kbuild test robot 518eeca05c tracing: preemptirq_delay_run() can be static
Automatically found by kbuild test robot.

Fixes: ffdc73a3b2ad ("lib: Add module for testing preemptoff/irqsoff latency tracers")
Signed-off-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-27 17:58:34 -04:00
Steven Rostedt (VMware) 87107a25a2 tracing/kprobes: Simplify the logic of enable_trace_kprobe()
The function enable_trace_kprobe() performs slightly differently if the file
parameter is passed in as NULL on non-NULL. Instead of checking file twice,
move the code between the two tests into a static inline helper function to
make the code easier to follow.

Link: http://lkml.kernel.org/r/20180725224728.7b1d5db2@vmware.local.home
Link: http://lkml.kernel.org/r/20180726121152.4dd54330@gandalf.local.home

Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-27 09:36:20 -04:00
Masami Hiramatsu 1fee4f7752 doc: tracing: Fix a typo of trace_stat
The name of the directory for per-cpu function statistics
is trace_stat, not trace_stats.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-07-26 15:48:10 -06:00
Masami Hiramatsu 72809cbf67 tracing: Remove orphaned function ftrace_nr_registered_ops()
Remove ftrace_nr_registered_ops() because it is no longer used.

ftrace_nr_registered_ops() has been introduced by commit ea701f11da
("ftrace: Add selftest to test function trace recursion protection"), but
its caller has been removed by commit 05cbbf643b ("tracing: Fix selftest
function recursion accounting"). So it is not called anymore.

Link: http://lkml.kernel.org/r/153260907227.12474.5234899025934963683.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-26 10:58:43 -04:00
Masami Hiramatsu 7b144b6c79 tracing: Remove orphaned function using_ftrace_ops_list_func().
Remove using_ftrace_ops_list_func() since it is no longer used.

Using ftrace_ops_list_func() has been introduced by commit 7eea4fce02
("tracing/stack_trace: Skip 4 instead of 3 when using ftrace_ops_list_func")
as a helper function, but its caller has been removed by commit 72ac426a5b
("tracing: Clean up stack tracing and fix fentry updates").  So it is not
called anymore.

Link: http://lkml.kernel.org/r/153260904427.12474.9952096317439329851.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-26 10:53:05 -04:00
Steven Rostedt (VMware) f6b7425cfb tracing: Make unregister_trigger() static
Nothing uses unregister_trigger() outside of trace_events_trigger.c file,
thus it should be static. Not sure why this was ever converted, because
its counter part, register_trigger(), was always static.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-26 10:50:18 -04:00
Joel Fernandes (Google) f96e8577da lib: Add module for testing preemptoff/irqsoff latency tracers
Here we introduce a test module for introducing a long preempt or irq
disable delay in the kernel which the preemptoff or irqsoff tracers can
detect. This module is to be used only for test purposes and is default
disabled.

Following is the expected output (only briefly shown) that can be parsed
to verify that the tracers are working correctly. We will use this from
the kselftests in future patches.

For the preemptoff tracer:

echo preemptoff > /d/tracing/current_tracer
sleep 1
insmod ./preemptirq_delay_test.ko test_mode=preempt delay=500000
sleep 1
bash-4.3# cat /d/tracing/trace
preempt -1066    2...2    0us@: preemptirq_delay_run <-preemptirq_delay_run
preempt -1066    2...2 500002us : preemptirq_delay_run <-preemptirq_delay_run
preempt -1066    2...2 500004us : tracer_preempt_on <-preemptirq_delay_run
preempt -1066    2...2 500012us : <stack trace>
 => kthread
 => ret_from_fork

For the irqsoff tracer:

echo irqsoff > /d/tracing/current_tracer
sleep 1
insmod ./preemptirq_delay_test.ko test_mode=irq delay=500000
sleep 1
bash-4.3# cat /d/tracing/trace
irq dis -1069    1d..1    0us@: preemptirq_delay_run
irq dis -1069    1d..1 500001us : preemptirq_delay_run
irq dis -1069    1d..1 500002us : tracer_hardirqs_on <-preemptirq_delay_run
irq dis -1069    1d..1 500005us : <stack trace>
 => ret_from_fork

Link: http://lkml.kernel.org/r/20180712213611.GA8743@joelaf.mtv.corp.google.com

Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Julia Cartwright <julia@ni.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Glexiner <tglx@linutronix.de>
Cc: Todd Kjos <tkjos@google.com>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[ Erick is a co-developer of this commit ]
Signed-off-by: Erick Reyes <erickreyes@google.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-26 10:50:17 -04:00
Joel Fernandes (Google) 2b27ece6c5 tracing/irqsoff: Split reset into separate functions
Split reset functions into seperate functions in preparation
of future patches that need to do tracer specific reset.

Link: http://lkml.kernel.org/r/20180628182149.226164-4-joel@joelfernandes.org

Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-26 10:50:17 -04:00
Steven Rostedt (VMware) 2519c1bbe3 tracing: Quiet gcc warning about maybe unused link variable
Commit 57ea2a34ad ("tracing/kprobes: Fix trace_probe flags on
enable_trace_kprobe() failure") added an if statement that depends on another
if statement that gcc doesn't see will initialize the "link" variable and
gives the warning:

 "warning: 'link' may be used uninitialized in this function"

It is really a false positive, but to quiet the warning, and also to make
sure that it never actually is used uninitialized, initialize the "link"
variable to NULL and add an if (!WARN_ON_ONCE(!link)) where the compiler
thinks it could be used uninitialized.

Cc: stable@vger.kernel.org
Fixes: 57ea2a34ad ("tracing/kprobes: Fix trace_probe flags on enable_trace_kprobe() failure")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-25 22:33:50 -04:00
Steven Rostedt (VMware) 15cc78644d tracing: Fix possible double free in event_enable_trigger_func()
There was a case that triggered a double free in event_trigger_callback()
due to the called reg() function freeing the trigger_data and then it
getting freed again by the error return by the caller. The solution there
was to up the trigger_data ref count.

Code inspection found that event_enable_trigger_func() has the same issue,
but is not as easy to trigger (requires harder to trigger failures). It
needs to be solved slightly different as it needs more to clean up when the
reg() function fails.

Link: http://lkml.kernel.org/r/20180725124008.7008e586@gandalf.local.home

Cc: stable@vger.kernel.org
Fixes: 7862ad1846 ("tracing: Add 'enable_event' and 'disable_event' event trigger commands")
Reivewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-25 21:25:16 -04:00
Artem Savkov 57ea2a34ad tracing/kprobes: Fix trace_probe flags on enable_trace_kprobe() failure
If enable_trace_kprobe fails to enable the probe in enable_k(ret)probe
it returns an error, but does not unset the tp flags it set previously.
This results in a probe being considered enabled and failures like being
unable to remove the probe through kprobe_events file since probes_open()
expects every probe to be disabled.

Link: http://lkml.kernel.org/r/20180725102826.8300-1-asavkov@redhat.com
Link: http://lkml.kernel.org/r/20180725142038.4765-1-asavkov@redhat.com

Cc: Ingo Molnar <mingo@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 41a7dd420c ("tracing/kprobes: Support ftrace_event_file base multibuffer")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-25 11:41:08 -04:00
Masami Hiramatsu 73c8d89455 ring_buffer: tracing: Inherit the tracing setting to next ring buffer
Maintain the tracing on/off setting of the ring_buffer when switching
to the trace buffer snapshot.

Taking a snapshot is done by swapping the backup ring buffer
(max_tr_buffer). But since the tracing on/off setting is defined
by the ring buffer, when swapping it, the tracing on/off setting
can also be changed. This causes a strange result like below:

  /sys/kernel/debug/tracing # cat tracing_on
  1
  /sys/kernel/debug/tracing # echo 0 > tracing_on
  /sys/kernel/debug/tracing # cat tracing_on
  0
  /sys/kernel/debug/tracing # echo 1 > snapshot
  /sys/kernel/debug/tracing # cat tracing_on
  1
  /sys/kernel/debug/tracing # echo 1 > snapshot
  /sys/kernel/debug/tracing # cat tracing_on
  0

We don't touch tracing_on, but snapshot changes tracing_on
setting each time. This is an anomaly, because user doesn't know
that each "ring_buffer" stores its own tracing-enable state and
the snapshot is done by swapping ring buffers.

Link: http://lkml.kernel.org/r/153149929558.11274.11730609978254724394.stgit@devbox

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Hiraku Toyooka <hiraku.toyooka@cybertrust.co.jp>
Cc: stable@vger.kernel.org
Fixes: debdd57f51 ("tracing: Make a snapshot feature available from userspace")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
[ Updated commit log and comment in the code ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-25 10:29:41 -04:00
Steven Rostedt (VMware) 1863c38725 tracing: Fix double free of event_trigger_data
Running the following:

 # cd /sys/kernel/debug/tracing
 # echo 500000 > buffer_size_kb
[ Or some other number that takes up most of memory ]
 # echo snapshot > events/sched/sched_switch/trigger

Triggers the following bug:

 ------------[ cut here ]------------
 kernel BUG at mm/slub.c:296!
 invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC PTI
 CPU: 6 PID: 6878 Comm: bash Not tainted 4.18.0-rc6-test+ #1066
 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016
 RIP: 0010:kfree+0x16c/0x180
 Code: 05 41 0f b6 72 51 5b 5d 41 5c 4c 89 d7 e9 ac b3 f8 ff 48 89 d9 48 89 da 41 b8 01 00 00 00 5b 5d 41 5c 4c 89 d6 e9 f4 f3 ff ff <0f> 0b 0f 0b 48 8b 3d d9 d8 f9 00 e9 c1 fe ff ff 0f 1f 40 00 0f 1f
 RSP: 0018:ffffb654436d3d88 EFLAGS: 00010246
 RAX: ffff91a9d50f3d80 RBX: ffff91a9d50f3d80 RCX: ffff91a9d50f3d80
 RDX: 00000000000006a4 RSI: ffff91a9de5a60e0 RDI: ffff91a9d9803500
 RBP: ffffffff8d267c80 R08: 00000000000260e0 R09: ffffffff8c1a56be
 R10: fffff0d404543cc0 R11: 0000000000000389 R12: ffffffff8c1a56be
 R13: ffff91a9d9930e18 R14: ffff91a98c0c2890 R15: ffffffff8d267d00
 FS:  00007f363ea64700(0000) GS:ffff91a9de580000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 000055c1cacc8e10 CR3: 00000000d9b46003 CR4: 00000000001606e0
 Call Trace:
  event_trigger_callback+0xee/0x1d0
  event_trigger_write+0xfc/0x1a0
  __vfs_write+0x33/0x190
  ? handle_mm_fault+0x115/0x230
  ? _cond_resched+0x16/0x40
  vfs_write+0xb0/0x190
  ksys_write+0x52/0xc0
  do_syscall_64+0x5a/0x160
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
 RIP: 0033:0x7f363e16ab50
 Code: 73 01 c3 48 8b 0d 38 83 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 79 db 2c 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e e3 01 00 48 89 04 24
 RSP: 002b:00007fff9a4c6378 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
 RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 00007f363e16ab50
 RDX: 0000000000000009 RSI: 000055c1cacc8e10 RDI: 0000000000000001
 RBP: 000055c1cacc8e10 R08: 00007f363e435740 R09: 00007f363ea64700
 R10: 0000000000000073 R11: 0000000000000246 R12: 0000000000000009
 R13: 0000000000000001 R14: 00007f363e4345e0 R15: 00007f363e4303c0
 Modules linked in: ip6table_filter ip6_tables snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_seq snd_seq_device i915 snd_pcm snd_timer i2c_i801 snd soundcore i2c_algo_bit drm_kms_helper
86_pkg_temp_thermal video kvm_intel kvm irqbypass wmi e1000e
 ---[ end trace d301afa879ddfa25 ]---

The cause is because the register_snapshot_trigger() call failed to
allocate the snapshot buffer, and then called unregister_trigger()
which freed the data that was passed to it. Then on return to the
function that called register_snapshot_trigger(), as it sees it
failed to register, it frees the trigger_data again and causes
a double free.

By calling event_trigger_init() on the trigger_data (which only ups
the reference counter for it), and then event_trigger_free() afterward,
the trigger_data would not get freed by the registering trigger function
as it would only up and lower the ref count for it. If the register
trigger function fails, then the event_trigger_free() called after it
will free the trigger data normally.

Link: http://lkml.kernel.org/r/20180724191331.738eb819@gandalf.local.home

Cc: stable@vger.kerne.org
Fixes: 93e31ffbf4 ("tracing: Add 'snapshot' event trigger command")
Reported-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-25 10:29:24 -04:00
Ingo Molnar 93081caaae Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25 11:47:02 +02:00
Joel Fernandes (Google) f8494fa3dd tracing: Reorder display of TGID to be after PID
Currently ftrace displays data in trace output like so:

                                       _-----=> irqs-off
                                      / _----=> need-resched
                                     | / _---=> hardirq/softirq
                                     || / _--=> preempt-depth
                                     ||| /     delay
            TASK-PID   CPU    TGID   ||||    TIMESTAMP  FUNCTION
               | |       |      |    ||||       |         |
            bash-1091  [000] ( 1091) d..2    28.313544: sched_switch:

However Android's trace visualization tools expect a slightly different
format due to an out-of-tree patch patch that was been carried for a
decade, notice that the TGID and CPU fields are reversed:

                                       _-----=> irqs-off
                                      / _----=> need-resched
                                     | / _---=> hardirq/softirq
                                     || / _--=> preempt-depth
                                     ||| /     delay
            TASK-PID    TGID   CPU   ||||    TIMESTAMP  FUNCTION
               | |        |      |   ||||       |         |
            bash-1091  ( 1091) [002] d..2    64.965177: sched_switch:

From kernel v4.13 onwards, during which TGID was introduced, tracing
with systrace on all Android kernels will break (most Android kernels
have been on 4.9 with Android patches, so this issues hasn't been seen
yet). From v4.13 onwards things will break.

The chrome browser's tracing tools also embed the systrace viewer which
uses the legacy TGID format and updates to that are known to be
difficult to make.

Considering this, I suggest we make this change to the upstream kernel
and backport it to all Android kernels. I believe this feature is merged
recently enough into the upstream kernel that it shouldn't be a problem.
Also logically, IMO it makes more sense to group the TGID with the
TASK-PID and the CPU after these.

Link: http://lkml.kernel.org/r/20180626000822.113931-1-joel@joelfernandes.org

Cc: jreck@google.com
Cc: tkjos@google.com
Cc: stable@vger.kernel.org
Fixes: 441dae8f2f ("tracing: Add support for display of tgid in trace output")
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-12 19:56:25 -04:00
Jiri Olsa 0fc8c3581d tracing/kprobe: Release kprobe print_fmt properly
We don't release tk->tp.call.print_fmt when destroying
local uprobe. Also there's missing print_fmt kfree in
create_local_trace_kprobe error path.

Link: http://lkml.kernel.org/r/20180709141906.2390-1-jolsa@kernel.org

Cc: stable@vger.kernel.org
Fixes: e12f03d703 ("perf/core: Implement the 'perf_kprobe' PMU")
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-11 15:50:52 -04:00
Liu Bo e1a413245a Blktrace: bail out early if block debugfs is not configured
Since @blk_debugfs_root couldn't be configured dynamically, we can
save a few memory allocation if it's not there.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-09 09:07:52 -06:00
Petr Mladek 03fc7f9c99 printk/nmi: Prevent deadlock when accessing the main log buffer in NMI
The commit 719f6a7040 ("printk: Use the main logbuf in NMI
when logbuf_lock is available") brought back the possible deadlocks
in printk() and NMI.

The check of logbuf_lock is done only in printk_nmi_enter() to prevent
mixed output. But another CPU might take the lock later, enter NMI, and:

      + Both NMIs might be serialized by yet another lock, for example,
	the one in nmi_cpu_backtrace().

      + The other CPU might get stopped in NMI, see smp_send_stop()
	in panic().

The only safe solution is to use trylock when storing the message
into the main log-buffer. It might cause reordering when some lines
go to the main lock buffer directly and others are delayed via
the per-CPU buffer. It means that it is not useful in general.

This patch replaces the problematic NMI deferred context with NMI
direct context. It can be used to mark a code that might produce
many messages in NMI and the risk of losing them is more critical
than problems with eventual reordering.

The context is then used when dumping trace buffers on oops. It was
the primary motivation for the original fix. Also the reordering is
even smaller issue there because some traces have their own time stamps.

Finally, nmi_cpu_backtrace() need not longer be serialized because
it will always us the per-CPU buffers again.

Fixes: 719f6a7040 ("printk: Use the main logbuf in NMI when logbuf_lock is available")
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20180627142028.11259-1-pmladek@suse.com
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-07-09 14:10:40 +02:00
Changbin Du 1fe4293f4b tracing: Fix missing return symbol in function_graph output
The function_graph tracer does not show the interrupt return marker for the
leaf entry. On leaf entries, we see an unbalanced interrupt marker (the
interrupt was entered, but nevern left).

Before:
 1)               |  SyS_write() {
 1)               |    __fdget_pos() {
 1)   0.061 us    |      __fget_light();
 1)   0.289 us    |    }
 1)               |    vfs_write() {
 1)   0.049 us    |      rw_verify_area();
 1) + 15.424 us   |      __vfs_write();
 1)   ==========> |
 1)   6.003 us    |      smp_apic_timer_interrupt();
 1)   0.055 us    |      __fsnotify_parent();
 1)   0.073 us    |      fsnotify();
 1) + 23.665 us   |    }
 1) + 24.501 us   |  }

After:
 0)               |  SyS_write() {
 0)               |    __fdget_pos() {
 0)   0.052 us    |      __fget_light();
 0)   0.328 us    |    }
 0)               |    vfs_write() {
 0)   0.057 us    |      rw_verify_area();
 0)               |      __vfs_write() {
 0)   ==========> |
 0)   8.548 us    |      smp_apic_timer_interrupt();
 0)   <========== |
 0) + 36.507 us   |      } /* __vfs_write */
 0)   0.049 us    |      __fsnotify_parent();
 0)   0.066 us    |      fsnotify();
 0) + 50.064 us   |    }
 0) + 50.952 us   |  }

Link: http://lkml.kernel.org/r/1517413729-20411-1-git-send-email-changbin.du@intel.com

Cc: stable@vger.kernel.org
Fixes: f8b755ac8e ("tracing/function-graph-tracer: Output arrows signal on hardirq call/return")
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-03 18:47:11 -04:00
Yisheng Xie 5ccba64a56 ftrace: Nuke clear_ftrace_function
clear_ftrace_function is not used outside of ftrace.c and is not help to
use a function, so nuke it per Steve's suggestion.

Link: http://lkml.kernel.org/r/1517537689-34947-1-git-send-email-xieyisheng1@huawei.com

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-03 18:33:19 -04:00
Mathieu Malaterre 26b68dd2f4 tracing: Use __printf markup to silence compiler
Silence warnings (triggered at W=1) by adding relevant __printf attributes.

  CC      kernel/trace/trace.o
kernel/trace/trace.c: In function ‘__trace_array_vprintk’:
kernel/trace/trace.c:2979:2: warning: function might be possible candidate for ‘gnu_printf’ format attribute [-Wsuggest-attribute=format]
  len = vscnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args);
  ^~~
  AR      kernel/trace/built-in.o

Link: http://lkml.kernel.org/r/20180308205843.27447-1-malat@debian.org

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-03 18:32:04 -04:00
yuan linyu f26808ba72 tracing: Optimize trace_buffer_iter() logic
Simplify and optimize the logic in trace_buffer_iter() to use a conditional
operation instead of an if conditional.

Link: http://lkml.kernel.org/r/20180408113631.3947-1-cugyly@163.com

Signed-off-by: yuan linyu <Linyu.Yuan@alcatel-sbell.com.cn>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-03 18:23:33 -04:00
Steven Rostedt (VMware) f90658725b tracing: Make create_filter() code match the comments
The comment in create_filter() states that the passed in filter pointer
(filterp) will either be NULL or contain an error message stating why the
filter failed. But it also expects the filter pointer to point to NULL when
passed in. If it is not, the function create_filter_start() will warn and
return an error message without updating the filter pointer. This is not
what the comment states.

As we always expect the pointer to point to NULL, if it is not, trigger a
WARN_ON(), set it to NULL, and then continue the path as the rest will work
as the comment states. Also update the comment to state it must point to
NULL.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-03 18:14:40 -04:00
Arnd Bergmann cf4d418e65 tracing: Avoid string overflow
'err' is used as a NUL-terminated string, but using strncpy() with the length
equal to the buffer size may result in lack of the termination:

kernel/trace/trace_events_hist.c: In function 'hist_err_event':
kernel/trace/trace_events_hist.c:396:3: error: 'strncpy' specified bound 256 equals destination size [-Werror=stringop-truncation]
   strncpy(err, var, MAX_FILTER_STR_VAL);

This changes it to use the safer strscpy() instead.

Link: http://lkml.kernel.org/r/20180328140920.2842153-1-arnd@arndb.de

Cc: stable@vger.kernel.org
Fixes: f404da6e1d ("tracing: Add 'last error' error facility for hist triggers")
Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-03 18:14:39 -04:00
Mauro Carvalho Chehab ea272257cc docs: histogram.txt: convert it to ReST file format
Despite being mentioned at Documentation/trace/ftrace.rst as a
rst file, this file was still a text one, with several issues.

Convert it to ReST and add it to the trace index:
- Mark the document title as such;
- Identify and indent the literal blocks;
- Use the proper markups for table.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-07-02 11:26:02 -06:00
Ingo Molnar f446474889 Merge branch 'linus' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-26 09:02:41 +02:00
Gustavo A. R. Silva 08ae88f810 tracing: Use swap macro in update_max_tr
Make use of the swap macro and remove unnecessary variable _buf_.
This makes the code easier to read and maintain. Also, reduces the
stack usage.

This code was detected with the help of Coccinelle.

Link: http://lkml.kernel.org/r/20180209175316.GA18720@embeddedgus

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-06-21 15:12:43 -04:00
Steven Rostedt (VMware) 70303420b5 tracing: Check for no filter when processing event filters
The syzkaller detected a out-of-bounds issue with the events filter code,
specifically here:

	prog[N].pred = NULL;					/* #13 */
	prog[N].target = 1;		/* TRUE */
	prog[N+1].pred = NULL;
	prog[N+1].target = 0;		/* FALSE */
->	prog[N-1].target = N;
	prog[N-1].when_to_branch = false;

As that's the first reference to a "N-1" index, it appears that the code got
here with N = 0, which means the filter parser found no filter to parse
(which shouldn't ever happen, but apparently it did).

Add a new error to the parsing code that will check to make sure that N is
not zero before going into this part of the code. If N = 0, then -EINVAL is
returned, and a error message is added to the filter.

Cc: stable@vger.kernel.org
Fixes: 80765597bc ("tracing: Rewrite filter logic to be simpler and faster")
Reported-by: air icy <icytxw@gmail.com>
bugzilla url: https://bugzilla.kernel.org/show_bug.cgi?id=200019
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-06-21 15:12:42 -04:00
Masami Hiramatsu cce188bd58 bpf/error-inject/kprobes: Clear current_kprobe and enable preempt in kprobe
Clear current_kprobe and enable preemption in kprobe
even if pre_handler returns !0.

This simplifies function override using kprobes.

Jprobe used to require to keep the preemption disabled and
keep current_kprobe until it returned to original function
entry. For this reason kprobe_int3_handler() and similar
arch dependent kprobe handers checks pre_handler result
and exit without enabling preemption if the result is !0.

After removing the jprobe, Kprobes does not need to
keep preempt disabled even if user handler returns !0
anymore.

But since the function override handler in error-inject
and bpf is also returns !0 if it overrides a function,
to balancing the preempt count, it enables preemption
and reset current kprobe by itself.

That is a bad design that is very buggy. This fixes
such unbalanced preempt-count and current_kprobes setting
in kprobes, bpf and error-inject.

Note: for powerpc and x86, this removes all preempt_disable
from kprobe_ftrace_handler because ftrace callbacks are
called under preempt disabled.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: linux-snps-arc@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: sparclinux@vger.kernel.org
Link: https://lore.kernel.org/lkml/152942494574.15209.12323837825873032258.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-21 12:33:19 +02:00
Mauro Carvalho Chehab 5fb94e9ca3 docs: Fix some broken references
As we move stuff around, some doc references are broken. Fix some of
them via this script:
	./scripts/documentation-file-ref-check --fix

Manually checked if the produced result is valid, removing a few
false-positives.

Acked-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Coly Li <colyli@suse.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>
2018-06-15 18:10:01 -03:00
Kees Cook 42bc47b353 treewide: Use array_size() in vmalloc()
The vmalloc() function has no 2-factor argument form, so multiplication
factors need to be wrapped in array_size(). This patch replaces cases of:

        vmalloc(a * b)

with:
        vmalloc(array_size(a, b))

as well as handling cases of:

        vmalloc(a * b * c)

with:

        vmalloc(array3_size(a, b, c))

This does, however, attempt to ignore constant size factors like:

        vmalloc(4 * 1024)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  vmalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  vmalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  vmalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
  vmalloc(
-	sizeof(TYPE) * (COUNT_ID)
+	array_size(COUNT_ID, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(TYPE) * COUNT_ID
+	array_size(COUNT_ID, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(TYPE) * (COUNT_CONST)
+	array_size(COUNT_CONST, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(TYPE) * COUNT_CONST
+	array_size(COUNT_CONST, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(THING) * (COUNT_ID)
+	array_size(COUNT_ID, sizeof(THING))
  , ...)
|
  vmalloc(
-	sizeof(THING) * COUNT_ID
+	array_size(COUNT_ID, sizeof(THING))
  , ...)
|
  vmalloc(
-	sizeof(THING) * (COUNT_CONST)
+	array_size(COUNT_CONST, sizeof(THING))
  , ...)
|
  vmalloc(
-	sizeof(THING) * COUNT_CONST
+	array_size(COUNT_CONST, sizeof(THING))
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

  vmalloc(
-	SIZE * COUNT
+	array_size(COUNT, SIZE)
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  vmalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  vmalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  vmalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  vmalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  vmalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  vmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  vmalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  vmalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  vmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  vmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  vmalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  vmalloc(C1 * C2 * C3, ...)
|
  vmalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants.
@@
expression E1, E2;
constant C1, C2;
@@

(
  vmalloc(C1 * C2, ...)
|
  vmalloc(
-	E1 * E2
+	array_size(E1, E2)
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Kees Cook 6396bb2215 treewide: kzalloc() -> kcalloc()
The kzalloc() function has a 2-factor argument form, kcalloc(). This
patch replaces cases of:

        kzalloc(a * b, gfp)

with:
        kcalloc(a * b, gfp)

as well as handling cases of:

        kzalloc(a * b * c, gfp)

with:

        kzalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kzalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kzalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kzalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kzalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kzalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kzalloc
+ kcalloc
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kzalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kzalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kzalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kzalloc(sizeof(THING) * C2, ...)
|
  kzalloc(sizeof(TYPE) * C2, ...)
|
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(C1 * C2, ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Kees Cook 6da2ec5605 treewide: kmalloc() -> kmalloc_array()
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This
patch replaces cases of:

        kmalloc(a * b, gfp)

with:
        kmalloc_array(a * b, gfp)

as well as handling cases of:

        kmalloc(a * b * c, gfp)

with:

        kmalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kmalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kmalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The tools/ directory was manually excluded, since it has its own
implementation of kmalloc().

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kmalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kmalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kmalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kmalloc
+ kmalloc_array
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kmalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kmalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kmalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kmalloc(sizeof(THING) * C2, ...)
|
  kmalloc(sizeof(TYPE) * C2, ...)
|
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(C1 * C2, ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Linus Torvalds c90fca951e powerpc updates for 4.18
Notable changes:
 
  - Support for split PMD page table lock on 64-bit Book3S (Power8/9).
 
  - Add support for HAVE_RELIABLE_STACKTRACE, so we properly support live
    patching again.
 
  - Add support for patching barrier_nospec in copy_from_user() and syscall entry.
 
  - A couple of fixes for our data breakpoints on Book3S.
 
  - A series from Nick optimising TLB/mm handling with the Radix MMU.
 
  - Numerous small cleanups to squash sparse/gcc warnings from Mathieu Malaterre.
 
  - Several series optimising various parts of the 32-bit code from Christophe Leroy.
 
  - Removal of support for two old machines, "SBC834xE" and "C2K" ("GEFanuc,C2K"),
    which is why the diffstat has so many deletions.
 
 And many other small improvements & fixes.
 
 There's a few out-of-area changes. Some minor ftrace changes OK'ed by Steve, and
 a fix to our powernv cpuidle driver. Then there's a series touching mm, x86 and
 fs/proc/task_mmu.c, which cleans up some details around pkey support. It was
 ack'ed/reviewed by Ingo & Dave and has been in next for several weeks.
 
 Thanks to:
   Akshay Adiga, Alastair D'Silva, Alexey Kardashevskiy, Al Viro, Andrew
   Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Arnd Bergmann, Balbir Singh,
   Cédric Le Goater, Christophe Leroy, Christophe Lombard, Colin Ian King, Dave
   Hansen, Fabio Estevam, Finn Thain, Frederic Barrat, Gautham R. Shenoy, Haren
   Myneni, Hari Bathini, Ingo Molnar, Jonathan Neuschäfer, Josh Poimboeuf,
   Kamalesh Babulal, Madhavan Srinivasan, Mahesh Salgaonkar, Mark Greer, Mathieu
   Malaterre, Matthew Wilcox, Michael Neuling, Michal Suchanek, Naveen N. Rao,
   Nicholas Piggin, Nicolai Stange, Olof Johansson, Paul Gortmaker, Paul
   Mackerras, Peter Rosin, Pridhiviraj Paidipeddi, Ram Pai, Rashmica Gupta, Ravi
   Bangoria, Russell Currey, Sam Bobroff, Samuel Mendoza-Jonas, Segher
   Boessenkool, Shilpasri G Bhat, Simon Guo, Souptick Joarder, Stewart Smith,
   Thiago Jung Bauermann, Torsten Duwe, Vaibhav Jain, Wei Yongjun, Wolfram Sang,
   Yisheng Xie, YueHaibing.
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Merge tag 'powerpc-4.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Notable changes:

   - Support for split PMD page table lock on 64-bit Book3S (Power8/9).

   - Add support for HAVE_RELIABLE_STACKTRACE, so we properly support
     live patching again.

   - Add support for patching barrier_nospec in copy_from_user() and
     syscall entry.

   - A couple of fixes for our data breakpoints on Book3S.

   - A series from Nick optimising TLB/mm handling with the Radix MMU.

   - Numerous small cleanups to squash sparse/gcc warnings from Mathieu
     Malaterre.

   - Several series optimising various parts of the 32-bit code from
     Christophe Leroy.

   - Removal of support for two old machines, "SBC834xE" and "C2K"
     ("GEFanuc,C2K"), which is why the diffstat has so many deletions.

  And many other small improvements & fixes.

  There's a few out-of-area changes. Some minor ftrace changes OK'ed by
  Steve, and a fix to our powernv cpuidle driver. Then there's a series
  touching mm, x86 and fs/proc/task_mmu.c, which cleans up some details
  around pkey support. It was ack'ed/reviewed by Ingo & Dave and has
  been in next for several weeks.

  Thanks to: Akshay Adiga, Alastair D'Silva, Alexey Kardashevskiy, Al
  Viro, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Arnd
  Bergmann, Balbir Singh, Cédric Le Goater, Christophe Leroy, Christophe
  Lombard, Colin Ian King, Dave Hansen, Fabio Estevam, Finn Thain,
  Frederic Barrat, Gautham R. Shenoy, Haren Myneni, Hari Bathini, Ingo
  Molnar, Jonathan Neuschäfer, Josh Poimboeuf, Kamalesh Babulal,
  Madhavan Srinivasan, Mahesh Salgaonkar, Mark Greer, Mathieu Malaterre,
  Matthew Wilcox, Michael Neuling, Michal Suchanek, Naveen N. Rao,
  Nicholas Piggin, Nicolai Stange, Olof Johansson, Paul Gortmaker, Paul
  Mackerras, Peter Rosin, Pridhiviraj Paidipeddi, Ram Pai, Rashmica
  Gupta, Ravi Bangoria, Russell Currey, Sam Bobroff, Samuel
  Mendoza-Jonas, Segher Boessenkool, Shilpasri G Bhat, Simon Guo,
  Souptick Joarder, Stewart Smith, Thiago Jung Bauermann, Torsten Duwe,
  Vaibhav Jain, Wei Yongjun, Wolfram Sang, Yisheng Xie, YueHaibing"

* tag 'powerpc-4.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (251 commits)
  powerpc/64s/radix: Fix missing ptesync in flush_cache_vmap
  cpuidle: powernv: Fix promotion from snooze if next state disabled
  powerpc: fix build failure by disabling attribute-alias warning in pci_32
  ocxl: Fix missing unlock on error in afu_ioctl_enable_p9_wait()
  powerpc-opal: fix spelling mistake "Uniterrupted" -> "Uninterrupted"
  powerpc: fix spelling mistake: "Usupported" -> "Unsupported"
  powerpc/pkeys: Detach execute_only key on !PROT_EXEC
  powerpc/powernv: copy/paste - Mask SO bit in CR
  powerpc: Remove core support for Marvell mv64x60 hostbridges
  powerpc/boot: Remove core support for Marvell mv64x60 hostbridges
  powerpc/boot: Remove support for Marvell mv64x60 i2c controller
  powerpc/boot: Remove support for Marvell MPSC serial controller
  powerpc/embedded6xx: Remove C2K board support
  powerpc/lib: optimise PPC32 memcmp
  powerpc/lib: optimise 32 bits __clear_user()
  powerpc/time: inline arch_vtime_task_switch()
  powerpc/Makefile: set -mcpu=860 flag for the 8xx
  powerpc: Implement csum_ipv6_magic in assembly
  powerpc/32: Optimise __csum_partial()
  powerpc/lib: Adjust .balign inside string functions for PPC32
  ...
2018-06-07 10:23:33 -07:00
Linus Torvalds 1c8c5a9d38 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) Add Maglev hashing scheduler to IPVS, from Inju Song.

 2) Lots of new TC subsystem tests from Roman Mashak.

 3) Add TCP zero copy receive and fix delayed acks and autotuning with
    SO_RCVLOWAT, from Eric Dumazet.

 4) Add XDP_REDIRECT support to mlx5 driver, from Jesper Dangaard
    Brouer.

 5) Add ttl inherit support to vxlan, from Hangbin Liu.

 6) Properly separate ipv6 routes into their logically independant
    components. fib6_info for the routing table, and fib6_nh for sets of
    nexthops, which thus can be shared. From David Ahern.

 7) Add bpf_xdp_adjust_tail helper, which can be used to generate ICMP
    messages from XDP programs. From Nikita V. Shirokov.

 8) Lots of long overdue cleanups to the r8169 driver, from Heiner
    Kallweit.

 9) Add BTF ("BPF Type Format"), from Martin KaFai Lau.

10) Add traffic condition monitoring to iwlwifi, from Luca Coelho.

11) Plumb extack down into fib_rules, from Roopa Prabhu.

12) Add Flower classifier offload support to igb, from Vinicius Costa
    Gomes.

13) Add UDP GSO support, from Willem de Bruijn.

14) Add documentation for eBPF helpers, from Quentin Monnet.

15) Add TLS tx offload to mlx5, from Ilya Lesokhin.

16) Allow applications to be given the number of bytes available to read
    on a socket via a control message returned from recvmsg(), from
    Soheil Hassas Yeganeh.

17) Add x86_32 eBPF JIT compiler, from Wang YanQing.

18) Add AF_XDP sockets, with zerocopy support infrastructure as well.
    From Björn Töpel.

19) Remove indirect load support from all of the BPF JITs and handle
    these operations in the verifier by translating them into native BPF
    instead. From Daniel Borkmann.

20) Add GRO support to ipv6 gre tunnels, from Eran Ben Elisha.

21) Allow XDP programs to do lookups in the main kernel routing tables
    for forwarding. From David Ahern.

22) Allow drivers to store hardware state into an ELF section of kernel
    dump vmcore files, and use it in cxgb4. From Rahul Lakkireddy.

23) Various RACK and loss detection improvements in TCP, from Yuchung
    Cheng.

24) Add TCP SACK compression, from Eric Dumazet.

25) Add User Mode Helper support and basic bpfilter infrastructure, from
    Alexei Starovoitov.

26) Support ports and protocol values in RTM_GETROUTE, from Roopa
    Prabhu.

27) Support bulking in ->ndo_xdp_xmit() API, from Jesper Dangaard
    Brouer.

28) Add lots of forwarding selftests, from Petr Machata.

29) Add generic network device failover driver, from Sridhar Samudrala.

* ra.kernel.org:/pub/scm/linux/kernel/git/davem/net-next: (1959 commits)
  strparser: Add __strp_unpause and use it in ktls.
  rxrpc: Fix terminal retransmission connection ID to include the channel
  net: hns3: Optimize PF CMDQ interrupt switching process
  net: hns3: Fix for VF mailbox receiving unknown message
  net: hns3: Fix for VF mailbox cannot receiving PF response
  bnx2x: use the right constant
  Revert "net: sched: cls: Fix offloading when ingress dev is vxlan"
  net: dsa: b53: Fix for brcm tag issue in Cygnus SoC
  enic: fix UDP rss bits
  netdev-FAQ: clarify DaveM's position for stable backports
  rtnetlink: validate attributes in do_setlink()
  mlxsw: Add extack messages for port_{un, }split failures
  netdevsim: Add extack error message for devlink reload
  devlink: Add extack to reload and port_{un, }split operations
  net: metrics: add proper netlink validation
  ipmr: fix error path when ipmr_new_table fails
  ip6mr: only set ip6mr_table from setsockopt when ip6mr_new_table succeeds
  net: hns3: remove unused hclgevf_cfg_func_mta_filter
  netfilter: provide udp*_lib_lookup for nf_tproxy
  qed*: Utilize FW 8.37.2.0
  ...
2018-06-06 18:39:49 -07:00
Linus Torvalds 5eb6eed7e0 One new feature was added to ftrace, which is the trace_marker now supports
triggers. For example:
 
   # cd /sys/kernel/debug/tracing
   # echo 'snapshot' > events/ftrace/print/trigger
   # echo 'cause snapshot' > trace_marker
 
 The rest of the changes are various clean ups and also one stable fix that
 was added late in the cycle.
 -----BEGIN PGP SIGNATURE-----
 
 iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCWxftjBQccm9zdGVkdEBn
 b29kbWlzLm9yZwAKCRAp5XQQmuv6qosyAQCgmhb+/HgRYIbsKa8Q70E2pMx5A/za
 4rQ37Q9PhDUJlAD/aWXfrqcMm+buAU0yY4K+eb+f2feKXWXxdZ/fuh7+nA4=
 =lpXM
 -----END PGP SIGNATURE-----

Merge tag 'trace-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "One new feature was added to ftrace, which is the trace_marker now
  supports triggers. For example:

    # cd /sys/kernel/debug/tracing
    # echo 'snapshot' > events/ftrace/print/trigger
    # echo 'cause snapshot' > trace_marker

  The rest of the changes are various clean ups and also one stable fix
  that was added late in the cycle"

* tag 'trace-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (21 commits)
  tracing: Use match_string() instead of open coding it in trace_set_options()
  branch-check: fix long->int truncation when profiling branches
  ring-buffer: Fix typo in comment
  ring-buffer: Fix a bunch of typos in comments
  tracing/selftest: Add test to test simple snapshot trigger for trace_marker
  tracing/selftest: Add test to test hist trigger between kernel event and trace_marker
  tracing/selftest: Add selftests to test trace_marker histogram triggers
  ftrace/selftest: Fix reset_trigger() to handle triggers with filters
  ftrace/selftest: Have the reset_trigger code be a bit more careful
  tracing: Document trace_marker triggers
  tracing: Allow histogram triggers to access ftrace internal events
  tracing: Prevent further users of zero size static arrays in trace events
  tracing: Have zero size length in filter logic be full string
  tracing: Add trigger file for trace_markers tracefs/ftrace/print
  tracing: Do not show filter file for ftrace internal events
  tracing: Add brackets in ftrace event dynamic arrays
  tracing: Have event_trace_init() called by trace_init_tracefs()
  tracing: Add __find_event_file() to find event files without restrictions
  tracing: Do not reference event data in post call triggers
  tracepoints: Fix the descriptions of tracepoint_probe_register{_prio}
  ...
2018-06-06 16:39:18 -07:00
Yisheng Xie 591a033dc1 tracing: Use match_string() instead of open coding it in trace_set_options()
match_string() returns the index of an array for a matching string,
which can be used to simplify the code.

Link: http://lkml.kernel.org/r/1526546163-4609-1-git-send-email-xieyisheng1@huawei.com

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-06-05 16:19:39 -04:00
David S. Miller fd129f8941 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2018-06-05

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Add a new BPF hook for sendmsg similar to existing hooks for bind and
   connect: "This allows to override source IP (including the case when it's
   set via cmsg(3)) and destination IP:port for unconnected UDP (slow path).
   TCP and connected UDP (fast path) are not affected. This makes UDP support
   complete, that is, connected UDP is handled by connect hooks, unconnected
   by sendmsg ones.", from Andrey.

2) Rework of the AF_XDP API to allow extending it in future for type writer
   model if necessary. In this mode a memory window is passed to hardware
   and multiple frames might be filled into that window instead of just one
   that is the case in the current fixed frame-size model. With the new
   changes made this can be supported without having to add a new descriptor
   format. Also, core bits for the zero-copy support for AF_XDP have been
   merged as agreed upon, where i40e bits will be routed via Jeff later on.
   Various improvements to documentation and sample programs included as
   well, all from Björn and Magnus.

3) Given BPF's flexibility, a new program type has been added to implement
   infrared decoders. Quote: "The kernel IR decoders support the most
   widely used IR protocols, but there are many protocols which are not
   supported. [...] There is a 'long tail' of unsupported IR protocols,
   for which lircd is need to decode the IR. IR encoding is done in such
   a way that some simple circuit can decode it; therefore, BPF is ideal.
   [...] user-space can define a decoder in BPF, attach it to the rc
   device through the lirc chardev.", from Sean.

4) Several improvements and fixes to BPF core, among others, dumping map
   and prog IDs into fdinfo which is a straight forward way to correlate
   BPF objects used by applications, removing an indirect call and therefore
   retpoline in all map lookup/update/delete calls by invoking the callback
   directly for 64 bit archs, adding a new bpf_skb_cgroup_id() BPF helper
   for tc BPF programs to have an efficient way of looking up cgroup v2 id
   for policy or other use cases. Fixes to make sure we zero tunnel/xfrm
   state that hasn't been filled, to allow context access wrt pt_regs in
   32 bit archs for tracing, and last but not least various test cases
   for fixes that landed in bpf earlier, from Daniel.

5) Get rid of the ndo_xdp_flush API and extend the ndo_xdp_xmit with
   a XDP_XMIT_FLUSH flag instead which allows to avoid one indirect
   call as flushing is now merged directly into ndo_xdp_xmit(), from Jesper.

6) Add a new bpf_get_current_cgroup_id() helper that can be used in
   tracing to retrieve the cgroup id from the current process in order
   to allow for e.g. aggregation of container-level events, from Yonghong.

7) Two follow-up fixes for BTF to reject invalid input values and
   related to that also two test cases for BPF kselftests, from Martin.

8) Various API improvements to the bpf_fib_lookup() helper, that is,
   dropping MPLS bits which are not fully hashed out yet, rejecting
   invalid helper flags, returning error for unsupported address
   families as well as renaming flowlabel to flowinfo, from David.

9) Various fixes and improvements to sockmap BPF kselftests in particular
   in proper error detection and data verification, from Prashant.

10) Two arm32 BPF JIT improvements. One is to fix imm range check with
    regards to whether immediate fits into 24 bits, and a naming cleanup
    to get functions related to rsh handling consistent to those handling
    lsh, from Wang.

11) Two compile warning fixes in BPF, one for BTF and a false positive
    to silent gcc in stack_map_get_build_id_offset(), from Arnd.

12) Add missing seg6.h header into tools include infrastructure in order
    to fix compilation of BPF kselftests, from Mathieu.

13) Several formatting cleanups in the BPF UAPI helper description that
    also fix an error during rst2man compilation, from Quentin.

14) Hide an unused variable in sk_msg_convert_ctx_access() when IPv6 is
    not built into the kernel, from Yue.

15) Remove a useless double assignment in dev_map_enqueue(), from Colin.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-05 12:42:19 -04:00
Linus Torvalds 4057adafb3 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:

 - updates to the handling of expedited grace periods

 - updates to reduce lock contention in the rcu_node combining tree

   [ These are in preparation for the consolidation of RCU-bh,
     RCU-preempt, and RCU-sched into a single flavor, which was
     requested by Linus in response to a security flaw whose root cause
     included confusion between the multiple flavors of RCU ]

 - torture-test updates that save their users some time and effort

 - miscellaneous fixes

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits)
  rcu/x86: Provide early rcu_cpu_starting() callback
  torture: Make kvm-find-errors.sh find build warnings
  rcutorture: Abbreviate kvm.sh summary lines
  rcutorture: Print end-of-test state in kvm.sh summary
  rcutorture: Print end-of-test state
  torture: Fold parse-torture.sh into parse-console.sh
  torture: Add a script to edit output from failed runs
  rcu: Update list of rcu_future_grace_period() trace events
  rcu: Drop early GP request check from rcu_gp_kthread()
  rcu: Simplify and inline cpu_needs_another_gp()
  rcu: The rcu_gp_cleanup() function does not need cpu_needs_another_gp()
  rcu: Make rcu_start_this_gp() check for out-of-range requests
  rcu: Add funnel locking to rcu_start_this_gp()
  rcu: Make rcu_start_future_gp() caller select grace period
  rcu: Inline rcu_start_gp_advanced() into rcu_start_future_gp()
  rcu: Clear request other than RCU_GP_FLAG_INIT at GP end
  rcu: Cleanup, don't put ->completed into an int
  rcu: Switch __rcu_process_callbacks() to rcu_accelerate_cbs()
  rcu: Avoid __call_rcu_core() root rcu_node ->lock acquisition
  rcu: Make rcu_migrate_callbacks wake GP kthread when needed
  ...
2018-06-04 15:54:04 -07:00
Steven Rostedt (VMware) 6167c205ca ring-buffer: Fix a bunch of typos in comments
An anonymous source sent me a bunch of typo fixes in the comments of
ring_buffer.c file. That source did not want to be associated to this patch
because they don't want to be known as "one of those" commiters (you know who
you are!). They gave me permission to sign this off in my own name.

Suggested-by: One-of-those-commiters@YouKnowWhoYouAre.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-06-04 17:28:19 -04:00
Yonghong Song 34ea38ca27 bpf: guard bpf_get_current_cgroup_id() with CONFIG_CGROUPS
Commit bf6fa2c893 ("bpf: implement bpf_get_current_cgroup_id()
helper") introduced a new helper bpf_get_current_cgroup_id().
The helper has a dependency on CONFIG_CGROUPS.

When CONFIG_CGROUPS is not defined, using the helper will result
the following verifier error:
  kernel subsystem misconfigured func bpf_get_current_cgroup_id#80
which is hard for users to interpret.
Guarding the reference to bpf_get_current_cgroup_id_proto with
CONFIG_CGROUPS will result in below better message:
  unknown func bpf_get_current_cgroup_id#80

Fixes: bf6fa2c893 ("bpf: implement bpf_get_current_cgroup_id() helper")
Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-06-04 21:52:26 +02:00
Yonghong Song bf6fa2c893 bpf: implement bpf_get_current_cgroup_id() helper
bpf has been used extensively for tracing. For example, bcc
contains an almost full set of bpf-based tools to trace kernel
and user functions/events. Most tracing tools are currently
either filtered based on pid or system-wide.

Containers have been used quite extensively in industry and
cgroup is often used together to provide resource isolation
and protection. Several processes may run inside the same
container. It is often desirable to get container-level tracing
results as well, e.g. syscall count, function count, I/O
activity, etc.

This patch implements a new helper, bpf_get_current_cgroup_id(),
which will return cgroup id based on the cgroup within which
the current task is running.

The later patch will provide an example to show that
userspace can get the same cgroup id so it could
configure a filter or policy in the bpf program based on
task cgroup id.

The helper is currently implemented for tracing. It can
be added to other program types as well when needed.

Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-06-03 18:22:41 -07:00
Daniel Borkmann bc23105ca0 bpf: fix context access in tracing progs on 32 bit archs
Wang reported that all the testcases for BPF_PROG_TYPE_PERF_EVENT
program type in test_verifier report the following errors on x86_32:

  172/p unpriv: spill/fill of different pointers ldx FAIL
  Unexpected error message!
  0: (bf) r6 = r10
  1: (07) r6 += -8
  2: (15) if r1 == 0x0 goto pc+3
  R1=ctx(id=0,off=0,imm=0) R6=fp-8,call_-1 R10=fp0,call_-1
  3: (bf) r2 = r10
  4: (07) r2 += -76
  5: (7b) *(u64 *)(r6 +0) = r2
  6: (55) if r1 != 0x0 goto pc+1
  R1=ctx(id=0,off=0,imm=0) R2=fp-76,call_-1 R6=fp-8,call_-1 R10=fp0,call_-1 fp-8=fp
  7: (7b) *(u64 *)(r6 +0) = r1
  8: (79) r1 = *(u64 *)(r6 +0)
  9: (79) r1 = *(u64 *)(r1 +68)
  invalid bpf_context access off=68 size=8

  378/p check bpf_perf_event_data->sample_period byte load permitted FAIL
  Failed to load prog 'Permission denied'!
  0: (b7) r0 = 0
  1: (71) r0 = *(u8 *)(r1 +68)
  invalid bpf_context access off=68 size=1

  379/p check bpf_perf_event_data->sample_period half load permitted FAIL
  Failed to load prog 'Permission denied'!
  0: (b7) r0 = 0
  1: (69) r0 = *(u16 *)(r1 +68)
  invalid bpf_context access off=68 size=2

  380/p check bpf_perf_event_data->sample_period word load permitted FAIL
  Failed to load prog 'Permission denied'!
  0: (b7) r0 = 0
  1: (61) r0 = *(u32 *)(r1 +68)
  invalid bpf_context access off=68 size=4

  381/p check bpf_perf_event_data->sample_period dword load permitted FAIL
  Failed to load prog 'Permission denied'!
  0: (b7) r0 = 0
  1: (79) r0 = *(u64 *)(r1 +68)
  invalid bpf_context access off=68 size=8

Reason is that struct pt_regs on x86_32 doesn't fully align to 8 byte
boundary due to its size of 68 bytes. Therefore, bpf_ctx_narrow_access_ok()
will then bail out saying that off & (size_default - 1) which is 68 & 7
doesn't cleanly align in the case of sample_period access from struct
bpf_perf_event_data, hence verifier wrongly thinks we might be doing an
unaligned access here though underlying arch can handle it just fine.
Therefore adjust this down to machine size and check and rewrite the
offset for narrow access on that basis. We also need to fix corresponding
pe_prog_is_valid_access(), since we hit the check for off % size != 0
(e.g. 68 % 8 -> 4) in the first and last test. With that in place, progs
for tracing work on x86_32.

Reported-by: Wang YanQing <udknight@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Wang YanQing <udknight@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-06-03 07:46:56 -07:00
David S. Miller 9c54aeb03a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Filling in the padding slot in the bpf structure as a bug fix in 'ne'
overlapped with actually using that padding area for something in
'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-03 09:31:58 -04:00
Sean Young 170a7e3ea0 bpf: bpf_prog_array_copy() should return -ENOENT if exclude_prog not found
This makes is it possible for bpf prog detach to return -ENOENT.

Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-30 12:37:38 +02:00
Steven Rostedt (VMware) 3be4c1e52a tracing: Allow histogram triggers to access ftrace internal events
Now that trace_marker can have triggers, including a histogram triggers, the
onmatch() and onmax() access the trace event. To do so, the search routine
to find the event file needs to use the raw __find_event_file() that does
not filter out ftrace events.

Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-29 08:29:22 -04:00
Steven Rostedt (VMware) 10f20e9f9d tracing: Have zero size length in filter logic be full string
As strings in trace events may not have a nul terminating character, the
filter string compares use the defined string length for the field for the
compares.

The trace_marker records data slightly different than do normal events. It's
size is zero, meaning that the string is the rest of the array, and that the
string also ends with '\0'.

If the size is zero, assume that the string is nul terminated and read the
string in question as is.

Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-29 08:29:04 -04:00
Steven Rostedt (VMware) 3dd8095368 tracing: Add trigger file for trace_markers tracefs/ftrace/print
Allow writing to the trace_markers file initiate triggers defined in
tracefs/ftrace/print/trigger file. This will allow of user space to trigger
the same type of triggers (including histograms) that the trace events use.

Had to create a ftrace_event_register() function that will become the
trace_marker print event's reg() function. This is required because of how
triggers are enabled:

  event_trigger_write() {
    event_trigger_regex_write() {
      trigger_process_regex() {
        for p in trigger_commands {
          p->func(); /* trigger_snapshot_cmd->func */
            event_trigger_callback() {
              cmd_ops->reg() /* register_trigger() */ {
                trace_event_trigger_enable_disable() {
                  trace_event_enable_disable() {
                    call->class->reg();

Without the reg() function, the trigger code will call a NULL pointer and
crash the system.

Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Karim Yaghmour <karim.yaghmour@opersys.com>
Cc: Brendan Gregg <bgregg@netflix.com>
Suggested-by: Joel Fernandes <joelaf@google.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-29 08:28:53 -04:00
Steven Rostedt (VMware) 5d948c86bb tracing: Do not show filter file for ftrace internal events
The filter file in the ftrace internal events, like in
/sys/kernel/tracing/events/ftrace/function/filter is not attached to any
functionality. Do not create them as they are meaningless.

In the future, if an ftrace internal event gets filter functionality, then
it will need to create it directly.

Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-29 08:28:46 -04:00
Steven Rostedt (VMware) af3dcb53bd tracing: Add brackets in ftrace event dynamic arrays
The dynamic arrays defined for ftrace internal events, such as the buf field
for trace_marker (ftrace/print) did not have brackets which makes the filter
code not accept it as a string. This is not currently an issues because the
filter code doesn't do anything for these events, but they will in the
future, and this needs to be fixed for when it does.

Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-29 08:28:37 -04:00
Steven Rostedt (VMware) 58b9254757 tracing: Have event_trace_init() called by trace_init_tracefs()
Instead of having both trace_init_tracefs() and event_trace_init() be called
by fs_initcall() routines, have event_trace_init() called directly by
trace_init_tracefs(). This will guarantee order of how the events are
created with respect to the rest of the ftrace infrastructure. This is
needed to be able to assoctiate event files with ftrace internal events,
such as the trace_marker.

Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-29 08:28:29 -04:00
Steven Rostedt (VMware) 3c96529c07 tracing: Add __find_event_file() to find event files without restrictions
By adding the function __find_event_file() that can search for files without
restrictions, such as if the event associated with the file has a reg
function, or if it has the "ignore" flag set, the files that are associated
to ftrace internal events (like trace_marker and function events) can be
found and used.

find_event_file() still returns a "filtered" file, as most callers need a
valid trace event file. One created by the trace_events.h macros and not one
created for parsing ftrace specific events.

Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-29 08:28:18 -04:00
Steven Rostedt (VMware) c94e45bc38 tracing: Do not reference event data in post call triggers
Trace event triggers can be called before or after the event has been
committed. If it has been called after the commit, there's a possibility
that the event no longer exists. Currently, the two post callers is the
trigger to disable tracing (traceoff) and the one that will record a stack
dump (stacktrace). Neither of them reference the trace event entry record,
as that would lead to a race condition that could pass in corrupted data.

To prevent any other users of the post data triggers from using the trace
event record, pass in NULL to the post call trigger functions for the event
record, as they should never need to use them in the first place.

This does not fix any bug, but prevents bugs from happening by new post call
trigger users.

Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-29 08:28:02 -04:00
Steven Rostedt (VMware) 2824f50332 tracing: Make the snapshot trigger work with instances
The snapshot trigger currently only affects the main ring buffer, even when
it is used by the instances. This can be confusing as the snapshot trigger
is listed in the instance.

 > # cd /sys/kernel/tracing
 > # mkdir instances/foo
 > # echo snapshot > instances/foo/events/syscalls/sys_enter_fchownat/trigger
 > # echo top buffer > trace_marker
 > # echo foo buffer > instances/foo/trace_marker
 > # touch /tmp/bar
 > # chown rostedt /tmp/bar
 > # cat instances/foo/snapshot
 # tracer: nop
 #
 #
 # * Snapshot is freed *
 #
 # Snapshot commands:
 # echo 0 > snapshot : Clears and frees snapshot buffer
 # echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.
 #                      Takes a snapshot of the main buffer.
 # echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)
 #                      (Doesn't have to be '2' works with any number that
 #                       is not a '0' or '1')

 > # cat snapshot
 # tracer: nop
 #
 #                              _-----=> irqs-off
 #                             / _----=> need-resched
 #                            | / _---=> hardirq/softirq
 #                            || / _--=> preempt-depth
 #                            ||| /     delay
 #           TASK-PID   CPU#  ||||    TIMESTAMP  FUNCTION
 #              | |       |   ||||       |         |
             bash-1189  [000] ....   111.488323: tracing_mark_write: top buffer

Not only did the snapshot occur in the top level buffer, but the instance
snapshot buffer should have been allocated, and it is still free.

Cc: stable@vger.kernel.org
Fixes: 85f2b08268 ("tracing: Add basic event trigger framework")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-28 12:49:32 -04:00
Steven Rostedt (VMware) 86b389ff22 tracing: Fix crash when freeing instances with event triggers
If a instance has an event trigger enabled when it is freed, it could cause
an access of free memory. Here's the case that crashes:

 # cd /sys/kernel/tracing
 # mkdir instances/foo
 # echo snapshot > instances/foo/events/initcall/initcall_start/trigger
 # rmdir instances/foo

Would produce:

 general protection fault: 0000 [#1] PREEMPT SMP PTI
 Modules linked in: tun bridge ...
 CPU: 5 PID: 6203 Comm: rmdir Tainted: G        W         4.17.0-rc4-test+ #933
 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016
 RIP: 0010:clear_event_triggers+0x3b/0x70
 RSP: 0018:ffffc90003783de0 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 6b6b6b6b6b6b6b2b RCX: 0000000000000000
 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8800c7130ba0
 RBP: ffffc90003783e00 R08: ffff8801131993f8 R09: 0000000100230016
 R10: ffffc90003783d80 R11: 0000000000000000 R12: ffff8800c7130ba0
 R13: ffff8800c7130bd8 R14: ffff8800cc093768 R15: 00000000ffffff9c
 FS:  00007f6f4aa86700(0000) GS:ffff88011eb40000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f6f4a5aed60 CR3: 00000000cd552001 CR4: 00000000001606e0
 Call Trace:
  event_trace_del_tracer+0x2a/0xc5
  instance_rmdir+0x15c/0x200
  tracefs_syscall_rmdir+0x52/0x90
  vfs_rmdir+0xdb/0x160
  do_rmdir+0x16d/0x1c0
  __x64_sys_rmdir+0x17/0x20
  do_syscall_64+0x55/0x1a0
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

This was due to the call the clears out the triggers when an instance is
being deleted not removing the trigger from the link list.

Cc: stable@vger.kernel.org
Fixes: 85f2b08268 ("tracing: Add basic event trigger framework")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-27 20:54:44 -04:00
Yonghong Song 41bdc4b40e bpf: introduce bpf subcommand BPF_TASK_FD_QUERY
Currently, suppose a userspace application has loaded a bpf program
and attached it to a tracepoint/kprobe/uprobe, and a bpf
introspection tool, e.g., bpftool, wants to show which bpf program
is attached to which tracepoint/kprobe/uprobe. Such attachment
information will be really useful to understand the overall bpf
deployment in the system.

There is a name field (16 bytes) for each program, which could
be used to encode the attachment point. There are some drawbacks
for this approaches. First, bpftool user (e.g., an admin) may not
really understand the association between the name and the
attachment point. Second, if one program is attached to multiple
places, encoding a proper name which can imply all these
attachments becomes difficult.

This patch introduces a new bpf subcommand BPF_TASK_FD_QUERY.
Given a pid and fd, if the <pid, fd> is associated with a
tracepoint/kprobe/uprobe perf event, BPF_TASK_FD_QUERY will return
   . prog_id
   . tracepoint name, or
   . k[ret]probe funcname + offset or kernel addr, or
   . u[ret]probe filename + offset
to the userspace.
The user can use "bpftool prog" to find more information about
bpf program itself with prog_id.

Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-24 18:18:19 -07:00
Ingo Molnar 13a553199f Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
- Updates to the handling of expedited grace periods, perhaps most
   notably parallelizing their initialization.  Other changes
   include fixes from Boqun Feng.

 - Miscellaneous fixes.  These include an nvme fix from Nitzan Carmi
   that I am carrying because it depends on a new SRCU function
   cleanup_srcu_struct_quiesced().  This branch also includes fixes
   from Byungchul Park and Yury Norov.

 - Updates to reduce lock contention in the rcu_node combining tree.
   These are in preparation for the consolidation of RCU-bh,
   RCU-preempt, and RCU-sched into a single flavor, which was
   requested by Linus Torvalds in response to a security flaw
   whose root cause included confusion between the multiple flavors
   of RCU.

 - Torture-test updates that save their users some time and effort.

Conflicts:
	drivers/nvme/host/core.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-16 09:34:51 +02:00
Paul E. McKenney cee4393989 rcu: Rename cond_resched_rcu_qs() to cond_resched_tasks_rcu_qs()
Commit e31d28b6ab ("trace: Eliminate cond_resched_rcu_qs() in favor
of cond_resched()") substituted cond_resched() for the earlier call
to cond_resched_rcu_qs().  However, the new-age cond_resched() does
not do anything to help RCU-tasks grace periods because (1) RCU-tasks
is only enabled when CONFIG_PREEMPT=y and (2) cond_resched() is a
complete no-op when preemption is enabled.  This situation results
in hangs when running the trace benchmarks.

A number of potential fixes were discussed on LKML
(https://lkml.kernel.org/r/20180224151240.0d63a059@vmware.local.home),
including making cond_resched() not be a no-op; making cond_resched()
not be a no-op, but only when running tracing benchmarks; reverting
the aforementioned commit (which works because cond_resched_rcu_qs()
does provide an RCU-tasks quiescent state; and adding a call to the
scheduler/RCU rcu_note_voluntary_context_switch() function.  All were
deemed unsatisfactory, either due to added cond_resched() overhead or
due to magic functions inviting cargo culting.

This commit renames cond_resched_rcu_qs() to cond_resched_tasks_rcu_qs(),
which provides a clear hint as to what this function is doing and
why and where it should be used, and then replaces the call to
cond_resched() with cond_resched_tasks_rcu_qs() in the trace benchmark's
benchmark_event_kthread() function.

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Nicholas Piggin <npiggin@gmail.com>
2018-05-15 10:27:29 -07:00
David S. Miller b2d6cee117 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The bpf syscall and selftests conflicts were trivial
overlapping changes.

The r8169 change involved moving the added mdelay from 'net' into a
different function.

A TLS close bug fix overlapped with the splitting of the TLS state
into separate TX and RX parts.  I just expanded the tests in the bug
fix from "ctx->conf == X" into "ctx->tx_conf == X && ctx->rx_conf
== X".

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-11 20:53:22 -04:00
Steven Rostedt (VMware) dc432c3d7f tracing: Fix regex_match_front() to not over compare the test string
The regex match function regex_match_front() in the tracing filter logic,
was fixed to test just the pattern length from testing the entire test
string. That is, it went from strncmp(str, r->pattern, len) to
strcmp(str, r->pattern, r->len).

The issue is that str is not guaranteed to be nul terminated, and if r->len
is greater than the length of str, it can access more memory than is
allocated.

The solution is to add a simple test if (len < r->len) return 0.

Cc: stable@vger.kernel.org
Fixes: 285caad415 ("tracing/filters: Fix MATCH_FRONT_ONLY filter matching")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-11 10:56:42 -04:00
David S. Miller 01adc4851a Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Minor conflict, a CHECK was placed into an if() statement
in net-next, whilst a newline was added to that CHECK
call in 'net'.  Thanks to Daniel for the merge resolution.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-07 23:35:08 -04:00
Linus Torvalds 4b293907d3 Some of the files in the tracing directory show file mode 0444
when they are writable by root. To fix the confusion, they should
 be 0644. Note, either case root can still write to them.
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Merge tag 'trace-v4.17-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Some of the files in the tracing directory show file mode 0444 when
  they are writable by root. To fix the confusion, they should be 0644.
  Note, either case root can still write to them.

  Zhengyuan asked why I never applied that patch (the first one is from
  2014!). I simply forgot about it. /me lowers head in shame"

* tag 'trace-v4.17-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix the file mode of stack tracer
  ftrace: Have set_graph_* files have normal file modes
2018-05-04 20:57:28 -10:00
Zhengyuan Liu 0c5a9acc8b tracing: Fix the file mode of stack tracer
It looks weird that the stack_trace_filter file can be written by root
but shows that it does not have write permission by ll command.

Link: http://lkml.kernel.org/r/1518054113-28096-1-git-send-email-liuzhengyuan@kylinos.cn

Signed-off-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-03 11:58:05 -04:00
Chen LinX 1ce0500d23 ftrace: Have set_graph_* files have normal file modes
The set_graph_function and set_graph_notrace file mode should be 0644
instead of 0444 as they are writeable. Note, the mode appears to be ignored
regardless, but they should at least look sane.

Link: http://lkml.kernel.org/r/1409725869-4501-1-git-send-email-linx.z.chen@intel.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Chen LinX <linx.z.chen@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-03 11:55:31 -04:00
Michael Ellerman 0ea5ee0351 tracing: Remove PPC32 wart from config TRACING_SUPPORT
config TRACING_SUPPORT has an exception for PPC32, because PPC32
didn't have irqflags tracing support.

But that hasn't been true since commit 5d38902c48 ("powerpc: Add
irqtrace support for 32-bit powerpc") (Jun 2009).

So remove the exception for PPC32 and the comment.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-03 23:08:29 +10:00
Linus Torvalds f4ef6a438c Various fixes in tracing:
- Tracepoints should not give warning on OOM failures
 
  - Use special field for function pointer in trace event
 
  - Fix igrab issues in uprobes
 
  - Fixes to the new histogram triggers
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Merge tag 'trace-v4.17-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Various fixes in tracing:

   - Tracepoints should not give warning on OOM failures

   - Use special field for function pointer in trace event

   - Fix igrab issues in uprobes

   - Fixes to the new histogram triggers"

* tag 'trace-v4.17-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracepoint: Do not warn on ENOMEM
  tracing: Add field modifier parsing hist error for hist triggers
  tracing: Add field parsing hist error for hist triggers
  tracing: Restore proper field flag printing when displaying triggers
  tracing: initcall: Ordered comparison of function pointers
  tracing: Remove igrab() iput() call from uprobes.c
  tracing: Fix bad use of igrab in trace_uprobe.c
2018-05-02 17:38:37 -10:00
Teng Qin 7ef3771205 bpf: Allow bpf_current_task_under_cgroup in interrupt
Currently, the bpf_current_task_under_cgroup helper has a check where if
the BPF program is running in_interrupt(), it will return -EINVAL. This
prevents the helper to be used in many useful scenarios, particularly
BPF programs attached to Perf Events.

This commit removes the check. Tested a few NMI (Perf Event) and some
softirq context, the helper returns the correct result.

Signed-off-by: Teng Qin <qinteng@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-04-29 09:18:04 -07:00
Linus Torvalds 810fb07a9b Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
 "Two fixes from the timer departement:

   - Fix a long standing issue in the NOHZ tick code which causes RB
     tree corruption, delayed timers and other malfunctions. The cause
     for this is code which modifies the expiry time of an enqueued
     hrtimer.

   - Revert the CLOCK_MONOTONIC/CLOCK_BOOTTIME unification due to
     regression reports. Seems userspace _is_ relying on the documented
     behaviour despite our hope that it wont"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert: Unify CLOCK_MONOTONIC and CLOCK_BOOTTIME
  tick/sched: Do not mess with an enqueued hrtimer
2018-04-29 09:03:25 -07:00
Yonghong Song c195651e56 bpf: add bpf_get_stack helper
Currently, stackmap and bpf_get_stackid helper are provided
for bpf program to get the stack trace. This approach has
a limitation though. If two stack traces have the same hash,
only one will get stored in the stackmap table,
so some stack traces are missing from user perspective.

This patch implements a new helper, bpf_get_stack, will
send stack traces directly to bpf program. The bpf program
is able to see all stack traces, and then can do in-kernel
processing or send stack traces to user space through
shared map or bpf_perf_event_output.

Acked-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-04-29 08:45:53 -07:00
Tom Zanussi dcf234577c tracing: Add field modifier parsing hist error for hist triggers
If the user specifies an invalid field modifier for a hist trigger,
the current code correctly flags that as an error, but doesn't tell
the user what happened.

Fix this by invoking hist_err() with an appropriate message when
invalid modifiers are specified.

Before:

  # echo 'hist:keys=pid:ts0=common_timestamp.junkusecs' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
  -su: echo: write error: Invalid argument
  # cat /sys/kernel/debug/tracing/events/sched/sched_wakeup/hist

After:

  # echo 'hist:keys=pid:ts0=common_timestamp.junkusecs' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
  -su: echo: write error: Invalid argument
  # cat /sys/kernel/debug/tracing/events/sched/sched_wakeup/hist
  ERROR: Invalid field modifier: junkusecs
    Last command: keys=pid:ts0=common_timestamp.junkusecs

Link: http://lkml.kernel.org/r/b043c59fa79acd06a5f14a1d44dee9e5a3cd1248.1524790601.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-26 21:39:58 -04:00
Tom Zanussi 5ec432d7bf tracing: Add field parsing hist error for hist triggers
If the user specifies a nonexistent field for a hist trigger, the
current code correctly flags that as an error, but doesn't tell the
user what happened.

Fix this by invoking hist_err() with an appropriate message when
nonexistent fields are specified.

Before:

  # echo 'hist:keys=pid:ts0=common_timestamp.usecs' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
  -su: echo: write error: Invalid argument
  # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist

After:

  # echo 'hist:keys=pid:ts0=common_timestamp.usecs' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
  -su: echo: write error: Invalid argument
  # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist
  ERROR: Couldn't find field: pid
    Last command: keys=pid:ts0=common_timestamp.usecs

Link: http://lkml.kernel.org/r/fdc8746969d16906120f162b99dd71c741e0b62c.1524790601.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Reported-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-26 21:39:32 -04:00
Tom Zanussi 608940dabe tracing: Restore proper field flag printing when displaying triggers
The flag-printing code used when displaying hist triggers somehow got
dropped during refactoring of the inter-event patchset.  This restores
it.

Below are a couple examples - in the first case, .usecs wasn't being
displayed properly for common_timestamps and the second illustrates
the same for other flags such as .execname.

Before:

  # echo 'hist:key=common_pid.execname:val=count:sort=count' > /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/trigger
  # cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/trigger
  hist:keys=common_pid:vals=hitcount,count:sort=count:size=2048 [active]

  # echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
  # cat /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
  hist:keys=pid:vals=hitcount:ts0=common_timestamp:sort=hitcount:size=2048:clock=global if comm=="cyclictest" [active]

After:

  # echo 'hist:key=common_pid.execname:val=count:sort=count' > /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/trigger
  # cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/trigger
  hist:keys=common_pid.execname:vals=hitcount,count:sort=count:size=2048 [active]

  # echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
  # cat /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
  hist:keys=pid:vals=hitcount:ts0=common_timestamp.usecs:sort=hitcount:size=2048:clock=global if comm=="cyclictest" [active]

Link: http://lkml.kernel.org/r/492bab42ff21806600af98a8ea901af10efbee0c.1524790601.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-26 21:38:43 -04:00
Linus Torvalds 47b5ece937 Following tracing fixes:
- Add workqueue forward declaration (for new work, but a nice clean up)
 
  - seftest fixes for the new histogram code
 
  - Print output fix for hwlat tracer
 
  - Fix missing system call events - due to change in x86 syscall naming
 
  - Fix kprobe address being used by perf being hashed
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Merge tag 'trace-v4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Add workqueue forward declaration (for new work, but a nice clean up)

 - seftest fixes for the new histogram code

 - Print output fix for hwlat tracer

 - Fix missing system call events - due to change in x86 syscall naming

 - Fix kprobe address being used by perf being hashed

* tag 'trace-v4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix missing tab for hwlat_detector print format
  selftests: ftrace: Add a testcase for multiple actions on trigger
  selftests: ftrace: Fix trigger extended error testcase
  kprobes: Fix random address output of blacklist file
  tracing: Fix kernel crash while using empty filter with perf
  tracing/x86: Update syscall trace events to handle new prefixed syscall func names
  tracing: Add missing forward declaration
2018-04-26 16:22:47 -07:00
Song Liu 0c92c7a3c5 tracing: Fix bad use of igrab in trace_uprobe.c
As Miklos reported and suggested:

  This pattern repeats two times in trace_uprobe.c and in
  kernel/events/core.c as well:

      ret = kern_path(filename, LOOKUP_FOLLOW, &path);
      if (ret)
          goto fail_address_parse;

      inode = igrab(d_inode(path.dentry));
      path_put(&path);

  And it's wrong.  You can only hold a reference to the inode if you
  have an active ref to the superblock as well (which is normally
  through path.mnt) or holding s_umount.

  This way unmounting the containing filesystem while the tracepoint is
  active will give you the "VFS: Busy inodes after unmount..." message
  and a crash when the inode is finally put.

  Solution: store path instead of inode.

This patch fixes two instances in trace_uprobe.c. struct path is added to
struct trace_uprobe to keep the inode and containing mount point
referenced.

Link: http://lkml.kernel.org/r/20180423172135.4050588-1-songliubraving@fb.com

Fixes: f3f096cfed ("tracing: Provide trace events interface for uprobes")
Fixes: 33ea4b2427 ("perf/core: Implement the 'perf_uprobe' PMU")
Cc: stable@vger.kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Howard McLauchlan <hmclauchlan@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Miklos Szeredi <mszeredi@redhat.com>
Reported-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-26 14:49:55 -04:00
Thomas Gleixner a3ed0e4393 Revert: Unify CLOCK_MONOTONIC and CLOCK_BOOTTIME
Revert commits

92af4dcb4e ("tracing: Unify the "boot" and "mono" tracing clocks")
127bfa5f43 ("hrtimer: Unify MONOTONIC and BOOTTIME clock behavior")
7250a4047a ("posix-timers: Unify MONOTONIC and BOOTTIME clock behavior")
d6c7270e91 ("timekeeping: Remove boot time specific code")
f2d6fdbfd2 ("Input: Evdev - unify MONOTONIC and BOOTTIME clock behavior")
d6ed449afd ("timekeeping: Make the MONOTONIC clock behave like the BOOTTIME clock")
72199320d4 ("timekeeping: Add the new CLOCK_MONOTONIC_ACTIVE clock")

As stated in the pull request for the unification of CLOCK_MONOTONIC and
CLOCK_BOOTTIME, it was clear that we might have to revert the change.

As reported by several folks systemd and other applications rely on the
documented behaviour of CLOCK_MONOTONIC on Linux and break with the above
changes. After resume daemons time out and other timeout related issues are
observed. Rafael compiled this list:

* systemd kills daemons on resume, after >WatchdogSec seconds
  of suspending (Genki Sky).  [Verified that that's because systemd uses
  CLOCK_MONOTONIC and expects it to not include the suspend time.]

* systemd-journald misbehaves after resume:
  systemd-journald[7266]: File /var/log/journal/016627c3c4784cd4812d4b7e96a34226/system.journal
corrupted or uncleanly shut down, renaming and replacing.
  (Mike Galbraith).

* NetworkManager reports "networking disabled" and networking is broken
  after resume 50% of the time (Pavel).  [May be because of systemd.]

* MATE desktop dims the display and starts the screensaver right after
  system resume (Pavel).

* Full system hang during resume (me).  [May be due to systemd or NM or both.]

That happens on debian and open suse systems.

It's sad, that these problems were neither catched in -next nor by those
folks who expressed interest in this change.

Reported-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Reported-by: Genki Sky <sky@genki.is>,
Reported-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kevin Easton <kevin@guarana.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Salyzyn <salyzyn@android.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
2018-04-26 14:53:32 +02:00
Peter Xu 9a0fd67530 tracing: Fix missing tab for hwlat_detector print format
It's been missing for a while but no one is touching that up.  Fix it.

Link: http://lkml.kernel.org/r/20180315060639.9578-1-peterx@redhat.com

CC: Ingo Molnar <mingo@kernel.org>
Cc:stable@vger.kernel.org
Fixes: 7b2c862501 ("tracing: Add NMI tracing in hwlat detector")
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-25 10:28:46 -04:00
Ravi Bangoria ba16293dad tracing: Fix kernel crash while using empty filter with perf
Kernel is crashing when user tries to record 'ftrace:function' event
with empty filter:

  # perf record -e ftrace:function --filter="" ls

  # dmesg
  BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
  Oops: 0000 [#1] SMP PTI
  ...
  RIP: 0010:ftrace_profile_set_filter+0x14b/0x2d0
  RSP: 0018:ffffa4a7c0da7d20 EFLAGS: 00010246
  RAX: ffffa4a7c0da7d64 RBX: 0000000000000000 RCX: 0000000000000006
  RDX: 0000000000000000 RSI: 0000000000000092 RDI: ffff8c48ffc968f0
  ...
  Call Trace:
   _perf_ioctl+0x54a/0x6b0
   ? rcu_all_qs+0x5/0x30
  ...

After patch:
  # perf record -e ftrace:function --filter="" ls
  failed to set filter "" on event ftrace:function with 22 (Invalid argument)

Also, if user tries to echo "" > filter, it used to throw an error.
This behavior got changed by commit 80765597bc ("tracing: Rewrite
filter logic to be simpler and faster"). This patch restores the
behavior as a side effect:

Before patch:
  # echo "" > filter
  #

After patch:
  # echo "" > filter
  bash: echo: write error: Invalid argument
  #

Link: http://lkml.kernel.org/r/20180420150758.19787-1-ravi.bangoria@linux.ibm.com

Fixes: 80765597bc ("tracing: Rewrite filter logic to be simpler and faster")
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-25 10:27:55 -04:00
Linus Torvalds 24cac7009c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Fix rtnl deadlock in ipvs, from Julian Anastasov.

 2) s390 qeth fixes from Julian Wiedmann (control IO completion stalls,
    bad MAC address update sequence, request side races on command IO
    timeouts).

 3) Handle seq_file overflow properly in l2tp, from Guillaume Nault.

 4) Fix VLAN priority mappings in cpsw driver, from Ivan Khoronzhuk.

 5) Packet scheduler ife action fixes (malformed TLV lengths, etc.) from
    Alexander Aring.

 6) Fix out of bounds access in tcp md5 option parser, from Jann Horn.

 7) Missing netlink attribute policies in rtm_ipv6_policy table, from
    Eric Dumazet.

 8) Missing socket address length checks in l2tp and pppoe connect, from
    Guillaume Nault.

 9) Fix netconsole over team and bonding, from Xin Long.

10) Fix race with AF_PACKET socket state bitfields, from Willem de
    Bruijn.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (51 commits)
  ice: Fix insufficient memory issue in ice_aq_manage_mac_read
  sfc: ARFS filter IDs
  net: ethtool: Add missing kernel doc for FEC parameters
  packet: fix bitfield update race
  ice: Do not check INTEVENT bit for OICR interrupts
  ice: Fix incorrect comment for action type
  ice: Fix initialization for num_nodes_added
  igb: Fix the transmission mode of queue 0 for Qav mode
  ixgbevf: ensure xdp_ring resources are free'd on error exit
  team: fix netconsole setup over team
  amd-xgbe: Only use the SFP supported transceiver signals
  amd-xgbe: Improve KR auto-negotiation and training
  amd-xgbe: Add pre/post auto-negotiation phy hooks
  pppoe: check sockaddr length in pppoe_connect()
  l2tp: check sockaddr length in pppol2tp_connect()
  net: phy: marvell: clear wol event before setting it
  ipv6: add RTA_TABLE and RTA_PREFSRC to rtm_ipv6_policy
  bonding: do not set slave_dev npinfo before slave_enable_netpoll in bond_enslave
  tcp: don't read out-of-bounds opsize
  ibmvnic: Clean actual number of RX or TX pools
  ...
2018-04-24 14:16:40 -07:00
David S. Miller 986e54cd68 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2018-04-21

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Fix a deadlock between mm->mmap_sem and bpf_event_mutex when
   one task is detaching a BPF prog via perf_event_detach_bpf_prog()
   and another one dumping through bpf_prog_array_copy_info(). For
   the latter we move the copy_to_user() out of the bpf_event_mutex
   lock to fix it, from Yonghong.

2) Fix test_sock and test_sock_addr.sh failures. The former was
   hitting rlimit issues and the latter required ping to specify
   the address family, from Yonghong.

3) Remove a dead check in sockmap's sock_map_alloc(), from Jann.

4) Add generated files to BPF kselftests gitignore that were previously
   missed, from Anders.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-22 21:15:59 -04:00
Song Liu 5c8dad48e4 trace_kprobe: Remove warning message "Could not insert probe at..."
This warning message is not very helpful, as the return value should
already show information about the error. Also, this message will
spam dmesg if the user space does testing in a loop, like:

    for x in {0..5}
    do
        echo p:xx xx+$x >> /sys/kernel/debug/tracing/kprobe_events
    done

Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Song Liu <songliubraving@fb.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/20180413185513.3626052-1-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-17 07:54:57 +02:00
Linus Torvalds 174e719439 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull more perf updates from Thomas Gleixner:
 "A rather large set of perf updates:

  Kernel:

   - Fix various initialization issues

   - Prevent creating [ku]probes for not CAP_SYS_ADMIN users

  Tooling:

   - Show only failing syscalls with 'perf trace --failure' (Arnaldo
     Carvalho de Melo)

            e.g: See what 'openat' syscalls are failing:

        # perf trace --failure -e openat
         762.323 ( 0.007 ms): VideoCapture/4566 openat(dfd: CWD, filename: /dev/video2) = -1 ENOENT No such file or directory
         <SNIP N /dev/videoN open attempts... sigh, where is that improvised camera lid?!? >
         790.228 ( 0.008 ms): VideoCapture/4566 openat(dfd: CWD, filename: /dev/video63) = -1 ENOENT No such file or directory
        ^C#

   - Show information about the event (freq, nr_samples, total
     period/nr_events) in the annotate --tui and --stdio2 'perf
     annotate' output, similar to the first line in the 'perf report
     --tui', but just for the samples for a the annotated symbol
     (Arnaldo Carvalho de Melo)

   - Introduce 'perf version --build-options' to show what features were
     linked, aliased as well as a shorter 'perf -vv' (Jin Yao)

   - Add a "dso_size" sort order (Kim Phillips)

   - Remove redundant ')' in the tracepoint output in 'perf trace'
     (Changbin Du)

   - Synchronize x86's cpufeatures.h, no effect on toolss (Arnaldo
     Carvalho de Melo)

   - Show group details on the title line in the annotate browser and
     'perf annotate --stdio2' output, so that the per-event columns can
     have headers (Arnaldo Carvalho de Melo)

   - Fixup vertical line separating metrics from instructions and
     cleaning unused lines at the bottom, both in the annotate TUI
     browser (Arnaldo Carvalho de Melo)

   - Remove duplicated 'samples' in lost samples warning in
     'perf report' (Arnaldo Carvalho de Melo)

   - Synchronize i915_drm.h, silencing the perf build process,
     automagically adding support for the new DRM_I915_QUERY ioctl
     (Arnaldo Carvalho de Melo)

   - Make auxtrace_queues__add_buffer() allocate struct buffer, from a
     patchkit already applied (Adrian Hunter)

   - Fix the --stdio2/TUI annotate output to include group details, be
     it for a recorded '{a,b,f}' explicit event group or when forcing
     group display using 'perf report --group' for a set of events not
     recorded as a group (Arnaldo Carvalho de Melo)

   - Fix display artifacts in the ui browser (base class for the
     annotate and main report/top TUI browser) related to the extra
     title lines work (Arnaldo Carvalho de Melo)

   - perf auxtrace refactorings, leftovers from a previously partially
     processed patchset (Adrian Hunter)

   - Fix the builtin clang build (Sandipan Das, Arnaldo Carvalho de
     Melo)

   - Synchronize i915_drm.h, silencing a perf build warning and in the
     process automagically adding support for a new ioctl command
     (Arnaldo Carvalho de Melo)

   - Fix a strncpy issue in uprobe tracing"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
  perf/core: Need CAP_SYS_ADMIN to create k/uprobe with perf_event_open()
  tracing/uprobe_event: Fix strncpy corner case
  perf/core: Fix perf_uprobe_init()
  perf/core: Fix perf_kprobe_init()
  perf/core: Fix use-after-free in uprobe_perf_close()
  perf tests clang: Fix function name for clang IR test
  perf clang: Add support for recent clang versions
  perf tools: Fix perf builds with clang support
  perf tools: No need to include namespaces.h in util.h
  perf hists browser: Remove leftover from row returned from refresh
  perf hists browser: Show extra_title_lines in the 'D' debug hotkey
  perf auxtrace: Make auxtrace_queues__add_buffer() do CPU filtering
  tools headers uapi: Synchronize i915_drm.h
  perf report: Remove duplicated 'samples' in lost samples warning
  perf ui browser: Fixup cleaning unused lines at the bottom
  perf annotate browser: Fixup vertical line separating metrics from instructions
  perf annotate: Show group details on the title line
  perf auxtrace: Make auxtrace_queues__add_buffer() allocate struct buffer
  perf/x86/intel: Move regs->flags EXACT bit init
  perf trace: Remove redundant ')'
  ...
2018-04-15 12:36:31 -07:00
Linus Torvalds affb028071 A few clean ups and bug fixes
- Replace open coded "ARRAY_SIZE()" with macro
 
  - Updates to uprobes
 
  - Bug fix for perf event filter on error path
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Merge tag 'trace-v4.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "A few clean ups and bug fixes:

   - replace open coded "ARRAY_SIZE()" with macro

   - updates to uprobes

   - bug fix for perf event filter on error path"

* tag 'trace-v4.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Enforce passing in filter=NULL to create_filter()
  trace_uprobe: Simplify probes_seq_show()
  trace_uprobe: Use %lx to display offset
  tracing/uprobe: Add support for overlayfs
  tracing: Use ARRAY_SIZE() macro instead of open coding it
2018-04-12 20:54:01 -07:00
Steven Rostedt (VMware) 0b3dec05db tracing: Enforce passing in filter=NULL to create_filter()
There's some inconsistency with what to set the output parameter filterp
when passing to create_filter(..., struct event_filter **filterp).

Whatever filterp points to, should be NULL when calling this function. The
create_filter() calls create_filter_start() with a pointer to a local
"filter" variable that is set to NULL. The create_filter_start() has a
WARN_ON() if the passed in pointer isn't pointing to a value set to NULL.

Ideally, create_filter() should pass the filterp variable it received to
create_filter_start() and not hide it as with a local variable, this allowed
create_filter() to fail, and not update the passed in filter, and the caller
of create_filter() then tried to free filter, which was never initialized to
anything, causing memory corruption.

Link: http://lkml.kernel.org/r/00000000000032a0c30569916870@google.com

Fixes: 80765597bc ("tracing: Rewrite filter logic to be simpler and faster")
Reported-by: syzbot+dadcc936587643d7f568@syzkaller.appspotmail.com
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-11 11:31:08 -04:00
Ravi Bangoria a64b2c01e6 trace_uprobe: Simplify probes_seq_show()
Simplify probes_seq_show() function. No change in output
before and after patch.

Link: http://lkml.kernel.org/r/20180315082756.9050-2-ravi.bangoria@linux.vnet.ibm.com

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-11 11:31:07 -04:00
Ravi Bangoria 18d45b11d9 trace_uprobe: Use %lx to display offset
tu->offset is unsigned long, not a pointer, thus %lx should
be used to print it, not the %px.

Link: http://lkml.kernel.org/r/20180315082756.9050-1-ravi.bangoria@linux.vnet.ibm.com

Cc: stable@vger.kernel.org
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: 0e4d819d08 ("trace_uprobe: Display correct offset in uprobe_events")
Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-11 11:31:07 -04:00
Howard McLauchlan f0a2aa5a2a tracing/uprobe: Add support for overlayfs
uprobes cannot successfully attach to binaries located in a directory
mounted with overlayfs.

To verify, create directories for mounting overlayfs
(upper,lower,work,merge), move some binary into merge/ and use readelf
to obtain some known instruction of the binary. I used /bin/true and the
entry instruction(0x13b0):

	$ mount -t overlay overlay -o lowerdir=lower,upperdir=upper,workdir=work merge
	$ cd /sys/kernel/debug/tracing
	$ echo 'p:true_entry PATH_TO_MERGE/merge/true:0x13b0' > uprobe_events
	$ echo 1 > events/uprobes/true_entry/enable

This returns 'bash: echo: write error: Input/output error' and dmesg
tells us 'event trace: Could not enable event true_entry'

This change makes create_trace_uprobe() look for the real inode of a
dentry. In the case of normal filesystems, this simplifies to just
returning the inode. In the case of overlayfs(and similar fs) we will
obtain the underlying dentry and corresponding inode, upon which uprobes
can successfully register.

Running the example above with the patch applied, we can see that the
uprobe is enabled and will output to trace as expected.

Link: http://lkml.kernel.org/r/20180410231030.2720-1-hmclauchlan@fb.com

Reviewed-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Howard McLauchlan <hmclauchlan@fb.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-11 11:31:06 -04:00
Jérémy Lefaure 0a4d0564f0 tracing: Use ARRAY_SIZE() macro instead of open coding it
It is useless to re-invent the ARRAY_SIZE macro so let's use it instead
of DATA_CNT.

Found with Coccinelle with the following semantic patch:
@r depends on (org || report)@
type T;
T[] E;
position p;
@@
(
 (sizeof(E)@p /sizeof(*E))
|
 (sizeof(E)@p /sizeof(E[...]))
|
 (sizeof(E)@p /sizeof(T))
)

Link: http://lkml.kernel.org/r/20171016012250.26453-1-jeremy.lefaure@lse.epita.fr

Signed-off-by: Jérémy Lefaure <jeremy.lefaure@lse.epita.fr>
[ Removed useless include of kernel.h ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-11 11:30:33 -04:00
Yonghong Song 3a38bb98d9 bpf/tracing: fix a deadlock in perf_event_detach_bpf_prog
syzbot reported a possible deadlock in perf_event_detach_bpf_prog.
The error details:
  ======================================================
  WARNING: possible circular locking dependency detected
  4.16.0-rc7+ #3 Not tainted
  ------------------------------------------------------
  syz-executor7/24531 is trying to acquire lock:
   (bpf_event_mutex){+.+.}, at: [<000000008a849b07>] perf_event_detach_bpf_prog+0x92/0x3d0 kernel/trace/bpf_trace.c:854

  but task is already holding lock:
   (&mm->mmap_sem){++++}, at: [<0000000038768f87>] vm_mmap_pgoff+0x198/0x280 mm/util.c:353

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -> #1 (&mm->mmap_sem){++++}:
       __might_fault+0x13a/0x1d0 mm/memory.c:4571
       _copy_to_user+0x2c/0xc0 lib/usercopy.c:25
       copy_to_user include/linux/uaccess.h:155 [inline]
       bpf_prog_array_copy_info+0xf2/0x1c0 kernel/bpf/core.c:1694
       perf_event_query_prog_array+0x1c7/0x2c0 kernel/trace/bpf_trace.c:891
       _perf_ioctl kernel/events/core.c:4750 [inline]
       perf_ioctl+0x3e1/0x1480 kernel/events/core.c:4770
       vfs_ioctl fs/ioctl.c:46 [inline]
       do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686
       SYSC_ioctl fs/ioctl.c:701 [inline]
       SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
       do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
       entry_SYSCALL_64_after_hwframe+0x42/0xb7

  -> #0 (bpf_event_mutex){+.+.}:
       lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3920
       __mutex_lock_common kernel/locking/mutex.c:756 [inline]
       __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893
       mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
       perf_event_detach_bpf_prog+0x92/0x3d0 kernel/trace/bpf_trace.c:854
       perf_event_free_bpf_prog kernel/events/core.c:8147 [inline]
       _free_event+0xbdb/0x10f0 kernel/events/core.c:4116
       put_event+0x24/0x30 kernel/events/core.c:4204
       perf_mmap_close+0x60d/0x1010 kernel/events/core.c:5172
       remove_vma+0xb4/0x1b0 mm/mmap.c:172
       remove_vma_list mm/mmap.c:2490 [inline]
       do_munmap+0x82a/0xdf0 mm/mmap.c:2731
       mmap_region+0x59e/0x15a0 mm/mmap.c:1646
       do_mmap+0x6c0/0xe00 mm/mmap.c:1483
       do_mmap_pgoff include/linux/mm.h:2223 [inline]
       vm_mmap_pgoff+0x1de/0x280 mm/util.c:355
       SYSC_mmap_pgoff mm/mmap.c:1533 [inline]
       SyS_mmap_pgoff+0x462/0x5f0 mm/mmap.c:1491
       SYSC_mmap arch/x86/kernel/sys_x86_64.c:100 [inline]
       SyS_mmap+0x16/0x20 arch/x86/kernel/sys_x86_64.c:91
       do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
       entry_SYSCALL_64_after_hwframe+0x42/0xb7

  other info that might help us debug this:

   Possible unsafe locking scenario:

         CPU0                    CPU1
         ----                    ----
    lock(&mm->mmap_sem);
                                 lock(bpf_event_mutex);
                                 lock(&mm->mmap_sem);
    lock(bpf_event_mutex);

   *** DEADLOCK ***
  ======================================================

The bug is introduced by Commit f371b304f1 ("bpf/tracing: allow
user space to query prog array on the same tp") where copy_to_user,
which requires mm->mmap_sem, is called inside bpf_event_mutex lock.
At the same time, during perf_event file descriptor close,
mm->mmap_sem is held first and then subsequent
perf_event_detach_bpf_prog needs bpf_event_mutex lock.
Such a senario caused a deadlock.

As suggested by Daniel, moving copy_to_user out of the
bpf_event_mutex lock should fix the problem.

Fixes: f371b304f1 ("bpf/tracing: allow user space to query prog array on the same tp")
Reported-by: syzbot+dc5ca0e4c9bfafaf2bae@syzkaller.appspotmail.com
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-11 01:01:40 +02:00
Linus Torvalds 2a56bb596b New features:
- Tom Zanussi's extended histogram work
    This adds the synthetic events to have histograms from multiple event data
    Adds triggers "onmatch" and "onmax" to call the synthetic events
    Several updates to the histogram code from this
 
  - Allow way to nest ring buffer calls in the same context
 
  - Allow absolute time stamps in ring buffer
 
  - Rewrite of filter code parsing based on Al Viro's suggestions
 
  - Setting of trace_clock to global if TSC is unstable (on boot)
 
  - Better OOM handling when allocating large ring buffers
 
  - Added initcall tracepoints (consolidated initcall_debug code with them)
 
 And other various fixes and clean ups
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Merge tag 'trace-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "New features:

   - Tom Zanussi's extended histogram work.

     This adds the synthetic events to have histograms from multiple
     event data Adds triggers "onmatch" and "onmax" to call the
     synthetic events Several updates to the histogram code from this

   - Allow way to nest ring buffer calls in the same context

   - Allow absolute time stamps in ring buffer

   - Rewrite of filter code parsing based on Al Viro's suggestions

   - Setting of trace_clock to global if TSC is unstable (on boot)

   - Better OOM handling when allocating large ring buffers

   - Added initcall tracepoints (consolidated initcall_debug code with
     them)

  And other various fixes and clean ups"

* tag 'trace-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (68 commits)
  init: Have initcall_debug still work without CONFIG_TRACEPOINTS
  init, tracing: Have printk come through the trace events for initcall_debug
  init, tracing: instrument security and console initcall trace events
  init, tracing: Add initcall trace events
  tracing: Add rcu dereference annotation for test func that touches filter->prog
  tracing: Add rcu dereference annotation for filter->prog
  tracing: Fixup logic inversion on setting trace_global_clock defaults
  tracing: Hide global trace clock from lockdep
  ring-buffer: Add set/clear_current_oom_origin() during allocations
  ring-buffer: Check if memory is available before allocation
  lockdep: Add print_irqtrace_events() to __warn
  vsprintf: Do not preprocess non-dereferenced pointers for bprintf (%px and %pK)
  tracing: Uninitialized variable in create_tracing_map_fields()
  tracing: Make sure variable string fields are NULL-terminated
  tracing: Add action comparisons when testing matching hist triggers
  tracing: Don't add flag strings when displaying variable references
  tracing: Fix display of hist trigger expressions containing timestamps
  ftrace: Drop a VLA in module_exists()
  tracing: Mention trace_clock=global when warning about unstable clocks
  tracing: Default to using trace_global_clock if sched_clock is unstable
  ...
2018-04-10 11:27:30 -07:00
Masami Hiramatsu 50268a3d26 tracing/uprobe_event: Fix strncpy corner case
Fix string fetch function to terminate with NUL.
It is OK to drop the rest of string.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: security@kernel.org
Cc: 范龙飞 <long7573@126.com>
Fixes: 5baaa59ef0 ("tracing/probes: Implement 'memory' fetch method for uprobes")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-10 20:14:11 +02:00
Song Liu 0eadcc7a7b perf/core: Fix perf_uprobe_init()
Similarly to the uprobe PMU fix in perf_kprobe_init(), fix error
handling in perf_uprobe_init() as well.

Reported-by: 范龙飞 <long7573@126.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: e12f03d703 ("perf/core: Implement the 'perf_kprobe' PMU")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-10 07:33:10 +02:00
Masami Hiramatsu 5da13ab8b0 perf/core: Fix perf_kprobe_init()
Fix error handling in perf_kprobe_init():

	==================================================================
	BUG: KASAN: slab-out-of-bounds in strlen+0x8e/0xa0 lib/string.c:482
	Read of size 1 at addr ffff88003f9cc5c0 by task syz-executor2/23095

	CPU: 0 PID: 23095 Comm: syz-executor2 Not tainted 4.16.0+ #24
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
	Call Trace:
	 __dump_stack lib/dump_stack.c:77 [inline]
	 dump_stack+0xca/0x13e lib/dump_stack.c:113
	 print_address_description+0x6e/0x2c0 mm/kasan/report.c:256
	 kasan_report_error mm/kasan/report.c:354 [inline]
	 kasan_report+0x256/0x380 mm/kasan/report.c:412
	 strlen+0x8e/0xa0 lib/string.c:482
	 kstrdup+0x21/0x70 mm/util.c:55
	 alloc_trace_kprobe+0xc8/0x930 kernel/trace/trace_kprobe.c:325
	 create_local_trace_kprobe+0x4f/0x3a0 kernel/trace/trace_kprobe.c:1438
	 perf_kprobe_init+0x149/0x1f0 kernel/trace/trace_event_perf.c:264
	 perf_kprobe_event_init+0xa8/0x120 kernel/events/core.c:8407
	 perf_try_init_event+0xcb/0x2a0 kernel/events/core.c:9719
	 perf_init_event kernel/events/core.c:9750 [inline]
	 perf_event_alloc+0x1367/0x1e20 kernel/events/core.c:10022
	 SYSC_perf_event_open+0x242/0x2330 kernel/events/core.c:10477
	 do_syscall_64+0x198/0x640 arch/x86/entry/common.c:287
	 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Reported-by: 范龙飞 <long7573@126.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: e12f03d703 ("perf/core: Implement the 'perf_kprobe' PMU")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-10 07:33:10 +02:00
Steven Rostedt (VMware) 8ec8405f08 tracing: Add rcu dereference annotation for test func that touches filter->prog
A boot up test function update_pred_fn() dereferences filter->prog without
the proper rcu annotation.

To do this, we must also take the event_mutex first. Normally, this isn't
needed because this test function can not race with other use cases that
touch the event filters (it is disabled if any events are enabled).

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Fixes: 80765597bc ("tracing: Rewrite filter logic to be simpler and faster")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:54 -04:00
Steven Rostedt (VMware) 1f3b0faa3e tracing: Add rcu dereference annotation for filter->prog
ftrace_function_set_filter() referenences filter->prog without annotation
and sparse complains about it. It needs a rcu_dereference_protected()
wrapper.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Fixes: 80765597bc ("tracing: Rewrite filter logic to be simpler and faster")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:53 -04:00
Chris Wilson 5125eee4e6 tracing: Fixup logic inversion on setting trace_global_clock defaults
In commit 932066a15335 ("tracing: Default to using trace_global_clock if
sched_clock is unstable"), the logic for deciding to override the
default clock if unstable was reversed from the earlier posting. I was
trying to reduce the width of the message by using an early return
rather than a if-block, but reverted back to using the if-block and
accidentally left the predicate inverted.

Link: http://lkml.kernel.org/r/20180404212450.26646-1-chris@chris-wilson.co.uk

Fixes: 932066a15335 ("tracing: Default to using trace_global_clock if sched_clock is unstable")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:53 -04:00
Steven Rostedt (VMware) f7a1570da9 tracing: Hide global trace clock from lockdep
Function tracing can trace in NMIs and such. If the TSC is determined
to be unstable, the tracing clock will switch to the global clock on
boot up, unless "trace_clock" is specified on the kernel command line.

The global clock disables interrupts to access sched_clock_cpu(), and in
doing so can be done within lockdep internals (because of function
tracing and NMIs). This can trigger false lockdep splats.

The trace_clock_global() is special, best not to trace the irq logic
within it.

Link: http://lkml.kernel.org/r/20180404145015.77bde42d@gandalf.local.home

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:52 -04:00
Steven Rostedt (VMware) 927e56db62 ring-buffer: Add set/clear_current_oom_origin() during allocations
As si_mem_available() can say there is enough memory even though the memory
available is not useable by the ring buffer, it is best to not kill innocent
applications because the ring buffer is taking up all the memory while it is
trying to allocate a great deal of memory.

If the allocator is user space (because kernel threads can also increase the
size of the kernel ring buffer on boot up), then after si_mem_available()
says there is enough memory, set the OOM killer to kill the current task if
an OOM triggers during the allocation.

Link: http://lkml.kernel.org/r/20180404062340.GD6312@dhcp22.suse.cz

Suggested-by: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:52 -04:00
Steven Rostedt (VMware) 2a872fa4e9 ring-buffer: Check if memory is available before allocation
The ring buffer is made up of a link list of pages. When making the ring
buffer bigger, it will allocate all the pages it needs before adding to the
ring buffer, and if it fails, it frees them and returns an error. This makes
increasing the ring buffer size an all or nothing action. When this was
first created, the pages were allocated with "NORETRY". This was to not
cause any Out-Of-Memory (OOM) actions from allocating the ring buffer. But
NORETRY was too strict, as the ring buffer would fail to expand even when
there's memory available, but was taken up in the page cache.

Commit 848618857d ("tracing/ring_buffer: Try harder to allocate") changed
the allocating from NORETRY to RETRY_MAYFAIL. The RETRY_MAYFAIL would
allocate from the page cache, but if there was no memory available, it would
simple fail the allocation and not trigger an OOM.

This worked fine, but had one problem. As the ring buffer would allocate one
page at a time, it could take up all memory in the system before it failed
to allocate and free that memory. If the allocation is happening and the
ring buffer allocates all memory and then tries to take more than available,
its allocation will not trigger an OOM, but if there's any allocation that
happens someplace else, that could trigger an OOM, even though once the ring
buffer's allocation fails, it would free up all the previous memory it tried
to allocate, and allow other memory allocations to succeed.

Commit d02bd27bd3 ("mm/page_alloc.c: calculate 'available' memory in a
separate function") separated out si_mem_availble() as a separate function
that could be used to see how much memory is available in the system. Using
this function to make sure that the ring buffer could be allocated before it
tries to allocate pages we can avoid allocating all memory in the system and
making it vulnerable to OOMs if other allocations are taking place.

Link: http://lkml.kernel.org/r/1522320104-6573-1-git-send-email-zhaoyang.huang@spreadtrum.com

CC: stable@vger.kernel.org
Cc: linux-mm@kvack.org
Fixes: 848618857d ("tracing/ring_buffer: Try harder to allocate")
Requires: d02bd27bd3 ("mm/page_alloc.c: calculate 'available' memory in a separate function")
Reported-by: Zhaoyang Huang <huangzhaoyang@gmail.com>
Tested-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:52 -04:00
Dan Carpenter b28d7b2dc2 tracing: Uninitialized variable in create_tracing_map_fields()
Smatch complains that idx can be used uninitialized when we check if
(idx < 0).  It has to be the first iteration through the loop and the
HIST_FIELD_FL_STACKTRACE bit has to be clear and the HIST_FIELD_FL_VAR
bit has to be set to reach the bug.

Link: http://lkml.kernel.org/r/20180328114815.GC29050@mwanda

Fixes: 30350d65ac ("tracing: Add variable support to hist triggers")
Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:50 -04:00
Tom Zanussi ad452870c6 tracing: Make sure variable string fields are NULL-terminated
The strncpy() currently being used for variable string fields can
result in a lack of termination if the string length is equal to the
field size.  Use the safer strscpy() instead, which will guarantee
termination.

Link: http://lkml.kernel.org/r/fb97c1e518fb358c12a4057d7445ba2c46956cd7.1522256721.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:50 -04:00
Tom Zanussi 48f794731e tracing: Add action comparisons when testing matching hist triggers
Actions also need to be considered when checking for matching triggers
- triggers differing only by action should be allowed, but currently
aren't because the matching check ignores the action and erroneously
returns -EEXIST.

Add and call an actions_match() function to address that.

Here's an example using onmatch() actions.  The first -EEXIST shouldn't
occur because the onmatch() is different in the second wakeup_latency()
param.  The second -EEXIST shouldn't occur because it's a different
action (in this case, it doesn't have an action, so shouldn't be seen
as being the same and therefore rejected).

In the after case, both are correctly accepted (and trying to add one of
them again returns -EEXIST as it should).

before:

  # echo 'wakeup_latency u64 lat; pid_t pid' >> /sys/kernel/debug/tracing/synthetic_events
  # echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
  # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0 if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
  # echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,next_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
  # echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,prev_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
-su: echo: write error: File exists
  # echo 'hist:keys=next_pid if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
-su: echo: write error: File exists

after:

  # echo 'wakeup_latency u64 lat; pid_t pid' >> /sys/kernel/debug/tracing/synthetic_events
  # echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
  # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0 if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
  # echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,next_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
  # echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,prev_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
  # echo 'hist:keys=next_pid if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger

Link: http://lkml.kernel.org/r/a7fd668b87ec10736c8f016ac4279c8480d50c2b.1522256721.git.tom.zanussi@linux.intel.com

Tested-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:49 -04:00
Tom Zanussi 76690945f5 tracing: Don't add flag strings when displaying variable references
Variable references should never have flags appended when displayed -
prevent that from happening.

Before:

  # cat /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
  hist:keys=next_pid:vals=hitcount:wakeup_lat=common_timestamp.usecs-$ts0.usecs:...

After:

  hist:keys=next_pid:vals=hitcount:wakeup_lat=common_timestamp.usecs-$ts0:...

Link: http://lkml.kernel.org/r/913318a5610ef6b24af2522575f671fa6ee19b6b.1522256721.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:49 -04:00
Tom Zanussi 0ae7961e75 tracing: Fix display of hist trigger expressions containing timestamps
When displaying hist triggers, variable references that have the
timestamp field flag set are erroneously displayed as common_timestamp
rather than the variable reference.  Additionally, timestamp
expressions are displayed in the same way.  Fix this by forcing the
timestamp flag handling to follow variable reference and expression
handling.

Before:

  # cat /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
  hist:keys=next_pid:vals=hitcount:wakeup_lat=common_timestamp.usecs:...

After:

  # cat /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
  hist:keys=next_pid:vals=hitcount:wakeup_lat=common_timestamp.usecs-$ts0.usecs:...

Link: http://lkml.kernel.org/r/92746b06be67499c2a6217bd55395b350ad18fad.1522256721.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:48 -04:00
Salvatore Mesoraca 419e9fe53b ftrace: Drop a VLA in module_exists()
Avoid a VLA by using a real constant expression instead of a variable.
The compiler should be able to optimize the original code and avoid using
an actual VLA. Anyway this change is useful because it will avoid a false
positive with -Wvla, it might also help the compiler generating better
code.

Link: http://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
Link: http://lkml.kernel.org/r/1522399988-8815-1-git-send-email-s.mesoraca16@gmail.com

Signed-off-by: Salvatore Mesoraca <s.mesoraca16@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:48 -04:00
Chris Wilson 913ea4d0b1 tracing: Mention trace_clock=global when warning about unstable clocks
Mention the alternative of adding trace_clock=global to the kernel
command line when we detect that we've used an unstable clock across a
suspend/resume cycle.

Link: http://lkml.kernel.org/r/20180330150132.16903-2-chris@chris-wilson.co.uk

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:47 -04:00
Chris Wilson 3fd49c9e48 tracing: Default to using trace_global_clock if sched_clock is unstable
Across suspend, we may see a very large drift in timestamps if the sched
clock is unstable, prompting the global trace's ringbuffer code to warn
and suggest switching to the global clock. Preempt this request by
detecting when the sched clock is unstable (determined during
late_initcall) and automatically switching the default clock over to
trace_global_clock.

This should prevent requiring user interaction to resolve warnings such
as:

    Delta way too big! 18446743856563626466 ts=18446744054496180323 write stamp = 197932553857
    If you just came from a suspend/resume,
    please switch to the trace global clock:
    echo global > /sys/kernel/debug/tracing/trace_clock

Link: http://lkml.kernel.org/r/20180330150132.16903-1-chris@chris-wilson.co.uk

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:47 -04:00
Linus Torvalds 672a9c1069 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
  kfifo: fix inaccurate comment
  tools/thermal: tmon: fix for segfault
  net: Spelling s/stucture/structure/
  edd: don't spam log if no EDD information is present
  Documentation: Fix early-microcode.txt references after file rename
  tracing: Block comments should align the * on each line
  treewide: Fix typos in printk
  GenWQE: Fix a typo in two comments
  treewide: Align function definition open/close braces
2018-04-05 11:56:35 -07:00
Linus Torvalds 680014d6d1 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull time(r) updates from Thomas Gleixner:
 "A small set of updates for timers and timekeeping:

   - The most interesting change is the consolidation of clock MONOTONIC
     and clock BOOTTIME.

     Clock MONOTONIC behaves now exactly like clock BOOTTIME and does
     not longer ignore the time spent in suspend. A new clock
     MONOTONIC_ACTIVE is provived which behaves like clock MONOTONIC in
     kernels before this change. This allows applications to
     programmatically check for the clock MONOTONIC behaviour.

     As discussed in the review thread, this has the potential of
     breaking user space and we might have to revert this. Knock on wood
     that we can avoid that exercise.

   - Updates to the NTP mechanism to improve accuracy

   - A new kernel internal data structure to aid the ongoing Y2038 work.

   - Cleanups and simplifications of the clocksource code.

   - Make the alarmtimer code play nicely with debugobjects"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  alarmtimer: Init nanosleep alarm timer on stack
  y2038: Introduce struct __kernel_old_timeval
  tracing: Unify the "boot" and "mono" tracing clocks
  hrtimer: Unify MONOTONIC and BOOTTIME clock behavior
  posix-timers: Unify MONOTONIC and BOOTTIME clock behavior
  timekeeping: Remove boot time specific code
  Input: Evdev - unify MONOTONIC and BOOTTIME clock behavior
  timekeeping: Make the MONOTONIC clock behave like the BOOTTIME clock
  timekeeping: Add the new CLOCK_MONOTONIC_ACTIVE clock
  timekeeping/ntp: Determine the multiplier directly from NTP tick length
  timekeeping/ntp: Don't align NTP frequency adjustments to ticks
  clocksource: Use ATTRIBUTE_GROUPS
  clocksource: Use DEVICE_ATTR_RW/RO/WO to define device attributes
  clocksource: Don't walk the clocksource list for empty override
2018-04-04 14:50:29 -07:00
Linus Torvalds 5bb053bef8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) Support offloading wireless authentication to userspace via
    NL80211_CMD_EXTERNAL_AUTH, from Srinivas Dasari.

 2) A lot of work on network namespace setup/teardown from Kirill Tkhai.
    Setup and cleanup of namespaces now all run asynchronously and thus
    performance is significantly increased.

 3) Add rx/tx timestamping support to mv88e6xxx driver, from Brandon
    Streiff.

 4) Support zerocopy on RDS sockets, from Sowmini Varadhan.

 5) Use denser instruction encoding in x86 eBPF JIT, from Daniel
    Borkmann.

 6) Support hw offload of vlan filtering in mvpp2 dreiver, from Maxime
    Chevallier.

 7) Support grafting of child qdiscs in mlxsw driver, from Nogah
    Frankel.

 8) Add packet forwarding tests to selftests, from Ido Schimmel.

 9) Deal with sub-optimal GSO packets better in BBR congestion control,
    from Eric Dumazet.

10) Support 5-tuple hashing in ipv6 multipath routing, from David Ahern.

11) Add path MTU tests to selftests, from Stefano Brivio.

12) Various bits of IPSEC offloading support for mlx5, from Aviad
    Yehezkel, Yossi Kuperman, and Saeed Mahameed.

13) Support RSS spreading on ntuple filters in SFC driver, from Edward
    Cree.

14) Lots of sockmap work from John Fastabend. Applications can use eBPF
    to filter sendmsg and sendpage operations.

15) In-kernel receive TLS support, from Dave Watson.

16) Add XDP support to ixgbevf, this is significant because it should
    allow optimized XDP usage in various cloud environments. From Tony
    Nguyen.

17) Add new Intel E800 series "ice" ethernet driver, from Anirudh
    Venkataramanan et al.

18) IP fragmentation match offload support in nfp driver, from Pieter
    Jansen van Vuuren.

19) Support XDP redirect in i40e driver, from Björn Töpel.

20) Add BPF_RAW_TRACEPOINT program type for accessing the arguments of
    tracepoints in their raw form, from Alexei Starovoitov.

21) Lots of striding RQ improvements to mlx5 driver with many
    performance improvements, from Tariq Toukan.

22) Use rhashtable for inet frag reassembly, from Eric Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1678 commits)
  net: mvneta: improve suspend/resume
  net: mvneta: split rxq/txq init and txq deinit into SW and HW parts
  ipv6: frags: fix /proc/sys/net/ipv6/ip6frag_low_thresh
  net: bgmac: Fix endian access in bgmac_dma_tx_ring_free()
  net: bgmac: Correctly annotate register space
  route: check sysctl_fib_multipath_use_neigh earlier than hash
  fix typo in command value in drivers/net/phy/mdio-bitbang.
  sky2: Increase D3 delay to sky2 stops working after suspend
  net/mlx5e: Set EQE based as default TX interrupt moderation mode
  ibmvnic: Disable irqs before exiting reset from closed state
  net: sched: do not emit messages while holding spinlock
  vlan: also check phy_driver ts_info for vlan's real device
  Bluetooth: Mark expected switch fall-throughs
  Bluetooth: Set HCI_QUIRK_SIMULTANEOUS_DISCOVERY for BTUSB_QCA_ROME
  Bluetooth: btrsi: remove unused including <linux/version.h>
  Bluetooth: hci_bcm: Remove DMI quirk for the MINIX Z83-4
  sh_eth: kill useless check in __sh_eth_get_regs()
  sh_eth: add sh_eth_cpu_data::no_xdfar flag
  ipv6: factorize sk_wmem_alloc updates done by __ip6_append_data()
  ipv4: factorize sk_wmem_alloc updates done by __ip_append_data()
  ...
2018-04-03 14:04:18 -07:00
David S. Miller c0b458a946 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Minor conflicts in drivers/net/ethernet/mellanox/mlx5/core/en_rep.c,
we had some overlapping changes:

1) In 'net' MLX5E_PARAMS_LOG_{SQ,RQ}_SIZE -->
   MLX5E_REP_PARAMS_LOG_{SQ,RQ}_SIZE

2) In 'net-next' params->log_rq_size is renamed to be
   params->log_rq_mtu_frames.

3) In 'net-next' params->hard_mtu is added.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-01 19:49:34 -04:00
Andrey Ignatov 5e43f899b0 bpf: Check attach type at prog load time
== The problem ==

There are use-cases when a program of some type can be attached to
multiple attach points and those attach points must have different
permissions to access context or to call helpers.

E.g. context structure may have fields for both IPv4 and IPv6 but it
doesn't make sense to read from / write to IPv6 field when attach point
is somewhere in IPv4 stack.

Same applies to BPF-helpers: it may make sense to call some helper from
some attach point, but not from other for same prog type.

== The solution ==

Introduce `expected_attach_type` field in in `struct bpf_attr` for
`BPF_PROG_LOAD` command. If scenario described in "The problem" section
is the case for some prog type, the field will be checked twice:

1) At load time prog type is checked to see if attach type for it must
   be known to validate program permissions correctly. Prog will be
   rejected with EINVAL if it's the case and `expected_attach_type` is
   not specified or has invalid value.

2) At attach time `attach_type` is compared with `expected_attach_type`,
   if prog type requires to have one, and, if they differ, attach will
   be rejected with EINVAL.

The `expected_attach_type` is now available as part of `struct bpf_prog`
in both `bpf_verifier_ops->is_valid_access()` and
`bpf_verifier_ops->get_func_proto()` () and can be used to check context
accesses and calls to helpers correspondingly.

Initially the idea was discussed by Alexei Starovoitov <ast@fb.com> and
Daniel Borkmann <daniel@iogearbox.net> here:
https://marc.info/?l=linux-netdev&m=152107378717201&w=2

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-31 02:14:44 +02:00
Ingo Molnar 2d074918fb Merge branch 'perf/urgent' into perf/core
Conflicts:
	kernel/events/hw_breakpoint.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-29 16:03:48 +02:00
Alexei Starovoitov c4f6699dfc bpf: introduce BPF_RAW_TRACEPOINT
Introduce BPF_PROG_TYPE_RAW_TRACEPOINT bpf program type to access
kernel internal arguments of the tracepoints in their raw form.

>From bpf program point of view the access to the arguments look like:
struct bpf_raw_tracepoint_args {
       __u64 args[0];
};

int bpf_prog(struct bpf_raw_tracepoint_args *ctx)
{
  // program can read args[N] where N depends on tracepoint
  // and statically verified at program load+attach time
}

kprobe+bpf infrastructure allows programs access function arguments.
This feature allows programs access raw tracepoint arguments.

Similar to proposed 'dynamic ftrace events' there are no abi guarantees
to what the tracepoints arguments are and what their meaning is.
The program needs to type cast args properly and use bpf_probe_read()
helper to access struct fields when argument is a pointer.

For every tracepoint __bpf_trace_##call function is prepared.
In assembler it looks like:
(gdb) disassemble __bpf_trace_xdp_exception
Dump of assembler code for function __bpf_trace_xdp_exception:
   0xffffffff81132080 <+0>:     mov    %ecx,%ecx
   0xffffffff81132082 <+2>:     jmpq   0xffffffff811231f0 <bpf_trace_run3>

where

TRACE_EVENT(xdp_exception,
        TP_PROTO(const struct net_device *dev,
                 const struct bpf_prog *xdp, u32 act),

The above assembler snippet is casting 32-bit 'act' field into 'u64'
to pass into bpf_trace_run3(), while 'dev' and 'xdp' args are passed as-is.
All of ~500 of __bpf_trace_*() functions are only 5-10 byte long
and in total this approach adds 7k bytes to .text.

This approach gives the lowest possible overhead
while calling trace_xdp_exception() from kernel C code and
transitioning into bpf land.
Since tracepoint+bpf are used at speeds of 1M+ events per second
this is valuable optimization.

The new BPF_RAW_TRACEPOINT_OPEN sys_bpf command is introduced
that returns anon_inode FD of 'bpf-raw-tracepoint' object.

The user space looks like:
// load bpf prog with BPF_PROG_TYPE_RAW_TRACEPOINT type
prog_fd = bpf_prog_load(...);
// receive anon_inode fd for given bpf_raw_tracepoint with prog attached
raw_tp_fd = bpf_raw_tracepoint_open("xdp_exception", prog_fd);

Ctrl-C of tracing daemon or cmdline tool that uses this feature
will automatically detach bpf program, unload it and
unregister tracepoint probe.

On the kernel side the __bpf_raw_tp_map section of pointers to
tracepoint definition and to __bpf_trace_*() probe function is used
to find a tracepoint with "xdp_exception" name and
corresponding __bpf_trace_xdp_exception() probe function
which are passed to tracepoint_probe_register() to connect probe
with tracepoint.

Addition of bpf_raw_tracepoint doesn't interfere with ftrace and perf
tracepoint mechanisms. perf_event_open() can be used in parallel
on the same tracepoint.
Multiple bpf_raw_tracepoint_open("xdp_exception", prog_fd) are permitted.
Each with its own bpf program. The kernel will execute
all tracepoint probes and all attached bpf programs.

In the future bpf_raw_tracepoints can be extended with
query/introspection logic.

__bpf_raw_tp_map section logic was contributed by Steven Rostedt

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-28 22:55:19 +02:00
Rohit Visavalia 13cf912b2d tracing: Block comments should align the * on each line
Resolved Block comments use * on subsequent lines checkpatch warning.
Issue found by checkpatch.

Signed-off-by: Rohit Visavalia <rohit.visavalia@softnautics.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2018-03-27 09:51:23 +02:00
Joe Perches 447a5647c9 treewide: Align function definition open/close braces
Some functions definitions have either the initial open brace and/or
the closing brace outside of column 1.

Move those braces to column 1.

This allows various function analyzers like gnu complexity to work
properly for these modified functions.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Nicolin Chen <nicoleotsuka@gmail.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2018-03-26 11:13:09 +02:00
Linus Torvalds 99fec39e77 The documentation for kprobe events says that symbol offets can
take both a + and - sign to get to befor and after the symbol address.
 But in actuality, the code does not support the minus. This fixes
 that issue, and adds a few more selftests to kprobe events.
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Merge tag 'trace-v4.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull kprobe fixes from Steven Rostedt:
 "The documentation for kprobe events says that symbol offets can take
  both a + and - sign to get to befor and after the symbol address.

  But in actuality, the code does not support the minus. This fixes that
  issue, and adds a few more selftests to kprobe events"

* tag 'trace-v4.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  selftests: ftrace: Add a testcase for probepoint
  selftests: ftrace: Add a testcase for string type with kprobe_event
  selftests: ftrace: Add probe event argument syntax testcase
  tracing: probeevent: Fix to support minus offset from symbol
2018-03-23 15:34:18 -07:00
Masami Hiramatsu c5d343b6b7 tracing: probeevent: Fix to support minus offset from symbol
In Documentation/trace/kprobetrace.txt, it says

 @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol)

However, the parser doesn't parse minus offset correctly, since
commit 2fba0c8867 ("tracing/kprobes: Fix probe offset to be
unsigned") drops minus ("-") offset support for kprobe probe
address usage.

This fixes the traceprobe_split_symbol_offset() to parse minus
offset again with checking the offset range, and add a minus
offset check in kprobe probe address usage.

Link: http://lkml.kernel.org/r/152129028983.31874.13419301530285775521.stgit@devbox

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Fixes: 2fba0c8867 ("tracing/kprobes: Fix probe offset to be unsigned")
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-23 12:02:37 -04:00
David S. Miller 03fe2debbb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Fun set of conflict resolutions here...

For the mac80211 stuff, these were fortunately just parallel
adds.  Trivially resolved.

In drivers/net/phy/phy.c we had a bug fix in 'net' that moved the
function phy_disable_interrupts() earlier in the file, whilst in
'net-next' the phy_error() call from this function was removed.

In net/ipv4/xfrm4_policy.c, David Ahern's changes to remove the
'rt_table_id' member of rtable collided with a bug fix in 'net' that
added a new struct member "rt_mtu_locked" which needs to be copied
over here.

The mlxsw driver conflict consisted of net-next separating
the span code and definitions into separate files, whilst
a 'net' bug fix made some changes to that moved code.

The mlx5 infiniband conflict resolution was quite non-trivial,
the RDMA tree's merge commit was used as a guide here, and
here are their notes:

====================

    Due to bug fixes found by the syzkaller bot and taken into the for-rc
    branch after development for the 4.17 merge window had already started
    being taken into the for-next branch, there were fairly non-trivial
    merge issues that would need to be resolved between the for-rc branch
    and the for-next branch.  This merge resolves those conflicts and
    provides a unified base upon which ongoing development for 4.17 can
    be based.

    Conflicts:
            drivers/infiniband/hw/mlx5/main.c - Commit 42cea83f95
            (IB/mlx5: Fix cleanup order on unload) added to for-rc and
            commit b5ca15ad7e (IB/mlx5: Add proper representors support)
            add as part of the devel cycle both needed to modify the
            init/de-init functions used by mlx5.  To support the new
            representors, the new functions added by the cleanup patch
            needed to be made non-static, and the init/de-init list
            added by the representors patch needed to be modified to
            match the init/de-init list changes made by the cleanup
            patch.
    Updates:
            drivers/infiniband/hw/mlx5/mlx5_ib.h - Update function
            prototypes added by representors patch to reflect new function
            names as changed by cleanup patch
            drivers/infiniband/hw/mlx5/ib_rep.c - Update init/de-init
            stage list to match new order from cleanup patch
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-23 11:31:58 -04:00
Dan Carpenter 5e4cf2bf6d tracing: Fix a potential NULL dereference
We forgot to set the error code on this path so we return ERR_PTR(0)
which is NULL.  It results in a NULL dereference in the caller.

Link: http://lkml.kernel.org/r/20180323113735.GC28518@mwanda

Fixes: 100719dcef ("tracing: Add simple expression support to hist triggers")
Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-23 11:15:20 -04:00
Yonghong Song f005afede9 trace/bpf: remove helper bpf_perf_prog_read_value from tracepoint type programs
Commit 4bebdc7a85 ("bpf: add helper bpf_perf_prog_read_value")
added helper bpf_perf_prog_read_value so that perf_event type program
can read event counter and enabled/running time.
This commit, however, introduced a bug which allows this helper
for tracepoint type programs. This is incorrect as bpf_perf_prog_read_value
needs to access perf_event through its bpf_perf_event_data_kern type context,
which is not available for tracepoint type program.

This patch fixed the issue by separating bpf_func_proto between tracepoint
and perf_event type programs and removed bpf_perf_prog_read_value
from tracepoint func prototype.

Fixes: 4bebdc7a85 ("bpf: add helper bpf_perf_prog_read_value")
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-20 23:08:52 +01:00
Steven Rostedt (VMware) 80765597bc tracing: Rewrite filter logic to be simpler and faster
Al Viro reviewed the filter logic of ftrace trace events and found it to be
very troubling. It creates a binary tree based on the logic operators and
walks it during tracing. He sent myself and Tom Zanussi a long explanation
(and formal proof) of how to do the string parsing better and end up with a
program array that can be simply iterated to come up with the correct
results.

I took his ideas and his pseudo code and rewrote the filter logic based on
them. In doing so, I was able to remove a lot of code, and have a much more
condensed filter logic in the process. I wrote a very long comment
describing the methadology that Al proposed in my own words. For more info
on how this works, read the comment above predicate_parse().

Suggested-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-14 12:35:39 -04:00
Steven Rostedt (VMware) 478325f188 tracing: Clean up and document pred_funcs_##type creation and use
The pred_funcs_##type arrays consist of five functions that are assigned
based on the ops. The array must be in the same order of the ops each
function represents. The PRED_FUNC_START macro denotes the op enum that
starts the op that maps to the pred_funcs_##type arrays. This is all very
subtle and prone to bugs if the code is changed.

Add comments describing how PRED_FUNC_START and pred_funcs_##type array is
used, and also a PRED_FUNC_MAX that is the maximum number of functions in
the arrays.

Clean up select_comparison_fn() that assigns the predicates to the
pred_funcs_##type array function as well as add protection in case an op is
passed in that does not map correctly to the array.

Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-14 12:35:20 -04:00
Steven Rostedt (VMware) e9baef0d86 tracing: Combine enum and arrays into single macro in filter code
Instead of having a separate enum that is the index into another array, like
a string array, make a single macro that combines them into a single list,
and then the two can not get out of sync. This makes it easier to add and
remove items.

The macro trick is:

 #define DOGS				\
  C( JACK,     "Jack Russell")		\
  C( ITALIAN,  "Italian Greyhound")	\
  C( GERMAN,   "German Shepherd")

 #undef C
 #define C(a, b) a

 enum { DOGS };

 #undef C
 #define C(a, b) b

 static char dogs[] = { DOGS };

Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-14 12:32:18 -04:00
Thomas Gleixner 92af4dcb4e tracing: Unify the "boot" and "mono" tracing clocks
Unify the "boot" and "mono" tracing clocks and document the new behaviour.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kevin Easton <kevin@guarana.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Salyzyn <salyzyn@android.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20180301165150.489635255@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-13 07:34:23 +01:00
Steven Rostedt (VMware) 567f6989fd tracing: Embed replace_filter_string() helper function
The replace_filter_string() frees the current string and then copies a given
string. But in the two locations that it was used, the allocation happened
right after the filter was allocated (nothing to replace). There's no need
for this to be a helper function. Embedding the allocation in the two places
where it was called will make changing the code in the future easier.

Also make the variable consistent (always use "filter_string" as the name,
as it was used in one instance as "filter_str")

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:07 -05:00
Steven Rostedt (VMware) 404a3add43 tracing: Only add filter list when needed
replace_system_preds() creates a filter list to free even when it doesn't
really need to have it. Only save filters that require synchronize_sched()
in the filter list to free. This will allow the code to be updated a bit
easier in the future.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:07 -05:00
Steven Rostedt (VMware) c7399708b3 tracing: Remove filter allocator helper
The __alloc_filter() function does nothing more that allocate the filter.
There's no reason to have it as a helper function.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:06 -05:00
Steven Rostedt (VMware) 559d421267 tracing: Use trace_seq instead of open code string appending
The filter code does open code string appending to produce an error message.
Instead it can be simplified by using trace_seq function helpers.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:06 -05:00
Steven Rostedt (VMware) a0ff08fd4e tracing: Remove BUG_ON() from append_filter_string()
There's no reason to BUG if there's a bug in the filtering code. Simply do a
warning and return.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:05 -05:00
Tom Zanussi 89e270c1df tracing: Add inter-event blurb to HIST_TRIGGERS config option
So that users know that inter-event tracing is supported as part of
the HIST_TRIGGERS option, include text to that effect in the help
text.

Link: http://lkml.kernel.org/r/a38e24231d8d980be636b56d35814570acfd167a.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:05 -05:00
Steven Rostedt (VMware) 4708abc6c6 tracing: Use the ring-buffer nesting to allow synthetic events to be traced
Synthetic events can be done within the recording of other events. Notify
the ring buffer via ring_buffer_nest_start() and ring_buffer_nest_end() that
this is intended and not to block it due to its recursion protection.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:04 -05:00
Steven Rostedt (VMware) 8e012066fe ring-buffer: Add nesting for adding events within events
The ring-buffer code has recusion protection in case tracing ends up tracing
itself, the ring-buffer will detect that it was called at the same context
(normal, softirq, interrupt or NMI), and not continue to record the event.

With the histogram synthetic events, they are called while tracing another
event at the same context. The recusion protection triggers because it
detects tracing at the same context and stops it.

Add ring_buffer_nest_start() and ring_buffer_nest_end() that will notify the
ring buffer that a trace is about to happen within another trace and that it
is intended, and not to trigger the recursion blocking.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:04 -05:00
Tom Zanussi a4072fe85b tracing: Add a clock attribute for hist triggers
The default clock if timestamps are used in a histogram is "global".
If timestamps aren't used, the clock is irrelevant.

Use the "clock=" param only if you want to override the default
"global" clock for a histogram with timestamps.

Link: http://lkml.kernel.org/r/427bed1389c5d22aa40c3e0683e30cc3d151e260.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Rajvi Jingar <rajvi.jingar@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:03 -05:00
Tom Zanussi d71bd34d78 tracing: Make tracing_set_clock() non-static
Allow tracing code outside of trace.c to access tracing_set_clock().

Some applications may require a particular clock in order to function
properly, such as latency calculations.

Also, add an accessor returning the current clock string.

Link: http://lkml.kernel.org/r/6d1c53e9ee2163f54e1849f5376573f54f0e6009.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:03 -05:00
Tom Zanussi f404da6e1d tracing: Add 'last error' error facility for hist triggers
With the addition of variables and actions, it's become necessary to
provide more detailed error information to users about syntax errors.

Add a 'last error' facility accessible via the erroring event's 'hist'
file.  Reading the hist file after an error will display more detailed
information about what went wrong, if information is available.  This
extended error information will be available until the next hist
trigger command for that event.

  # echo xxx > /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
  echo: write error: Invalid argument

  # cat /sys/kernel/debug/tracing/events/sched/sched_wakeup/hist

  ERROR: Couldn't yyy: zzz
  Last command: xxx

Also add specific error messages for variable and action errors.

Link: http://lkml.kernel.org/r/64e9c422fc8aeafcc2f7a3b4328c0cffe7969129.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:02 -05:00
Tom Zanussi 7e8b88a30b tracing: Add hist trigger support for variable reference aliases
Add support for alias=$somevar where alias can be used as
onmatch.xxx($alias).

Aliases are a way of creating a new name for an existing variable, for
flexibly in making naming more clear in certain cases.  For example in
the below the user perhaps feels that using $new_lat in the synthetic
event invocation is opaque or doesn't fit well stylistically with
previous triggers, so creates an alias of $new_lat named $latency and
uses that in the call instead:

  # echo 'hist:keys=next_pid:new_lat=common_timestamp.usecs' >
    /sys/kernel/debug/tracing/events/sched/sched_switch/trigger

  # echo 'hist:keys=pid:latency=$new_lat:
    onmatch(sched.sched_switch).wake2($latency,pid)' >
    /sys/kernel/debug/tracing/events/synthetic/wake1/trigger

Link: http://lkml.kernel.org/r/ef20a65d921af3a873a6f1e8c71407c926d5586f.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:01 -05:00
Tom Zanussi 8b7622bf94 tracing: Add cpu field for hist triggers
A common key to use in a histogram is the cpuid - add a new cpu
'synthetic' field named 'cpu' for that purpose.

Link: http://lkml.kernel.org/r/89537645bfc957e0d76e2cacf5f0ada88691a6cc.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:01 -05:00
Tom Zanussi ec5ce09875 tracing: Allow whitespace to surround hist trigger filter
The existing code only allows for one space before and after the 'if'
specifying the filter for a hist trigger.  Add code to make that more
permissive as far as whitespace goes.  Specifically, we want to allow
spaces in the trigger itself now that we have additional syntax
(onmatch/onmax) where spaces are more natural e.g. spaces after commas
in param lists.

Link: http://lkml.kernel.org/r/1053090c3c308d4f431accdeb59dff4b511d4554.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:00 -05:00
Tom Zanussi 50450603ec tracing: Add 'onmax' hist trigger action support
Add an 'onmax(var).save(field,...)' hist trigger action which is
invoked whenever an event exceeds the current maximum.

The end result is that the trace event fields or variables specified
as the onmax.save() params will be saved if 'var' exceeds the current
maximum for that hist trigger entry.  This allows context from the
event that exhibited the new maximum to be saved for later reference.
When the histogram is displayed, additional fields displaying the
saved values will be printed.

As an example the below defines a couple of hist triggers, one for
sched_wakeup and another for sched_switch, keyed on pid.  Whenever a
sched_wakeup occurs, the timestamp is saved in the entry corresponding
to the current pid, and when the scheduler switches back to that pid,
the timestamp difference is calculated.  If the resulting latency
exceeds the current maximum latency, the specified save() values are
saved:

    # echo 'hist:keys=pid:ts0=common_timestamp.usecs \
        if comm=="cyclictest"' >> \
      /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger

    # echo 'hist:keys=next_pid:\
      wakeup_lat=common_timestamp.usecs-$ts0:\
      onmax($wakeup_lat).save(next_comm,prev_pid,prev_prio,prev_comm) \
        if next_comm=="cyclictest"' >> \
      /sys/kernel/debug/tracing/events/sched/sched_switch/trigger

When the histogram is displayed, the max value and the saved values
corresponding to the max are displayed following the rest of the
fields:

    # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist

      { next_pid:       3728 } hitcount:        199 \
        max:        123  next_comm: cyclictest  prev_pid:          0 \
	prev_prio:        120  prev_comm: swapper/3
      { next_pid:       3730 } hitcount:       1321 \
        max:         15  next_comm: cyclictest  prev_pid:          0 \
	prev_prio:        120  prev_comm: swapper/1
      { next_pid:       3729 } hitcount:       1973\
        max:         25  next_comm: cyclictest  prev_pid:          0  \
	prev_prio:        120  prev_comm: swapper/0

    Totals:
        Hits: 3493
        Entries: 3
	Dropped: 0

Link: http://lkml.kernel.org/r/006907f71b1e839bb059337ec3c496f84fcb71de.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:00 -05:00
Tom Zanussi c282a386a3 tracing: Add 'onmatch' hist trigger action support
Add an 'onmatch(matching.event).<synthetic_event_name>(param list)'
hist trigger action which is invoked with the set of variables or
event fields named in the 'param list'.  The result is the generation
of a synthetic event that consists of the values contained in those
variables and/or fields at the time the invoking event was hit.

As an example the below defines a simple synthetic event using a
variable defined on the sched_wakeup_new event, and shows the event
definition with unresolved fields, since the sched_wakeup_new event
with the testpid variable hasn't been defined yet:

    # echo 'wakeup_new_test pid_t pid; int prio' >> \
      /sys/kernel/debug/tracing/synthetic_events

    # cat /sys/kernel/debug/tracing/synthetic_events
      wakeup_new_test pid_t pid; int prio

The following hist trigger both defines a testpid variable and
specifies an onmatch() trace action that uses that variable along with
a non-variable field to generate a wakeup_new_test synthetic event
whenever a sched_wakeup_new event occurs, which because of the 'if
comm == "cyclictest"' filter only happens when the executable is
cyclictest:

    # echo 'hist:testpid=pid:keys=$testpid:\
      onmatch(sched.sched_wakeup_new).wakeup_new_test($testpid, prio) \
        if comm=="cyclictest"' >> \
      /sys/kernel/debug/tracing/events/sched/sched_wakeup_new/trigger

Creating and displaying a histogram based on those events is now just
a matter of using the fields and new synthetic event in the
tracing/events/synthetic directory, as usual:

    # echo 'hist:keys=pid,prio:sort=pid,prio' >> \
      /sys/kernel/debug/tracing/events/synthetic/wakeup_new_test/trigger

Link: http://lkml.kernel.org/r/8c2a574bcb7530c876629c901ecd23911b14afe8.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Rajvi Jingar <rajvi.jingar@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:59 -05:00
Tom Zanussi 02205a6752 tracing: Add support for 'field variables'
Users should be able to directly specify event fields in hist trigger
'actions' rather than being forced to explicitly create a variable for
that purpose.

Add support allowing fields to be used directly in actions, which
essentially does just that - creates 'invisible' variables for each
bare field specified in an action.  If a bare field refers to a field
on another (matching) event, it even creates a special histogram for
the purpose (since variables can't be defined on an existing histogram
after histogram creation).

Here's a simple example that demonstrates both.  Basically the
onmatch() action creates a list of variables corresponding to the
parameters of the synthetic event to be generated, and then uses those
values to generate the event.  So for the wakeup_latency synthetic
event 'call' below the first param, $wakeup_lat, is a variable defined
explicitly on sched_switch, where 'next_pid' is just a normal field on
sched_switch, and prio is a normal field on sched_waking.

Since the mechanism works on variables, those two normal fields just
have 'invisible' variables created internally for them.  In the case of
'prio', which is on another event, we actually need to create an
additional hist trigger and define the invisible variable on that, since
once a hist trigger is defined, variables can't be added to it later.

  echo 'wakeup_latency u64 lat; pid_t pid; int prio' >>
       /sys/kernel/debug/tracing/synthetic_events

  echo 'hist:keys=pid:ts0=common_timestamp.usecs >>
       /sys/kernel/debug/tracing/events/sched/sched_waking/trigger

echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0:
      onmatch(sched.sched_waking).wakeup_latency($wakeup_lat,next_pid,prio)
            >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger

Link: http://lkml.kernel.org/r/8e8dcdac1ea180ed7a3689e1caeeccede9dc42b3.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:59 -05:00
Tom Zanussi 4b147936fa tracing: Add support for 'synthetic' events
Synthetic events are user-defined events generated from hist trigger
variables saved from one or more other events.

To define a synthetic event, the user writes a simple specification
consisting of the name of the new event along with one or more
variables and their type(s), to the tracing/synthetic_events file.

For instance, the following creates a new event named 'wakeup_latency'
with 3 fields: lat, pid, and prio:

    # echo 'wakeup_latency u64 lat; pid_t pid; int prio' >> \
      /sys/kernel/debug/tracing/synthetic_events

Reading the tracing/synthetic_events file lists all the
currently-defined synthetic events, in this case the event we defined
above:

    # cat /sys/kernel/debug/tracing/synthetic_events
    wakeup_latency u64 lat; pid_t pid; int prio

At this point, the synthetic event is ready to use, and a histogram
can be defined using it:

    # echo 'hist:keys=pid,prio,lat.log2:sort=pid,lat' >> \
    /sys/kernel/debug/tracing/events/synthetic/wakeup_latency/trigger

The new event is created under the tracing/events/synthetic/ directory
and looks and behaves just like any other event:

    # ls /sys/kernel/debug/tracing/events/synthetic/wakeup_latency
      enable  filter  format  hist  id  trigger

Although a histogram can be defined for it, nothing will happen until
an action tracing that event via the trace_synth() function occurs.
The trace_synth() function is very similar to all the other trace_*
invocations spread throughout the kernel, except in this case the
trace_ function and its corresponding tracepoint isn't statically
generated but defined by the user at run-time.

How this can be automatically hooked up via a hist trigger 'action' is
discussed in a subsequent patch.

Link: http://lkml.kernel.org/r/c68df2284b7d172669daf9be29db62ad49bbc559.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
[fix noderef.cocci warnings, sizeof pointer for kcalloc of event->fields]
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:58 -05:00
Tom Zanussi 0212e2aa30 tracing: Add hist trigger action hook
Add a hook for executing extra actions whenever a histogram entry is
added or updated.

The default 'action' when a hist entry is added to a histogram is to
update the set of values associated with it.  Some applications may
want to perform additional actions at that point, such as generate
another event, or compare and save a maximum.

Add a simple framework for doing that; specific actions will be
implemented on top of it in later patches.

Link: http://lkml.kernel.org/r/9482ba6a3eaf5ca6e60954314beacd0e25c05b24.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:58 -05:00
Tom Zanussi 067fe038e7 tracing: Add variable reference handling to hist triggers
Add the necessary infrastructure to allow the variables defined on one
event to be referenced in another.  This allows variables set by a
previous event to be referenced and used in expressions combining the
variable values saved by that previous event and the event fields of
the current event.  For example, here's how a latency can be
calculated and saved into yet another variable named 'wakeup_lat':

    # echo 'hist:keys=pid,prio:ts0=common_timestamp ...
    # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp-$ts0 ...

In the first event, the event's timetamp is saved into the variable
ts0.  In the next line, ts0 is subtracted from the second event's
timestamp to produce the latency.

Further users of variable references will be described in subsequent
patches, such as for instance how the 'wakeup_lat' variable above can
be displayed in a latency histogram.

Link: http://lkml.kernel.org/r/b1d3e6975374e34d501ff417c20189c3f9b2c7b8.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:58 -05:00
Tom Zanussi 19a9facd0f tracing: Add hist_field 'type' field
Future support for synthetic events requires hist_field 'type'
information, so add a field for that.

Also, make other hist_field attribute usage consistent (size,
is_signed, etc).

Link: http://lkml.kernel.org/r/3fd12a2e86316b05151ba0d7c68268e780af2c9d.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:57 -05:00
Tom Zanussi df35d93bbf tracing: Pass tracing_map_elt to hist_field accessor functions
Some accessor functions, such as for variable references, require
access to a corrsponding tracing_map_elt.

Add a tracing_map_elt param to the function signature and update the
accessor functions accordingly.

Link: http://lkml.kernel.org/r/e0f292b068e9e4948da1d5af21b5ae0efa9b5717.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:57 -05:00
Tom Zanussi af6a29bcaf tracing: Generalize per-element hist trigger data
Up until now, hist triggers only needed per-element support for saving
'comm' data, which was saved directly as a private data pointer.

In anticipation of the need to save other data besides 'comm', add a
new hist_elt_data struct for the purpose, and switch the current
'comm'-related code over to that.

Link: http://lkml.kernel.org/r/4502c338c965ddf5fc19fb1ec4764391e001ed4b.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:56 -05:00
Tom Zanussi 100719dcef tracing: Add simple expression support to hist triggers
Add support for simple addition, subtraction, and unary expressions
(-(expr) and expr, where expr = b-a, a+b, a+b+c) to hist triggers, in
order to support a minimal set of useful inter-event calculations.

These operations are needed for calculating latencies between events
(timestamp1-timestamp0) and for combined latencies (latencies over 3
or more events).

In the process, factor out some common code from key and value
parsing.

Link: http://lkml.kernel.org/r/9a9308ead4fe32a433d9c7e95921fb798394f6b2.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
[kbuild test robot fix, add static to parse_atom()]
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
[ Replaced '//' comments with normal /* */ comments ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:56 -05:00
Tom Zanussi 2ece94fbd2 tracing: Move get_hist_field_flags()
Move get_hist_field_flags() to make it more easily accessible for new
code (and keep the move separate from new functionality).

Link: http://lkml.kernel.org/r/32470f0a7047ec7a6e84ba5ec89d6142cc6ede7d.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:55 -05:00
Tom Zanussi 1a361dfcf2 tracing: Account for variables in named trigger compatibility
Named triggers must also have the same set of variables in order to be
considered compatible - update the trigger match test to account for
that.

The reason for this requirement is that named triggers with variables
are meant to allow one or more events to set the same variable.

Link: http://lkml.kernel.org/r/a17eae6328a99917f9d5c66129c9fcd355279ee9.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:55 -05:00
Tom Zanussi 30350d65ac tracing: Add variable support to hist triggers
Add support for saving the value of a current event's event field by
assigning it to a variable that can be read by a subsequent event.

The basic syntax for saving a variable is to simply prefix a unique
variable name not corresponding to any keyword along with an '=' sign
to any event field.

Both keys and values can be saved and retrieved in this way:

    # echo 'hist:keys=next_pid:vals=$ts0:ts0=common_timestamp ...
    # echo 'hist:timer_pid=common_pid:key=$timer_pid ...'

If a variable isn't a key variable or prefixed with 'vals=', the
associated event field will be saved in a variable but won't be summed
as a value:

    # echo 'hist:keys=next_pid:ts1=common_timestamp:...

Multiple variables can be assigned at the same time:

    # echo 'hist:keys=pid:vals=$ts0,$b,field2:ts0=common_timestamp,b=field1 ...

Multiple (or single) variables can also be assigned at the same time
using separate assignments:

    # echo 'hist:keys=pid:vals=$ts0:ts0=common_timestamp:b=field1:c=field2 ...

Variables set as above can be used by being referenced from another
event, as described in a subsequent patch.

Link: http://lkml.kernel.org/r/fc93c4944d9719dbcb1d0067be627d44e98e2adc.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Baohong Liu <baohong.liu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:54 -05:00
Tom Zanussi 860f9f6b02 tracing: Add usecs modifier for hist trigger timestamps
Appending .usecs onto a common_timestamp field will cause the
timestamp value to be in microseconds instead of the default
nanoseconds.  A typical latency histogram using usecs would look like
this:

   # echo 'hist:keys=pid,prio:ts0=common_timestamp.usecs ...
   # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0 ...

This also adds an external trace_clock_in_ns() to trace.c for the
timestamp conversion.

Link: http://lkml.kernel.org/r/4e813705a170b3e13e97dc3135047362fb1a39f3.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:54 -05:00
Tom Zanussi b559d003a2 tracing: Add hist_data member to hist_field
Allow hist_data access via hist_field.  Some users of hist_fields
require or will require more access to the associated hist_data.

Link: http://lkml.kernel.org/r/d04cd0768f5228ebb4ac0ba4a847bc4d14d4826f.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:53 -05:00
Tom Zanussi 2734b62952 tracing: Add per-element variable support to tracing_map
In order to allow information to be passed between trace events, add
support for per-element variables to tracing_map.  This provides a
means for histograms to associate a value or values with an entry when
it's saved or updated, and retrieved by a subsequent event occurrences.

Variables can be set using tracing_map_set_var() and read using
tracing_map_read_var().  tracing_map_var_set() returns true or false
depending on whether or not the variable has been set or not, which is
important for event-matching applications.

tracing_map_read_var_once() reads the variable and resets it to the
'unset' state, implementing read-once variables, which are also
important for event-matching uses.

Link: http://lkml.kernel.org/r/7fa001108252556f0c6dd9d63145eabfe3370d1a.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:53 -05:00
Tom Zanussi ad42febe51 tracing: Add hist trigger timestamp support
Add support for a timestamp event field.  This is actually a 'pseudo-'
event field in that it behaves like it's part of the event record, but
is really part of the corresponding ring buffer event.

To make use of the timestamp field, users can specify
"common_timestamp" as a field name for any histogram.  Note that this
doesn't make much sense on its own either as either a key or value,
but needs to be supported even so, since follow-on patches will add
support for making use of this field in time deltas.  The
common_timestamp 'field' is not a bona fide event field - so you won't
find it in the event description - but rather it's a synthetic field
that can be used like a real field.

Note that the use of this field requires the ring buffer be put into
'absolute timestamp' mode, which saves the complete timestamp for each
event rather than an offset.  This mode will be enabled if and only if
a histogram makes use of the "common_timestamp" field.

Link: http://lkml.kernel.org/r/97afbd646ed146e26271f3458b4b33e16d7817c2.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Baohong Liu <baohong.liu@intel.com>
[kasan use-after-free fix]
Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:52 -05:00
Tom Zanussi 9b1ae035c9 tracing: Break out hist trigger assignment parsing
This will make it easier to add variables, and makes the parsing code
cleaner regardless.

Link: http://lkml.kernel.org/r/e574b3291bbe15e35a4dfc87e5395aa715701c98.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Rajvi Jingar <rajvi.jingar@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:52 -05:00
Tom Zanussi fbd302cbeb tracing: Add ring buffer event param to hist field functions
Some events such as timestamps require access to a ring_buffer_event
struct; add a param so that hist field functions can access that.

Link: http://lkml.kernel.org/r/2ff4af18e72b6002eb86b26b2a7f39cef7d1dfe4.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:52 -05:00
Tom Zanussi 1ac4f51c0e tracing: Give event triggers access to ring_buffer_event
The ring_buffer event can provide a timestamp that may be useful to
various triggers - pass it into the handlers for that purpose.

Link: http://lkml.kernel.org/r/6de592683b59fa70ffa5d43d0109896623fc1367.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:51 -05:00
Tom Zanussi 2c1ea60b19 tracing: Add timestamp_mode trace file
Add a new option flag indicating whether or not the ring buffer is in
'absolute timestamp' mode.

Currently this is only set/unset by hist triggers that make use of a
common_timestamp.  As such, there's no reason to make this writeable
for users - its purpose is only to allow users to determine
unequivocally whether or not the ring buffer is in that mode (although
absolute timestamps can coexist with the normal delta timestamps, when
the ring buffer is in absolute mode, timestamps written while absolute
mode is in effect take up more space in the buffer, and are not as
efficient).

Link: http://lkml.kernel.org/r/e8aa7b1cde1cf15014e66545d06ac6ef2ebba456.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:51 -05:00
Tom Zanussi dc4e2801d4 ring-buffer: Redefine the unimplemented RINGBUF_TYPE_TIME_STAMP
RINGBUF_TYPE_TIME_STAMP is defined but not used, and from what I can
gather was reserved for something like an absolute timestamp feature
for the ring buffer, if not a complete replacement of the current
time_delta scheme.

This code redefines RINGBUF_TYPE_TIME_STAMP to implement absolute time
stamps.  Another way to look at it is that it essentially forces
extended time_deltas for all events.

The motivation for doing this is to enable time_deltas that aren't
dependent on previous events in the ring buffer, making it feasible to
use the ring_buffer_event timetamps in a more random-access way, for
purposes other than serial event printing.

To set/reset this mode, use tracing_set_timestamp_abs() from the
previous interface patch.

Link: http://lkml.kernel.org/r/477b362dba1ce7fab9889a1a8e885a62c472f041.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:50 -05:00
Tom Zanussi 00b4145298 ring-buffer: Add interface for setting absolute time stamps
Define a new function, tracing_set_time_stamp_abs(), which can be used
to enable or disable the use of absolute timestamps rather than time
deltas for a trace array.

Only the interface is added here; a subsequent patch will add the
underlying implementation.

Link: http://lkml.kernel.org/r/ce96119de44c7fe0ee44786d15254e9b493040d3.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Baohong Liu <baohong.liu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:50 -05:00
Vedang Patel c193707dde tracing: Remove code which merges duplicates
We now have the logic to detect and remove duplicates in the
tracing_map hash table. The code which merges duplicates in the
histogram is redundant now. So, modify this code just to detect
duplicates. The duplication detection code is still kept to ensure
that any rare race condition which might cause duplicates does not go
unnoticed.

Link: http://lkml.kernel.org/r/55215cf59e2674391bdaf772fdafc4c393352b03.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:49 -05:00
Vedang Patel cbf4100efb tracing: Add support to detect and avoid duplicates
A duplicate in the tracing_map hash table is when 2 different entries
have the same key and, as a result, the key_hash. This is possible due
to a race condition in the algorithm. This race condition is inherent to
the algorithm and not a bug. This was fine because, until now, we were
only interested in the sum of all the values related to a particular
key (the duplicates are dealt with in tracing_map_sort_entries()). But,
with the inclusion of variables[1], we are interested in individual
values. So, it will not be clear what value to choose when
there are duplicates. So, the duplicates need to be removed.

The duplicates can occur in the code in the following scenarios:

- A thread is in the process of adding a new element. It has
successfully executed cmpxchg() and inserted the key. But, it is still
not done acquiring the trace_map_elt struct, populating it and storing
the pointer to the struct in the value field of tracing_map hash table.
If another thread comes in at this time and wants to add an element with
the same key, it will not see the current element and add a new one.

- There are multiple threads trying to execute cmpxchg at the same time,
one of the threads will succeed and the others will fail. The ones which
fail will go ahead increment 'idx' and add a new element there creating
a duplicate.

This patch detects and avoids the first condition by asking the thread
which detects the duplicate to loop one more time. There is also a
possibility of infinite loop if the thread which is trying to insert
goes to sleep indefinitely and the one which is trying to insert a new
element detects a duplicate. Which is why, the thread loops for
map_size iterations before returning NULL.

The second scenario is avoided by preventing the threads which failed
cmpxchg() from incrementing idx. This way, they will loop
around and check if the thread which succeeded in executing cmpxchg()
had the same key.

[1] http://lkml.kernel.org/r/cover.1498510759.git.tom.zanussi@linux.intel.com

Link: http://lkml.kernel.org/r/e178e89ec399240331d383bd5913d649713110f4.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:49 -05:00
Teng Qin 95da0cdb72 bpf: add support to read sample address in bpf program
This commit adds new field "addr" to bpf_perf_event_data which could be
read and used by bpf programs attached to perf events. The value of the
field is copied from bpf_perf_event_data_kern.addr and contains the
address value recorded by specifying sample_type with PERF_SAMPLE_ADDR
when calling perf_event_open.

Signed-off-by: Teng Qin <qinteng@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-08 02:22:34 +01:00
Ingo Molnar 8af31363cd Linux 4.16-rc4
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Merge tag 'v4.16-rc4' into perf/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-06 07:30:22 +01:00
Ingo Molnar 7057bb975d Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-17 11:39:28 +01:00
Daniel Borkmann 9c481b908b bpf: fix bpf_prog_array_copy_to_user warning from perf event prog query
syzkaller tried to perform a prog query in perf_event_query_prog_array()
where struct perf_event_query_bpf had an ids_len of 1,073,741,353 and
thus causing a warning due to failed kcalloc() allocation out of the
bpf_prog_array_copy_to_user() helper. Given we cannot attach more than
64 programs to a perf event, there's no point in allowing huge ids_len.
Therefore, allow a buffer that would fix the maximum number of ids and
also add a __GFP_NOWARN to the temporary ids buffer.

Fixes: f371b304f1 ("bpf/tracing: allow user space to query prog array on the same tp")
Fixes: 0911287ce3 ("bpf: fix bpf_prog_array_copy_to_user() issues")
Reported-by: syzbot+cab5816b0edbabf598b3@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-02-14 08:59:37 -08:00
Linus Torvalds a9a08845e9 vfs: do bulk POLL* -> EPOLL* replacement
This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:

    for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
        L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
        for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
    done

with de-mangling cleanups yet to come.

NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do.  But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.

The next patch from Al will sort out the final differences, and we
should be all done.

Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-11 14:34:03 -08:00
Linus Torvalds 8158c2ffa4 Al Viro discovered some breakage with the parsing of the set_ftrace_filter
as well as the removing of function probes.
 
 This fixes the code with Al's suggestions. I also added a few selftests
 to test the broken cases such that they wont happen again.
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Merge tag 'trace-v4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Al Viro discovered some breakage with the parsing of the
  set_ftrace_filter as well as the removing of function probes.

  This fixes the code with Al's suggestions. I also added a few
  selftests to test the broken cases such that they wont happen
  again"

* tag 'trace-v4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  selftests/ftrace: Add more tests for removing of function probes
  selftests/ftrace: Add some missing glob checks
  selftests/ftrace: Have reset_ftrace_filter handle multiple instances
  selftests/ftrace: Have reset_ftrace_filter handle modules
  tracing: Fix parsing of globs with a wildcard at the beginning
  ftrace: Remove incorrect setting of glob search field
2018-02-09 14:47:09 -08:00
Steven Rostedt (VMware) 0723402141 tracing: Fix parsing of globs with a wildcard at the beginning
Al Viro reported:

    For substring - sure, but what about something like "*a*b" and "a*b"?
    AFAICS, filter_parse_regex() ends up with identical results in both
    cases - MATCH_GLOB and *search = "a*b".  And no way for the caller
    to tell one from another.

Testing this with the following:

 # cd /sys/kernel/tracing
 # echo '*raw*lock' > set_ftrace_filter
 bash: echo: write error: Invalid argument

With this patch:

 # echo '*raw*lock' > set_ftrace_filter
 # cat set_ftrace_filter
_raw_read_trylock
_raw_write_trylock
_raw_read_unlock
_raw_spin_unlock
_raw_write_unlock
_raw_spin_trylock
_raw_spin_lock
_raw_write_lock
_raw_read_lock

Al recommended not setting the search buffer to skip the first '*' unless we
know we are not using MATCH_GLOB. This implements his suggested logic.

Link: http://lkml.kernel.org/r/20180127170748.GF13338@ZenIV.linux.org.uk

Cc: stable@vger.kernel.org
Fixes: 60f1d5e3ba ("ftrace: Support full glob matching")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Suggsted-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-02-08 10:11:47 -05:00
Steven Rostedt (VMware) 7b65865627 ftrace: Remove incorrect setting of glob search field
__unregister_ftrace_function_probe() will incorrectly parse the glob filter
because it resets the search variable that was setup by filter_parse_regex().

Al Viro reported this:

    After that call of filter_parse_regex() we could have func_g.search not
    equal to glob only if glob started with '!' or '*'.  In the former case
    we would've buggered off with -EINVAL (not = 1).  In the latter we
    would've set func_g.search equal to glob + 1, calculated the length of
    that thing in func_g.len and proceeded to reset func_g.search back to
    glob.

    Suppose the glob is e.g. *foo*.  We end up with
	    func_g.type = MATCH_MIDDLE_ONLY;
	    func_g.len = 3;
	    func_g.search = "*foo";
    Feeding that to ftrace_match_record() will not do anything sane - we
    will be looking for names containing "*foo" (->len is ignored for that
    one).

Link: http://lkml.kernel.org/r/20180127031706.GE13338@ZenIV.linux.org.uk

Cc: stable@vger.kernel.org
Fixes: 3ba0092971 ("ftrace: Introduce ftrace_glob structure")
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-02-08 10:11:11 -05:00
Song Liu 33ea4b2427 perf/core: Implement the 'perf_uprobe' PMU
This patch adds perf_uprobe support with similar pattern as previous
patch (for kprobe).

Two functions, create_local_trace_uprobe() and
destroy_local_trace_uprobe(), are created so a uprobe can be created
and attached to the file descriptor created by perf_event_open().

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Yonghong Song <yhs@fb.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Cc: <daniel@iogearbox.net>
Cc: <davem@davemloft.net>
Cc: <kernel-team@fb.com>
Cc: <rostedt@goodmis.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20171206224518.3598254-7-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-06 11:29:28 +01:00
Song Liu e12f03d703 perf/core: Implement the 'perf_kprobe' PMU
A new PMU type, perf_kprobe is added. Based on attr from perf_event_open(),
perf_kprobe creates a kprobe (or kretprobe) for the perf_event. This
kprobe is private to this perf_event, and thus not added to global
lists, and not available in tracefs.

Two functions, create_local_trace_kprobe() and
destroy_local_trace_kprobe()  are added to created and destroy these
local trace_kprobe.

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Yonghong Song <yhs@fb.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Cc: <daniel@iogearbox.net>
Cc: <davem@davemloft.net>
Cc: <kernel-team@fb.com>
Cc: <rostedt@goodmis.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20171206224518.3598254-6-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-06 11:29:26 +01:00
Linus Torvalds 27529c891b Mostly clean ups and small fixes
There's not much changes for the tracing system this release.
 Mostly small clean ups and fixes.
 
 The biggest change is to how bprintf works. bprintf is used by
 trace_printk() to just save the format and args of a printf call,
 and the formatting is done when the trace buffer is read. This is
 done to keep the formatting out of the fast path (this was recommended
 by you). The issue is when arguments are de-referenced.
 
 If a pointer is saved, and the format has something like "%*pbl",
 when the buffer is read, it will de-reference the argument then.
 The problem is if the data no longer exists. This can cause the
 kernel to oops.
 
 The fix for this was to make these de-reference pointes do
 the formatting at the time it is called (the fast path), as
 this guarantees that the data exists (and doesn't change later)
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Merge tag 'trace-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "There's not much changes for the tracing system this release. Mostly
  small clean ups and fixes.

  The biggest change is to how bprintf works. bprintf is used by
  trace_printk() to just save the format and args of a printf call, and
  the formatting is done when the trace buffer is read. This is done to
  keep the formatting out of the fast path (this was recommended by
  you). The issue is when arguments are de-referenced.

  If a pointer is saved, and the format has something like "%*pbl", when
  the buffer is read, it will de-reference the argument then. The
  problem is if the data no longer exists. This can cause the kernel to
  oops.

  The fix for this was to make these de-reference pointes do the
  formatting at the time it is called (the fast path), as this
  guarantees that the data exists (and doesn't change later)"

* tag 'trace-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  vsprintf: Do not have bprintf dereference pointers
  ftrace: Mark function tracer test functions noinline/noclone
  trace_uprobe: Display correct offset in uprobe_events
  tracing: Make sure the parsed string always terminates with '\0'
  tracing: Clear parser->idx if only spaces are read
  tracing: Detect the string nul character when parsing user input string
2018-02-01 13:15:23 -08:00
Linus Torvalds b2fe5fa686 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) Significantly shrink the core networking routing structures. Result
    of http://vger.kernel.org/~davem/seoul2017_netdev_keynote.pdf

 2) Add netdevsim driver for testing various offloads, from Jakub
    Kicinski.

 3) Support cross-chip FDB operations in DSA, from Vivien Didelot.

 4) Add a 2nd listener hash table for TCP, similar to what was done for
    UDP. From Martin KaFai Lau.

 5) Add eBPF based queue selection to tun, from Jason Wang.

 6) Lockless qdisc support, from John Fastabend.

 7) SCTP stream interleave support, from Xin Long.

 8) Smoother TCP receive autotuning, from Eric Dumazet.

 9) Lots of erspan tunneling enhancements, from William Tu.

10) Add true function call support to BPF, from Alexei Starovoitov.

11) Add explicit support for GRO HW offloading, from Michael Chan.

12) Support extack generation in more netlink subsystems. From Alexander
    Aring, Quentin Monnet, and Jakub Kicinski.

13) Add 1000BaseX, flow control, and EEE support to mvneta driver. From
    Russell King.

14) Add flow table abstraction to netfilter, from Pablo Neira Ayuso.

15) Many improvements and simplifications to the NFP driver bpf JIT,
    from Jakub Kicinski.

16) Support for ipv6 non-equal cost multipath routing, from Ido
    Schimmel.

17) Add resource abstration to devlink, from Arkadi Sharshevsky.

18) Packet scheduler classifier shared filter block support, from Jiri
    Pirko.

19) Avoid locking in act_csum, from Davide Caratti.

20) devinet_ioctl() simplifications from Al viro.

21) More TCP bpf improvements from Lawrence Brakmo.

22) Add support for onlink ipv6 route flag, similar to ipv4, from David
    Ahern.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1925 commits)
  tls: Add support for encryption using async offload accelerator
  ip6mr: fix stale iterator
  net/sched: kconfig: Remove blank help texts
  openvswitch: meter: Use 64-bit arithmetic instead of 32-bit
  tcp_nv: fix potential integer overflow in tcpnv_acked
  r8169: fix RTL8168EP take too long to complete driver initialization.
  qmi_wwan: Add support for Quectel EP06
  rtnetlink: enable IFLA_IF_NETNSID for RTM_NEWLINK
  ipmr: Fix ptrdiff_t print formatting
  ibmvnic: Wait for device response when changing MAC
  qlcnic: fix deadlock bug
  tcp: release sk_frag.page in tcp_disconnect
  ipv4: Get the address of interface correctly.
  net_sched: gen_estimator: fix lockdep splat
  net: macb: Handle HRESP error
  net/mlx5e: IPoIB, Fix copy-paste bug in flow steering refactoring
  ipv6: addrconf: break critical section in addrconf_verify_rtnl()
  ipv6: change route cache aging logic
  i40e/i40evf: Update DESC_NEEDED value to reflect larger value
  bnxt_en: cleanup DIM work on device shutdown
  ...
2018-01-31 14:31:10 -08:00
Linus Torvalds 168fe32a07 Merge branch 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull poll annotations from Al Viro:
 "This introduces a __bitwise type for POLL### bitmap, and propagates
  the annotations through the tree. Most of that stuff is as simple as
  'make ->poll() instances return __poll_t and do the same to local
  variables used to hold the future return value'.

  Some of the obvious brainos found in process are fixed (e.g. POLLIN
  misspelled as POLL_IN). At that point the amount of sparse warnings is
  low and most of them are for genuine bugs - e.g. ->poll() instance
  deciding to return -EINVAL instead of a bitmap. I hadn't touched those
  in this series - it's large enough as it is.

  Another problem it has caught was eventpoll() ABI mess; select.c and
  eventpoll.c assumed that corresponding POLL### and EPOLL### were
  equal. That's true for some, but not all of them - EPOLL### are
  arch-independent, but POLL### are not.

  The last commit in this series separates userland POLL### values from
  the (now arch-independent) kernel-side ones, converting between them
  in the few places where they are copied to/from userland. AFAICS, this
  is the least disruptive fix preserving poll(2) ABI and making epoll()
  work on all architectures.

  As it is, it's simply broken on sparc - try to give it EPOLLWRNORM and
  it will trigger only on what would've triggered EPOLLWRBAND on other
  architectures. EPOLLWRBAND and EPOLLRDHUP, OTOH, are never triggered
  at all on sparc. With this patch they should work consistently on all
  architectures"

* 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (37 commits)
  make kernel-side POLL... arch-independent
  eventpoll: no need to mask the result of epi_item_poll() again
  eventpoll: constify struct epoll_event pointers
  debugging printk in sg_poll() uses %x to print POLL... bitmap
  annotate poll(2) guts
  9p: untangle ->poll() mess
  ->si_band gets POLL... bitmap stored into a user-visible long field
  ring_buffer_poll_wait() return value used as return value of ->poll()
  the rest of drivers/*: annotate ->poll() instances
  media: annotate ->poll() instances
  fs: annotate ->poll() instances
  ipc, kernel, mm: annotate ->poll() instances
  net: annotate ->poll() instances
  apparmor: annotate ->poll() instances
  tomoyo: annotate ->poll() instances
  sound: annotate ->poll() instances
  acpi: annotate ->poll() instances
  crypto: annotate ->poll() instances
  block: annotate ->poll() instances
  x86: annotate ->poll() instances
  ...
2018-01-30 17:58:07 -08:00
Linus Torvalds d772794637 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The main RCU changes in this cycle were:

   - Updates to use cond_resched() instead of cond_resched_rcu_qs()
     where feasible (currently everywhere except in kernel/rcu and in
     kernel/torture.c). Also a couple of fixes to avoid sending IPIs to
     offline CPUs.

   - Updates to simplify RCU's dyntick-idle handling.

   - Updates to remove almost all uses of smp_read_barrier_depends() and
     read_barrier_depends().

   - Torture-test updates.

   - Miscellaneous fixes"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits)
  torture: Save a line in stutter_wait(): while -> for
  torture: Eliminate torture_runnable and perf_runnable
  torture: Make stutter less vulnerable to compilers and races
  locking/locktorture: Fix num reader/writer corner cases
  locking/locktorture: Fix rwsem reader_delay
  torture: Place all torture-test modules in one MAINTAINERS group
  rcutorture/kvm-build.sh: Skip build directory check
  rcutorture: Simplify functions.sh include path
  rcutorture: Simplify logging
  rcutorture/kvm-recheck-*: Improve result directory readability check
  rcutorture/kvm.sh: Support execution from any directory
  rcutorture/kvm.sh: Use consistent help text for --qemu-args
  rcutorture/kvm.sh: Remove unused variable, `alldone`
  rcutorture: Remove unused script, config2frag.sh
  rcutorture/configinit: Fix build directory error message
  rcutorture: Preempt RCU-preempt readers more vigorously
  torture: Reduce #ifdefs for preempt_schedule()
  rcu: Remove have_rcu_nocb_mask from tree_plugin.h
  rcu: Add comment giving debug strategy for double call_rcu()
  tracing, rcu: Hide trace event rcu_nocb_wake when not used
  ...
2018-01-30 10:15:30 -08:00
David S. Miller 955bd1d216 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-24 23:44:15 -05:00
Andi Kleen dd3dad0d71 ftrace: Mark function tracer test functions noinline/noclone
The ftrace function tracer self tests calls some functions to verify
the get traced. This relies on them not being inlined. Previously
this was ensured by putting them into another file, but with LTO
the compiler can inline across files, which makes the tests fail.

Mark these functions as noinline and noclone.

Link: http://lkml.kernel.org/r/20171221233732.31896-1-andi@firstfloor.org

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23 15:57:29 -05:00
Ravi Bangoria 0e4d819d08 trace_uprobe: Display correct offset in uprobe_events
Recently, how the pointers being printed with %p has been changed
by commit ad67b74d24 ("printk: hash addresses printed with %p").
This is causing a regression while showing offset in the
uprobe_events file. Instead of %p, use %px to display offset.

Before patch:

  # perf probe -vv -x /tmp/a.out main
  Opening /sys/kernel/debug/tracing//uprobe_events write=1
  Writing event: p:probe_a/main /tmp/a.out:0x58c

  # cat /sys/kernel/debug/tracing/uprobe_events
  p:probe_a/main /tmp/a.out:0x0000000049a0f352

After patch:

  # cat /sys/kernel/debug/tracing/uprobe_events
  p:probe_a/main /tmp/a.out:0x000000000000058c

Link: http://lkml.kernel.org/r/20180106054246.15375-1-ravi.bangoria@linux.vnet.ibm.com

Cc: stable@vger.kernel.org
Fixes: ad67b74d24 ("printk: hash addresses printed with %p")
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23 15:57:29 -05:00
Changbin Du f4d0706cde tracing: Make sure the parsed string always terminates with '\0'
Always mark the parsed string with a terminated nul '\0' character. This removes
the need for the users to have to append the '\0' before using the parsed string.

Link: http://lkml.kernel.org/r/1516093350-12045-4-git-send-email-changbin.du@intel.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23 15:57:28 -05:00
Changbin Du 76638d9650 tracing: Clear parser->idx if only spaces are read
If only spaces were read while parsing the next string, then parser->idx should be
cleared in order to make trace_parser_loaded() return false.

Link: http://lkml.kernel.org/r/1516093350-12045-3-git-send-email-changbin.du@intel.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23 15:57:28 -05:00
Changbin Du 921a7acd85 tracing: Detect the string nul character when parsing user input string
User space can pass in a C nul character '\0' along with its input. The
function trace_get_user() will try to process it as a normal character,
and that will fail to parse.

open("/sys/kernel/debug/tracing//set_ftrace_pid", O_WRONLY|O_TRUNC) = 3
write(3, " \0", 2)                      = -1 EINVAL (Invalid argument)

while parse can handle spaces, so below works.

$ echo "" > set_ftrace_pid
$ echo " " > set_ftrace_pid
$ echo -n " " > set_ftrace_pid

Have the parser stop on '\0' and cease any further parsing. Only process
the characters up to the nul '\0' character and do not process it.

Link: http://lkml.kernel.org/r/1516093350-12045-2-git-send-email-changbin.du@intel.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23 15:57:27 -05:00
Steven Rostedt (VMware) 2ee5b92a25 tracing: Update stack trace skipping for ORC unwinder
With the addition of ORC unwinder and FRAME POINTER unwinder, the stack
trace skipping requirements have changed.

I went through the tracing stack trace dumps with ORC and with frame
pointers and recalculated the proper values.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23 15:57:00 -05:00
Steven Rostedt (VMware) 6be7fa3c74 ftrace, orc, x86: Handle ftrace dynamically allocated trampolines
The function tracer can create a dynamically allocated trampoline that is
called by the function mcount or fentry hook that is used to call the
function callback that is registered. The problem is that the orc undwinder
will bail if it encounters one of these trampolines. This breaks the stack
trace of function callbacks, which include the stack tracer and setting the
stack trace for individual functions.

Since these dynamic trampolines are basically copies of the static ftrace
trampolines defined in ftrace_*.S, we do not need to create new orc entries
for the dynamic trampolines. Finding the return address on the stack will be
identical as the functions that were copied to create the dynamic
trampolines. When encountering a ftrace dynamic trampoline, we can just use
the orc entry of the ftrace static function that was copied for that
trampoline.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23 15:56:55 -05:00
David S. Miller ea9722e265 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2018-01-19

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) bpf array map HW offload, from Jakub.

2) support for bpf_get_next_key() for LPM map, from Yonghong.

3) test_verifier now runs loaded programs, from Alexei.

4) xdp cpumap monitoring, from Jesper.

5) variety of tests, cleanups and small x64 JIT optimization, from Daniel.

6) user space can now retrieve HW JITed program, from Jiong.

Note there is a minor conflict between Russell's arm32 JIT fixes
and removal of bpf_jit_enable variable by Daniel which should
be resolved by keeping Russell's comment and removing that variable.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-20 22:03:46 -05:00
David S. Miller 8565d26bcb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The BPF verifier conflict was some minor contextual issue.

The TUN conflict was less trivial.  Cong Wang fixed a memory leak of
tfile->tx_array in 'net'.  This is an skb_array.  But meanwhile in
net-next tun changed tfile->tx_arry into tfile->tx_ring which is a
ptr_ring.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-19 22:59:33 -05:00
Steven Rostedt (VMware) 1ebe1eaf2f tracing: Fix converting enum's from the map in trace_event_eval_update()
Since enums do not get converted by the TRACE_EVENT macro into their values,
the event format displaces the enum name and not the value. This breaks
tools like perf and trace-cmd that need to interpret the raw binary data. To
solve this, an enum map was created to convert these enums into their actual
numbers on boot up. This is done by TRACE_EVENTS() adding a
TRACE_DEFINE_ENUM() macro.

Some enums were not being converted. This was caused by an optization that
had a bug in it.

All calls get checked against this enum map to see if it should be converted
or not, and it compares the call's system to the system that the enum map
was created under. If they match, then they call is processed.

To cut down on the number of iterations needed to find the maps with a
matching system, since calls and maps are grouped by system, when a match is
made, the index into the map array is saved, so that the next call, if it
belongs to the same system as the previous call, could start right at that
array index and not have to scan all the previous arrays.

The problem was, the saved index was used as the variable to know if this is
a call in a new system or not. If the index was zero, it was assumed that
the call is in a new system and would keep incrementing the saved index
until it found a matching system. The issue arises when the first matching
system was at index zero. The next map, if it belonged to the same system,
would then think it was the first match and increment the index to one. If
the next call belong to the same system, it would begin its search of the
maps off by one, and miss the first enum that should be converted. This left
a single enum not converted properly.

Also add a comment to describe exactly what that index was for. It took me a
bit too long to figure out what I was thinking when debugging this issue.

Link: http://lkml.kernel.org/r/717BE572-2070-4C1E-9902-9F2E0FEDA4F8@oracle.com

Cc: stable@vger.kernel.org
Fixes: 0c564a538a ("tracing: Add TRACE_DEFINE_ENUM() macro to map enums to their values")
Reported-by: Chuck Lever <chuck.lever@oracle.com>
Teste-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-18 15:53:10 -05:00
Steven Rostedt (VMware) 0164e0d7e8 ring-buffer: Fix duplicate results in mapping context to bits in recursive lock
In bringing back the context checks, the code checks first if its normal
(non-interrupt) context, and then for NMI then IRQ then softirq. The final
check is redundant. Since the if branch is only hit if the context is one of
NMI, IRQ, or SOFTIRQ, if it's not NMI or IRQ there's no reason to check if
it is SOFTIRQ. The current code returns the same result even if its not a
SOFTIRQ. Which is confusing.

  pc & SOFTIRQ_OFFSET ? 2 : RB_CTX_SOFTIRQ

Is redundant as RB_CTX_SOFTIRQ *is* 2!

Fixes: a0e3a18f4b ("ring-buffer: Bring back context level recursive checks")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-18 15:45:48 -05:00
Yonghong Song eefa864a81 bpf: change fake_ip for bpf_trace_printk helper
Currently, for bpf_trace_printk helper, fake ip address 0x1
is used with comments saying that fake ip will not be printed.
This is indeed true for 4.12 and earlier version, but for
4.13 and later version, the ip address will be printed if
it cannot be resolved with kallsym. Running samples/bpf/tracex5
program and you will have the following in the debugfs
trace_pipe output:
  ...
  <...>-1819  [003] ....   443.497877: 0x00000001: mmap
  <...>-1819  [003] ....   443.498289: 0x00000001: syscall=102 (one of get/set uid/pid/gid)
  ...

The kernel commit changed this behavior is:
  commit feaf1283d1
  Author: Steven Rostedt (VMware) <rostedt@goodmis.org>
  Date:   Thu Jun 22 17:04:55 2017 -0400

      tracing: Show address when function names are not found
  ...

This patch changed the comment and also altered the fake ip
address to 0x0 as users may think 0x1 has some special meaning
while it doesn't. The new output:
  ...
  <...>-1799  [002] ....    25.953576: 0: mmap
  <...>-1799  [002] ....    25.953865: 0: read(fd=0, buf=00000000053936b5, size=512)
  ...

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-01-18 01:51:42 +01:00
David S. Miller c02b3741eb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Overlapping changes all over.

The mini-qdisc bits were a little bit tricky, however.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-17 00:10:42 -05:00
Randy Dunlap 68e76e034b tracing: Prevent PROFILE_ALL_BRANCHES when FORTIFY_SOURCE=y
I regularly get 50 MB - 60 MB files during kernel randconfig builds.
These large files mostly contain (many repeats of; e.g., 124,594):

In file included from ../include/linux/string.h:6:0,
                 from ../include/linux/uuid.h:20,
                 from ../include/linux/mod_devicetable.h:13,
                 from ../scripts/mod/devicetable-offsets.c:3:
../include/linux/compiler.h:64:4: warning: '______f' is static but declared in inline function 'strcpy' which is not static [enabled by default]
    ______f = {     \
    ^
../include/linux/compiler.h:56:23: note: in expansion of macro '__trace_if'
                       ^
../include/linux/string.h:425:2: note: in expansion of macro 'if'
  if (p_size == (size_t)-1 && q_size == (size_t)-1)
  ^

This only happens when CONFIG_FORTIFY_SOURCE=y and
CONFIG_PROFILE_ALL_BRANCHES=y, so prevent PROFILE_ALL_BRANCHES if
FORTIFY_SOURCE=y.

Link: http://lkml.kernel.org/r/9199446b-a141-c0c3-9678-a3f9107f2750@infradead.org

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-15 14:15:31 -05:00
Steven Rostedt (VMware) a0e3a18f4b ring-buffer: Bring back context level recursive checks
Commit 1a149d7d3f ("ring-buffer: Rewrite trace_recursive_(un)lock() to be
simpler") replaced the context level recursion checks with a simple counter.
This would prevent the ring buffer code from recursively calling itself more
than the max number of contexts that exist (Normal, softirq, irq, nmi). But
this change caused a lockup in a specific case, which was during suspend and
resume using a global clock. Adding a stack dump to see where this occurred,
the issue was in the trace global clock itself:

  trace_buffer_lock_reserve+0x1c/0x50
  __trace_graph_entry+0x2d/0x90
  trace_graph_entry+0xe8/0x200
  prepare_ftrace_return+0x69/0xc0
  ftrace_graph_caller+0x78/0xa8
  queued_spin_lock_slowpath+0x5/0x1d0
  trace_clock_global+0xb0/0xc0
  ring_buffer_lock_reserve+0xf9/0x390

The function graph tracer traced queued_spin_lock_slowpath that was called
by trace_clock_global. This pointed out that the trace_clock_global() is not
reentrant, as it takes a spin lock. It depended on the ring buffer recursive
lock from letting that happen.

By removing the context detection and adding just a max number of allowable
recursions, it allowed the trace_clock_global() to be entered again and try
to retake the spinlock it already held, causing a deadlock.

Fixes: 1a149d7d3f ("ring-buffer: Rewrite trace_recursive_(un)lock() to be simpler")
Reported-by: David Weinehall <david.weinehall@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-15 12:28:06 -05:00
Masami Hiramatsu 540adea380 error-injection: Separate error-injection from kprobe
Since error-injection framework is not limited to be used
by kprobes, nor bpf. Other kernel subsystems can use it
freely for checking safeness of error-injection, e.g.
livepatch, ftrace etc.
So this separate error-injection framework from kprobes.

Some differences has been made:

- "kprobe" word is removed from any APIs/structures.
- BPF_ALLOW_ERROR_INJECTION() is renamed to
  ALLOW_ERROR_INJECTION() since it is not limited for BPF too.
- CONFIG_FUNCTION_ERROR_INJECTION is the config item of this
  feature. It is automatically enabled if the arch supports
  error injection feature for kprobe or ftrace etc.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-12 17:33:38 -08:00
Masami Hiramatsu 66665ad2f1 tracing/kprobe: bpf: Compare instruction pointer with original one
Compare instruction pointer with original one on the
stack instead using per-cpu bpf_kprobe_override flag.

This patch also consolidates reset_current_kprobe() and
preempt_enable_no_resched() blocks. Those can be done
in one place.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-12 17:33:38 -08:00
Masami Hiramatsu b4da3340ea tracing/kprobe: bpf: Check error injectable event is on function entry
Check whether error injectable event is on function entry or not.
Currently it checks the event is ftrace-based kprobes or not,
but that is wrong. It should check if the event is on the entry
of target function. Since error injection will override a function
to just return with modified return value, that operation must
be done before the target function starts making stackframe.

As a side effect, bpf error injection is no need to depend on
function-tracer. It can work with sw-breakpoint based kprobe
events too.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-12 17:33:37 -08:00
Ingo Molnar 475c5ee193 Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU updates from Paul E. McKenney:

- Updates to use cond_resched() instead of cond_resched_rcu_qs()
  where feasible (currently everywhere except in kernel/rcu and
  in kernel/torture.c).  Also a couple of fixes to avoid sending
  IPIs to offline CPUs.

- Updates to simplify RCU's dyntick-idle handling.

- Updates to remove almost all uses of smp_read_barrier_depends()
  and read_barrier_depends().

- Miscellaneous fixes.

- Torture-test updates.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-03 14:14:18 +01:00
David S. Miller 6bb8824732 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
net/ipv6/ip6_gre.c is a case of parallel adds.

include/trace/events/tcp.h is a little bit more tricky.  The removal
of in-trace-macro ifdefs in 'net' paralleled with moving
show_tcp_state_name and friends over to include/trace/events/sock.h
in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-29 15:42:26 -05:00
Steven Rostedt (VMware) 4397f04575 tracing: Fix possible double free on failure of allocating trace buffer
Jing Xia and Chunyan Zhang reported that on failing to allocate part of the
tracing buffer, memory is freed, but the pointers that point to them are not
initialized back to NULL, and later paths may try to free the freed memory
again. Jing and Chunyan fixed one of the locations that does this, but
missed a spot.

Link: http://lkml.kernel.org/r/20171226071253.8968-1-chunyan.zhang@spreadtrum.com

Cc: stable@vger.kernel.org
Fixes: 737223fbca ("tracing: Consolidate buffer allocation code")
Reported-by: Jing Xia <jing.xia@spreadtrum.com>
Reported-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:21:27 -05:00
Jing Xia 24f2aaf952 tracing: Fix crash when it fails to alloc ring buffer
Double free of the ring buffer happens when it fails to alloc new
ring buffer instance for max_buffer if TRACER_MAX_TRACE is configured.
The root cause is that the pointer is not set to NULL after the buffer
is freed in allocate_trace_buffers(), and the freeing of the ring
buffer is invoked again later if the pointer is not equal to Null,
as:

instance_mkdir()
    |-allocate_trace_buffers()
        |-allocate_trace_buffer(tr, &tr->trace_buffer...)
	|-allocate_trace_buffer(tr, &tr->max_buffer...)

          // allocate fail(-ENOMEM),first free
          // and the buffer pointer is not set to null
        |-ring_buffer_free(tr->trace_buffer.buffer)

       // out_free_tr
    |-free_trace_buffers()
        |-free_trace_buffer(&tr->trace_buffer);

	      //if trace_buffer is not null, free again
	    |-ring_buffer_free(buf->buffer)
                |-rb_free_cpu_buffer(buffer->buffers[cpu])
                    // ring_buffer_per_cpu is null, and
                    // crash in ring_buffer_per_cpu->pages

Link: http://lkml.kernel.org/r/20171226071253.8968-1-chunyan.zhang@spreadtrum.com

Cc: stable@vger.kernel.org
Fixes: 737223fbca ("tracing: Consolidate buffer allocation code")
Signed-off-by: Jing Xia <jing.xia@spreadtrum.com>
Signed-off-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:21:16 -05:00
Steven Rostedt (VMware) ae415fa4c5 ring-buffer: Do no reuse reader page if still in use
To free the reader page that is allocated with ring_buffer_alloc_read_page(),
ring_buffer_free_read_page() must be called. For faster performance, this
page can be reused by the ring buffer to avoid having to free and allocate
new pages.

The issue arises when the page is used with a splice pipe into the
networking code. The networking code may up the page counter for the page,
and keep it active while sending it is queued to go to the network. The
incrementing of the page ref does not prevent it from being reused in the
ring buffer, and this can cause the page that is being sent out to the
network to be modified before it is sent by reading new data.

Add a check to the page ref counter, and only reuse the page if it is not
being used anywhere else.

Cc: stable@vger.kernel.org
Fixes: 73a757e631 ("ring-buffer: Return reader page back into existing ring buffer")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:21:09 -05:00
Steven Rostedt (VMware) 6b7e633fe9 tracing: Remove extra zeroing out of the ring buffer page
The ring_buffer_read_page() takes care of zeroing out any extra data in the
page that it returns. There's no need to zero it out again from the
consumer. It was removed from one consumer of this function, but
read_buffers_splice_read() did not remove it, and worse, it contained a
nasty bug because of it.

Cc: stable@vger.kernel.org
Fixes: 2711ca237a ("ring-buffer: Move zeroing out excess in page to ring buffer code")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:20:59 -05:00
Steven Rostedt (VMware) 45d8b80c2a ring-buffer: Mask out the info bits when returning buffer page length
Two info bits were added to the "commit" part of the ring buffer data page
when returned to be consumed. This was to inform the user space readers that
events have been missed, and that the count may be stored at the end of the
page.

What wasn't handled, was the splice code that actually called a function to
return the length of the data in order to zero out the rest of the page
before sending it up to user space. These data bits were returned with the
length making the value negative, and that negative value was not checked.
It was compared to PAGE_SIZE, and only used if the size was less than
PAGE_SIZE. Luckily PAGE_SIZE is unsigned long which made the compare an
unsigned compare, meaning the negative size value did not end up causing a
large portion of memory to be randomly zeroed out.

Cc: stable@vger.kernel.org
Fixes: 66a8cb95ed ("ring-buffer: Add place holder recording of dropped events")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:18:10 -05:00
David S. Miller 59436c9ee1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2017-12-18

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Allow arbitrary function calls from one BPF function to another BPF function.
   As of today when writing BPF programs, __always_inline had to be used in
   the BPF C programs for all functions, unnecessarily causing LLVM to inflate
   code size. Handle this more naturally with support for BPF to BPF calls
   such that this __always_inline restriction can be overcome. As a result,
   it allows for better optimized code and finally enables to introduce core
   BPF libraries in the future that can be reused out of different projects.
   x86 and arm64 JIT support was added as well, from Alexei.

2) Add infrastructure for tagging functions as error injectable and allow for
   BPF to return arbitrary error values when BPF is attached via kprobes on
   those. This way of injecting errors generically eases testing and debugging
   without having to recompile or restart the kernel. Tags for opting-in for
   this facility are added with BPF_ALLOW_ERROR_INJECTION(), from Josef.

3) For BPF offload via nfp JIT, add support for bpf_xdp_adjust_head() helper
   call for XDP programs. First part of this work adds handling of BPF
   capabilities included in the firmware, and the later patches add support
   to the nfp verifier part and JIT as well as some small optimizations,
   from Jakub.

4) The bpftool now also gets support for basic cgroup BPF operations such
   as attaching, detaching and listing current BPF programs. As a requirement
   for the attach part, bpftool can now also load object files through
   'bpftool prog load'. This reuses libbpf which we have in the kernel tree
   as well. bpftool-cgroup man page is added along with it, from Roman.

5) Back then commit e87c6bc385 ("bpf: permit multiple bpf attachments for
   a single perf event") added support for attaching multiple BPF programs
   to a single perf event. Given they are configured through perf's ioctl()
   interface, the interface has been extended with a PERF_EVENT_IOC_QUERY_BPF
   command in this work in order to return an array of one or multiple BPF
   prog ids that are currently attached, from Yonghong.

6) Various minor fixes and cleanups to the bpftool's Makefile as well
   as a new 'uninstall' and 'doc-uninstall' target for removing bpftool
   itself or prior installed documentation related to it, from Quentin.

7) Add CONFIG_CGROUP_BPF=y to the BPF kernel selftest config file which is
   required for the test_dev_cgroup test case to run, from Naresh.

8) Fix reporting of XDP prog_flags for nfp driver, from Jakub.

9) Fix libbpf's exit code from the Makefile when libelf was not found in
   the system, also from Jakub.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-18 10:51:06 -05:00
Josef Bacik 46df3d209d trace: reenable preemption if we modify the ip
Things got moved around between the original bpf_override_return patches
and the final version, and now the ftrace kprobe dispatcher assumes if
you modified the ip that you also enabled preemption.  Make a comment of
this and enable preemption, this fixes the lockdep splat that happened
when using this feature.

Fixes: 9802d86585 ("bpf: add a bpf_override_function helper")
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-17 20:47:32 +01:00
Linus Torvalds 7a3c296ae0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Clamp timeouts to INT_MAX in conntrack, from Jay Elliot.

 2) Fix broken UAPI for BPF_PROG_TYPE_PERF_EVENT, from Hendrik
    Brueckner.

 3) Fix locking in ieee80211_sta_tear_down_BA_sessions, from Johannes
    Berg.

 4) Add missing barriers to ptr_ring, from Michael S. Tsirkin.

 5) Don't advertise gigabit in sh_eth when not available, from Thomas
    Petazzoni.

 6) Check network namespace when delivering to netlink taps, from Kevin
    Cernekee.

 7) Kill a race in raw_sendmsg(), from Mohamed Ghannam.

 8) Use correct address in TCP md5 lookups when replying to an incoming
    segment, from Christoph Paasch.

 9) Add schedule points to BPF map alloc/free, from Eric Dumazet.

10) Don't allow silly mtu values to be used in ipv4/ipv6 multicast, also
    from Eric Dumazet.

11) Fix SKB leak in tipc, from Jon Maloy.

12) Disable MAC learning on OVS ports of mlxsw, from Yuval Mintz.

13) SKB leak fix in skB_complete_tx_timestamp(), from Willem de Bruijn.

14) Add some new qmi_wwan device IDs, from Daniele Palmas.

15) Fix static key imbalance in ingress qdisc, from Jiri Pirko.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (76 commits)
  net: qcom/emac: Reduce timeout for mdio read/write
  net: sched: fix static key imbalance in case of ingress/clsact_init error
  net: sched: fix clsact init error path
  ip_gre: fix wrong return value of erspan_rcv
  net: usb: qmi_wwan: add Telit ME910 PID 0x1101 support
  pkt_sched: Remove TC_RED_OFFLOADED from uapi
  net: sched: Move to new offload indication in RED
  net: sched: Add TCA_HW_OFFLOAD
  net: aquantia: Increment driver version
  net: aquantia: Fix typo in ethtool statistics names
  net: aquantia: Update hw counters on hw init
  net: aquantia: Improve link state and statistics check interval callback
  net: aquantia: Fill in multicast counter in ndev stats from hardware
  net: aquantia: Fill ndev stat couters from hardware
  net: aquantia: Extend stat counters to 64bit values
  net: aquantia: Fix hardware DMA stream overload on large MRRS
  net: aquantia: Fix actual speed capabilities reporting
  sock: free skb in skb_complete_tx_timestamp on error
  s390/qeth: update takeover IPs after configuration change
  s390/qeth: lock IP table while applying takeover changes
  ...
2017-12-15 13:08:37 -08:00
Linus Torvalds 0424378781 Various fix ups.
- Comment fixes
  - Build fix
  - Better memory alloction (don't use NR_CPUS)
  - Configuration fix
  - Build warning fix
  - Enhanced callback parameter (to simplify users of trace hooks)
  - Give up on stack tracing when RCU isn't watching (it's a lost cause)
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Merge tag 'trace-v4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Various fix-ups:

   - comment fixes

   - build fix

   - better memory alloction (don't use NR_CPUS)

   - configuration fix

   - build warning fix

   - enhanced callback parameter (to simplify users of trace hooks)

   - give up on stack tracing when RCU isn't watching (it's a lost
     cause)"

* tag 'trace-v4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Have stack trace not record if RCU is not watching
  tracing: Pass export pointer as argument to ->write()
  ring-buffer: Remove unused function __rb_data_page_index()
  tracing: make PREEMPTIRQ_EVENTS depend on TRACING
  tracing: Allocate mask_str buffer dynamically
  tracing: always define trace_{irq,preempt}_{enable_disable}
  tracing: Fix code comments in trace.c
2017-12-14 18:21:33 -08:00
Steven Rostedt (VMware) b00d607bb1 tracing: Have stack trace not record if RCU is not watching
The stack tracer records a stack dump whenever it sees a stack usage that is
more than what it ever saw before. This can happen at any function that is
being traced. If it happens when the CPU is going idle (or other strange
locations), RCU may not be watching, and in this case, the recording of the
stack trace will trigger a warning. There's been lots of efforts to make
hacks to allow stack tracing to proceed even if RCU is not watching, but
this only causes more issues to appear. Simply do not trace a stack if RCU
is not watching. It probably isn't a bad stack anyway.

Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-14 20:48:22 -05:00
Yonghong Song f4e2298e63 bpf/tracing: fix kernel/events/core.c compilation error
Commit f371b304f1 ("bpf/tracing: allow user space to
query prog array on the same tp") introduced a perf
ioctl command to query prog array attached to the
same perf tracepoint. The commit introduced a
compilation error under certain config conditions, e.g.,
  (1). CONFIG_BPF_SYSCALL is not defined, or
  (2). CONFIG_TRACING is defined but neither CONFIG_UPROBE_EVENTS
       nor CONFIG_KPROBE_EVENTS is defined.

Error message:
  kernel/events/core.o: In function `perf_ioctl':
  core.c:(.text+0x98c4): undefined reference to `bpf_event_query_prog_array'

This patch fixed this error by guarding the real definition under
CONFIG_BPF_EVENTS and provided static inline dummy function
if CONFIG_BPF_EVENTS was not defined.
It renamed the function from bpf_event_query_prog_array to
perf_event_query_prog_array and moved the definition from linux/bpf.h
to linux/trace_events.h so the definition is in proximity to
other prog_array related functions.

Fixes: f371b304f1 ("bpf/tracing: allow user space to query prog array on the same tp")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-13 22:44:10 +01:00
Daniel Borkmann 283ca526a9 bpf: fix corruption on concurrent perf_event_output calls
When tracing and networking programs are both attached in the
system and both use event-output helpers that eventually call
into perf_event_output(), then we could end up in a situation
where the tracing attached program runs in user context while
a cls_bpf program is triggered on that same CPU out of softirq
context.

Since both rely on the same per-cpu perf_sample_data, we could
potentially corrupt it. This can only ever happen in a combination
of the two types; all tracing programs use a bpf_prog_active
counter to bail out in case a program is already running on
that CPU out of a different context. XDP and cls_bpf programs
by themselves don't have this issue as they run in the same
context only. Therefore, split both perf_sample_data so they
cannot be accessed from each other.

Fixes: 20b9d7ac48 ("bpf: avoid excessive stack usage for perf_sample_data")
Reported-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Song Liu <songliubraving@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 09:51:12 -08:00
Josef Bacik 9802d86585 bpf: add a bpf_override_function helper
Error injection is sloppy and very ad-hoc.  BPF could fill this niche
perfectly with it's kprobe functionality.  We could make sure errors are
only triggered in specific call chains that we care about with very
specific situations.  Accomplish this with the bpf_override_funciton
helper.  This will modify the probe'd callers return value to the
specified value and set the PC to an override function that simply
returns, bypassing the originally probed function.  This gives us a nice
clean way to implement systematic error injection for all of our code
paths.

Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 09:02:34 -08:00
Yonghong Song f371b304f1 bpf/tracing: allow user space to query prog array on the same tp
Commit e87c6bc385 ("bpf: permit multiple bpf attachments
for a single perf event") added support to attach multiple
bpf programs to a single perf event.
Although this provides flexibility, users may want to know
what other bpf programs attached to the same tp interface.
Besides getting visibility for the underlying bpf system,
such information may also help consolidate multiple bpf programs,
understand potential performance issues due to a large array,
and debug (e.g., one bpf program which overwrites return code
may impact subsequent program results).

Commit 2541517c32 ("tracing, perf: Implement BPF programs
attached to kprobes") utilized the existing perf ioctl
interface and added the command PERF_EVENT_IOC_SET_BPF
to attach a bpf program to a tracepoint. This patch adds a new
ioctl command, given a perf event fd, to query the bpf program
array attached to the same perf tracepoint event.

The new uapi ioctl command:
  PERF_EVENT_IOC_QUERY_BPF

The new uapi/linux/perf_event.h structure:
  struct perf_event_query_bpf {
       __u32	ids_len;
       __u32	prog_cnt;
       __u32	ids[0];
  };

User space provides buffer "ids" for kernel to copy to.
When returning from the kernel, the number of available
programs in the array is set in "prog_cnt".

The usage:
  struct perf_event_query_bpf *query =
    malloc(sizeof(*query) + sizeof(u32) * ids_len);
  query.ids_len = ids_len;
  err = ioctl(pmu_efd, PERF_EVENT_IOC_QUERY_BPF, query);
  if (err == 0) {
    /* query.prog_cnt is the number of available progs,
     * number of progs in ids: (ids_len == 0) ? 0 : query.prog_cnt
     */
  } else if (errno == ENOSPC) {
    /* query.ids_len number of progs copied,
     * query.prog_cnt is the number of available progs
     */
  } else {
      /* other errors */
  }

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 08:46:40 -08:00
Paul E. McKenney 1dfa55e019 Merge branches 'cond_resched.2017.12.04a', 'dyntick.2017.11.28a', 'fixes.2017.12.11a', 'srbd.2017.12.05a' and 'torture.2017.12.11a' into HEAD
cond_resched.2017.12.04a: Convert cond_resched_rcu_qs() to cond_resched()
dyntick.2017.11.28a: Make RCU dynticks handle interrupts from NMI
fixes.2017.12.11a: Miscellaneous fixes
srbd.2017.12.05a: Remove now-redundant smp_read_barrier_depends()
torture.2017.12.11a: Torture-testing update
2017-12-11 09:21:58 -08:00
Linus Torvalds 236fa078c6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Various TCP control block fixes, including one that crashes with
    SELinux, from David Ahern and Eric Dumazet.

 2) Fix ACK generation in rxrpc, from David Howells.

 3) ipvlan doesn't set the mark properly in the ipv4 route lookup key,
    from Gao Feng.

 4) SIT configuration doesn't take on the frag_off ipv4 field
    configuration properly, fix from Hangbin Liu.

 5) TSO can fail after device down/up on stmmac, fix from Lars Persson.

 6) Various bpftool fixes (mostly in JSON handling) from Quentin Monnet.

 7) Various SKB leak fixes in vhost/tun/tap (mostly observed as
    performance problems). From Wei Xu.

 8) mvpps's TX descriptors were not zero initialized, from Yan Markman.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (57 commits)
  tcp: use IPCB instead of TCP_SKB_CB in inet_exact_dif_match()
  tcp: add tcp_v4_fill_cb()/tcp_v4_restore_cb()
  rxrpc: Fix the MAINTAINERS record
  rxrpc: Use correct netns source in rxrpc_release_sock()
  liquidio: fix incorrect indentation of assignment statement
  stmmac: reset last TSO segment size after device open
  ipvlan: Add the skb->mark as flow4's member to lookup route
  s390/qeth: build max size GSO skbs on L2 devices
  s390/qeth: fix GSO throughput regression
  s390/qeth: fix thinko in IPv4 multicast address tracking
  tap: free skb if flags error
  tun: free skb in early errors
  vhost: fix skb leak in handle_rx()
  bnxt_en: Fix a variable scoping in bnxt_hwrm_do_send_msg()
  bnxt_en: fix dst/src fid for vxlan encap/decap actions
  bnxt_en: wildcard smac while creating tunnel decap filter
  bnxt_en: Need to unconditionally shut down RoCE in bnxt_shutdown
  phylink: ensure we take the link down when phylink_stop() is called
  sfp: warn about modules requiring address change sequence
  sfp: improve RX_LOS handling
  ...
2017-12-04 11:14:46 -08:00
Paul E. McKenney e31d28b6ab trace: Eliminate cond_resched_rcu_qs() in favor of cond_resched()
Now that cond_resched() also provides RCU quiescent states when
needed, it can be used in place of cond_resched_rcu_qs().  This
commit therefore makes this change.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
2017-12-04 10:28:58 -08:00
Felipe Balbi a773d41927 tracing: Pass export pointer as argument to ->write()
By passing an export descriptor to the write function, users don't need to
keep a global static pointer and can rely on container_of() to fetch their
own structure.

Link: http://lkml.kernel.org/r/20170602102025.5140-1-felipe.balbi@linux.intel.com

Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04 07:14:30 -05:00
Matthias Kaehlcke c4bfd39d7f ring-buffer: Remove unused function __rb_data_page_index()
This fixes the following warning when building with clang:

kernel/trace/ring_buffer.c:1842:1: error: unused function
    '__rb_data_page_index' [-Werror,-Wunused-function]

Link: http://lkml.kernel.org/r/20170518001415.5223-1-mka@chromium.org

Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04 07:04:01 -05:00
Arnd Bergmann 2dde6b0034 tracing: make PREEMPTIRQ_EVENTS depend on TRACING
When CONFIG_TRACING is disabled, the new preemptirq events tracer
produces a build failure:

In file included from kernel/trace/trace_irqsoff.c:17:0:
kernel/trace/trace.h: In function 'trace_test_and_set_recursion':
kernel/trace/trace.h:542:28: error: 'struct task_struct' has no member named 'trace_recursion'

Adding an explicit dependency avoids the broken configuration.

Link: http://lkml.kernel.org/r/20171103104031.270375-1-arnd@arndb.de

Fixes: d59158162e ("tracing: Add support for preempt and irq enable/disable events")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04 06:52:09 -05:00
Changbin Du 90e406f96f tracing: Allocate mask_str buffer dynamically
The default NR_CPUS can be very large, but actual possible nr_cpu_ids
usually is very small. For my x86 distribution, the NR_CPUS is 8192 and
nr_cpu_ids is 4. About 2 pages are wasted.

Most machines don't have so many CPUs, so define a array with NR_CPUS
just wastes memory. So let's allocate the buffer dynamically when need.

With this change, the mutext tracing_cpumask_update_lock also can be
removed now, which was used to protect mask_str.

Link: http://lkml.kernel.org/r/1512013183-19107-1-git-send-email-changbin.du@intel.com

Fixes: 36dfe9252b ("ftrace: make use of tracing_cpumask")
Cc: stable@vger.kernel.org
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04 06:52:08 -05:00
Chunyu Hu 5a93bae2c3 tracing: Fix code comments in trace.c
Naming in code comments for tracing_snapshot, tracing_snapshot_alloc
and trace_pid_filter_add_remove_task don't match the real function
names.  And latency_trace has been removed from tracing directory.
Fix them.

Link: http://lkml.kernel.org/r/1508394753-20887-1-git-send-email-chuhu@redhat.com

Fixes: cab5037 ("tracing/ftrace: Enable snapshot function trigger")
Fixes: 886b5b7 ("tracing: remove /debug/tracing/latency_trace")
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
[ Replaced /sys/kernel/debug/tracing with /sys/kerne/tracing ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04 06:52:07 -05:00
Linus Torvalds 75f64f68af Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
 "A selection of fixes/changes that should make it into this series.
  This contains:

   - NVMe, two merges, containing:
        - pci-e, rdma, and fc fixes
        - Device quirks

   - Fix for a badblocks leak in null_blk

   - bcache fix from Rui Hua for a race condition regression where
     -EINTR was returned to upper layers that didn't expect it.

   - Regression fix for blktrace for a bug introduced in this series.

   - blktrace cleanup for cgroup id.

   - bdi registration error handling.

   - Small series with cleanups for blk-wbt.

   - Various little fixes for typos and the like.

  Nothing earth shattering, most important are the NVMe and bcache fixes"

* 'for-linus' of git://git.kernel.dk/linux-block: (34 commits)
  nvme-pci: fix NULL pointer dereference in nvme_free_host_mem()
  nvme-rdma: fix memory leak during queue allocation
  blktrace: fix trace mutex deadlock
  nvme-rdma: Use mr pool
  nvme-rdma: Check remotely invalidated rkey matches our expected rkey
  nvme-rdma: wait for local invalidation before completing a request
  nvme-rdma: don't complete requests before a send work request has completed
  nvme-rdma: don't suppress send completions
  bcache: check return value of register_shrinker
  bcache: recover data from backing when data is clean
  bcache: Fix building error on MIPS
  bcache: add a comment in journal bucket reading
  nvme-fc: don't use bit masks for set/test_bit() numbers
  blk-wbt: fix comments typo
  blk-wbt: move wbt_clear_stat to common place in wbt_done
  blk-sysfs: remove NULL pointer checking in queue_wb_lat_store
  blk-wbt: remove duplicated setting in wbt_init
  nvme-pci: add quirk for delay before CHK RDY for WDC SN200
  block: remove useless assignment in bio_split
  null_blk: fix dev->badblocks leak
  ...
2017-12-01 08:05:45 -05:00
Yonghong Song c8c088ba0e bpf: set maximum number of attached progs to 64 for a single perf tp
cgropu+bpf prog array has a maximum number of 64 programs.
Let us apply the same limit here.

Fixes: e87c6bc385 ("bpf: permit multiple bpf attachments for a single perf event")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-01 02:56:10 +01:00
Al Viro ecf927000c ring_buffer_poll_wait() return value used as return value of ->poll()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-28 11:07:12 -05:00
Al Viro 9dd957485d ipc, kernel, mm: annotate ->poll() instances
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-27 16:20:05 -05:00
Jens Axboe 2967acbb25 blktrace: fix trace mutex deadlock
A previous commit changed the locking around registration/cleanup,
but direct callers of blk_trace_remove() were missed. This means
that if we hit the error path in setup, we will deadlock on
attempting to re-acquire the queue trace mutex.

Fixes: 1f2cac107c ("blktrace: fix unlocked access to init/start-stop/teardown")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-27 12:03:58 -07:00
Paul E. McKenney 844ccdd7dc rcu: Eliminate rcu_irq_enter_disabled()
Now that the irq path uses the rcu_nmi_{enter,exit}() algorithm,
rcu_irq_enter() and rcu_irq_exit() may be used from any context.  There is
thus no need for rcu_irq_enter_disabled() and for the checks using it.
This commit therefore eliminates rcu_irq_enter_disabled().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-27 08:42:03 -08:00
Gianluca Borello a60dd35d2e bpf: change bpf_perf_event_output arg5 type to ARG_CONST_SIZE_OR_ZERO
Commit 9fd29c08e5 ("bpf: improve verifier ARG_CONST_SIZE_OR_ZERO
semantics") relaxed the treatment of ARG_CONST_SIZE_OR_ZERO due to the way
the compiler generates optimized BPF code when checking boundaries of an
argument from C code. A typical example of this optimized code can be
generated using the bpf_perf_event_output helper when operating on variable
memory:

/* len is a generic scalar */
if (len > 0 && len <= 0x7fff)
        bpf_perf_event_output(ctx, &perf_map, 0, buf, len);

110: (79) r5 = *(u64 *)(r10 -40)
111: (bf) r1 = r5
112: (07) r1 += -1
113: (25) if r1 > 0x7ffe goto pc+6
114: (bf) r1 = r6
115: (18) r2 = 0xffff94e5f166c200
117: (b7) r3 = 0
118: (bf) r4 = r7
119: (85) call bpf_perf_event_output#25
R5 min value is negative, either use unsigned or 'var &= const'

With this code, the verifier loses track of the variable.

Replacing arg5 with ARG_CONST_SIZE_OR_ZERO is thus desirable since it
avoids this quite common case which leads to usability issues, and the
compiler generates code that the verifier can more easily test:

if (len <= 0x7fff)
        bpf_perf_event_output(ctx, &perf_map, 0, buf, len);

or

bpf_perf_event_output(ctx, &perf_map, 0, buf, len & 0x7fff);

No changes to the bpf_perf_event_output helper are necessary since it can
handle a case where size is 0, and an empty frame is pushed.

Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Gianluca Borello <g.borello@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-22 21:40:54 +01:00
Gianluca Borello 5c4e120174 bpf: change bpf_probe_read_str arg2 type to ARG_CONST_SIZE_OR_ZERO
Commit 9fd29c08e5 ("bpf: improve verifier ARG_CONST_SIZE_OR_ZERO
semantics") relaxed the treatment of ARG_CONST_SIZE_OR_ZERO due to the way
the compiler generates optimized BPF code when checking boundaries of an
argument from C code. A typical example of this optimized code can be
generated using the bpf_probe_read_str helper when operating on variable
memory:

/* len is a generic scalar */
if (len > 0 && len <= 0x7fff)
        bpf_probe_read_str(p, len, s);

251: (79) r1 = *(u64 *)(r10 -88)
252: (07) r1 += -1
253: (25) if r1 > 0x7ffe goto pc-42
254: (bf) r1 = r7
255: (79) r2 = *(u64 *)(r10 -88)
256: (bf) r8 = r4
257: (85) call bpf_probe_read_str#45
R2 min value is negative, either use unsigned or 'var &= const'

With this code, the verifier loses track of the variable.

Replacing arg2 with ARG_CONST_SIZE_OR_ZERO is thus desirable since it
avoids this quite common case which leads to usability issues, and the
compiler generates code that the verifier can more easily test:

if (len <= 0x7fff)
        bpf_probe_read_str(p, len, s);

or

bpf_probe_read_str(p, len & 0x7fff, s);

No changes to the bpf_probe_read_str helper are necessary since
strncpy_from_unsafe itself immediately returns if the size passed is 0.

Signed-off-by: Gianluca Borello <g.borello@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-22 21:40:54 +01:00
Gianluca Borello eb33f2cca4 bpf: remove explicit handling of 0 for arg2 in bpf_probe_read
Commit 9c019e2bc4 ("bpf: change helper bpf_probe_read arg2 type to
ARG_CONST_SIZE_OR_ZERO") changed arg2 type to ARG_CONST_SIZE_OR_ZERO to
simplify writing bpf programs by taking advantage of the new semantics
introduced for ARG_CONST_SIZE_OR_ZERO which allows <!NULL, 0> arguments.

In order to prevent the helper from actually passing a NULL pointer to
probe_kernel_read, which can happen when <NULL, 0> is passed to the helper,
the commit also introduced an explicit check against size == 0.

After the recent introduction of the ARG_PTR_TO_MEM_OR_NULL type,
bpf_probe_read can not receive a pair of <NULL, 0> arguments anymore, thus
the check is not needed anymore and can be removed, since probe_kernel_read
can correctly handle a <!NULL, 0> call. This also fixes the semantics of
the helper before it gets officially released and bpf programs start
relying on this check.

Fixes: 9c019e2bc4 ("bpf: change helper bpf_probe_read arg2 type to ARG_CONST_SIZE_OR_ZERO")
Signed-off-by: Gianluca Borello <g.borello@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-22 21:40:54 +01:00
Marcos Paulo de Souza 1690102de5 blktrace: Use blk_trace_bio_get_cgid inside blk_add_trace_bio
We always pass in blk_trace_bio_get_cgid(q, bio) to blk_add_trace_bio().
Since both are readily available in the function already, kill the
argument.

Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com>

Rewrote commit message.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-19 12:37:26 -07:00
Linus Torvalds 2dcd9c71c1 Tracing updates for 4.15:
- Now allow module init functions to be traced
 
  - Clean up some unused or not used by config events (saves space)
 
  - Clean up of trace histogram code
 
  - Add support for preempt and interrupt enabled/disable events
 
  - Other various clean ups
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Merge tag 'trace-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from

 - allow module init functions to be traced

 - clean up some unused or not used by config events (saves space)

 - clean up of trace histogram code

 - add support for preempt and interrupt enabled/disable events

 - other various clean ups

* tag 'trace-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (30 commits)
  tracing, thermal: Hide cpu cooling trace events when not in use
  tracing, thermal: Hide devfreq trace events when not in use
  ftrace: Kill FTRACE_OPS_FL_PER_CPU
  perf/ftrace: Small cleanup
  perf/ftrace: Fix function trace events
  perf/ftrace: Revert ("perf/ftrace: Fix double traces of perf on ftrace:function")
  tracing, dma-buf: Remove unused trace event dma_fence_annotate_wait_on
  tracing, memcg, vmscan: Hide trace events when not in use
  tracing/xen: Hide events that are not used when X86_PAE is not defined
  tracing: mark trace_test_buffer as __maybe_unused
  printk: Remove superfluous memory barriers from printk_safe
  ftrace: Clear hashes of stale ips of init memory
  tracing: Add support for preempt and irq enable/disable events
  tracing: Prepare to add preempt and irq trace events
  ftrace/kallsyms: Have /proc/kallsyms show saved mod init functions
  ftrace: Add freeing algorithm to free ftrace_mod_maps
  ftrace: Save module init functions kallsyms symbols for tracing
  ftrace: Allow module init functions to be traced
  ftrace: Add a ftrace_free_mem() function for modules to use
  tracing: Reimplement log2
  ...
2017-11-17 14:58:01 -08:00
Linus Torvalds 7c225c69f8 Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:

 - a few misc bits

 - ocfs2 updates

 - almost all of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (131 commits)
  memory hotplug: fix comments when adding section
  mm: make alloc_node_mem_map a void call if we don't have CONFIG_FLAT_NODE_MEM_MAP
  mm: simplify nodemask printing
  mm,oom_reaper: remove pointless kthread_run() error check
  mm/page_ext.c: check if page_ext is not prepared
  writeback: remove unused function parameter
  mm: do not rely on preempt_count in print_vma_addr
  mm, sparse: do not swamp log with huge vmemmap allocation failures
  mm/hmm: remove redundant variable align_end
  mm/list_lru.c: mark expected switch fall-through
  mm/shmem.c: mark expected switch fall-through
  mm/page_alloc.c: broken deferred calculation
  mm: don't warn about allocations which stall for too long
  fs: fuse: account fuse_inode slab memory as reclaimable
  mm, page_alloc: fix potential false positive in __zone_watermark_ok
  mm: mlock: remove lru_add_drain_all()
  mm, sysctl: make NUMA stats configurable
  shmem: convert shmem_init_inodecache() to void
  Unify migrate_pages and move_pages access checks
  mm, pagevec: rename pagevec drained field
  ...
2017-11-15 19:42:40 -08:00
Levin, Alexander (Sasha Levin) 4950276672 kmemcheck: remove annotations
Patch series "kmemcheck: kill kmemcheck", v2.

As discussed at LSF/MM, kill kmemcheck.

KASan is a replacement that is able to work without the limitation of
kmemcheck (single CPU, slow).  KASan is already upstream.

We are also not aware of any users of kmemcheck (or users who don't
consider KASan as a suitable replacement).

The only objection was that since KASAN wasn't supported by all GCC
versions provided by distros at that time we should hold off for 2
years, and try again.

Now that 2 years have passed, and all distros provide gcc that supports
KASAN, kill kmemcheck again for the very same reasons.

This patch (of 4):

Remove kmemcheck annotations, and calls to kmemcheck from the kernel.

[alexander.levin@verizon.com: correctly remove kmemcheck call from dma_map_sg_attrs]
  Link: http://lkml.kernel.org/r/20171012192151.26531-1-alexander.levin@verizon.com
Link: http://lkml.kernel.org/r/20171007030159.22241-2-alexander.levin@verizon.com
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tim Hansen <devtimhansen@gmail.com>
Cc: Vegard Nossum <vegardno@ifi.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:04 -08:00
Linus Torvalds 5bbcc0f595 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Highlights:

   1) Maintain the TCP retransmit queue using an rbtree, with 1GB
      windows at 100Gb this really has become necessary. From Eric
      Dumazet.

   2) Multi-program support for cgroup+bpf, from Alexei Starovoitov.

   3) Perform broadcast flooding in hardware in mv88e6xxx, from Andrew
      Lunn.

   4) Add meter action support to openvswitch, from Andy Zhou.

   5) Add a data meta pointer for BPF accessible packets, from Daniel
      Borkmann.

   6) Namespace-ify almost all TCP sysctl knobs, from Eric Dumazet.

   7) Turn on Broadcom Tags in b53 driver, from Florian Fainelli.

   8) More work to move the RTNL mutex down, from Florian Westphal.

   9) Add 'bpftool' utility, to help with bpf program introspection.
      From Jakub Kicinski.

  10) Add new 'cpumap' type for XDP_REDIRECT action, from Jesper
      Dangaard Brouer.

  11) Support 'blocks' of transformations in the packet scheduler which
      can span multiple network devices, from Jiri Pirko.

  12) TC flower offload support in cxgb4, from Kumar Sanghvi.

  13) Priority based stream scheduler for SCTP, from Marcelo Ricardo
      Leitner.

  14) Thunderbolt networking driver, from Amir Levy and Mika Westerberg.

  15) Add RED qdisc offloadability, and use it in mlxsw driver. From
      Nogah Frankel.

  16) eBPF based device controller for cgroup v2, from Roman Gushchin.

  17) Add some fundamental tracepoints for TCP, from Song Liu.

  18) Remove garbage collection from ipv6 route layer, this is a
      significant accomplishment. From Wei Wang.

  19) Add multicast route offload support to mlxsw, from Yotam Gigi"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2177 commits)
  tcp: highest_sack fix
  geneve: fix fill_info when link down
  bpf: fix lockdep splat
  net: cdc_ncm: GetNtbFormat endian fix
  openvswitch: meter: fix NULL pointer dereference in ovs_meter_cmd_reply_start
  netem: remove unnecessary 64 bit modulus
  netem: use 64 bit divide by rate
  tcp: Namespace-ify sysctl_tcp_default_congestion_control
  net: Protect iterations over net::fib_notifier_ops in fib_seq_sum()
  ipv6: set all.accept_dad to 0 by default
  uapi: fix linux/tls.h userspace compilation error
  usbnet: ipheth: prevent TX queue timeouts when device not ready
  vhost_net: conditionally enable tx polling
  uapi: fix linux/rxrpc.h userspace compilation errors
  net: stmmac: fix LPI transitioning for dwmac4
  atm: horizon: Fix irq release error
  net-sysfs: trigger netlink notification on ifalias change via sysfs
  openvswitch: Using kfree_rcu() to simplify the code
  openvswitch: Make local function ovs_nsh_key_attr_size() static
  openvswitch: Fix return value check in ovs_meter_cmd_features()
  ...
2017-11-15 11:56:19 -08:00
Linus Torvalds 9682b3dea2 Merge branch 'for-linus' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina:
 "The usual rocket-science from trivial tree for 4.15"

* 'for-linus' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
  MAINTAINERS: relinquish kconfig
  MAINTAINERS: Update my email address
  treewide: Fix typos in Kconfig
  kfifo: Fix comments
  init/Kconfig: Fix module signing document location
  misc: ibmasm: Return error on error path
  HID: logitech-hidpp: fix mistake in printk, "feeback" -> "feedback"
  MAINTAINERS: Correct path to uDraw PS3 driver
  tracing: Fix doc mistakes in trace sample
  tracing: Kconfig text fixes for CONFIG_HWLAT_TRACER
  MIPS: Alchemy: Remove reverted CONFIG_NETLINK_MMAP from db1xxx_defconfig
  mm/huge_memory.c: fixup grammar in comment
  lib/xz: Add fall-through comments to a switch statement
2017-11-15 10:14:11 -08:00
Linus Torvalds e2c5923c34 Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block
Pull core block layer updates from Jens Axboe:
 "This is the main pull request for block storage for 4.15-rc1.

  Nothing out of the ordinary in here, and no API changes or anything
  like that. Just various new features for drivers, core changes, etc.
  In particular, this pull request contains:

   - A patch series from Bart, closing the whole on blk/scsi-mq queue
     quescing.

   - A series from Christoph, building towards hidden gendisks (for
     multipath) and ability to move bio chains around.

   - NVMe
        - Support for native multipath for NVMe (Christoph).
        - Userspace notifications for AENs (Keith).
        - Command side-effects support (Keith).
        - SGL support (Chaitanya Kulkarni)
        - FC fixes and improvements (James Smart)
        - Lots of fixes and tweaks (Various)

   - bcache
        - New maintainer (Michael Lyle)
        - Writeback control improvements (Michael)
        - Various fixes (Coly, Elena, Eric, Liang, et al)

   - lightnvm updates, mostly centered around the pblk interface
     (Javier, Hans, and Rakesh).

   - Removal of unused bio/bvec kmap atomic interfaces (me, Christoph)

   - Writeback series that fix the much discussed hundreds of millions
     of sync-all units. This goes all the way, as discussed previously
     (me).

   - Fix for missing wakeup on writeback timer adjustments (Yafang
     Shao).

   - Fix laptop mode on blk-mq (me).

   - {mq,name} tupple lookup for IO schedulers, allowing us to have
     alias names. This means you can use 'deadline' on both !mq and on
     mq (where it's called mq-deadline). (me).

   - blktrace race fix, oopsing on sg load (me).

   - blk-mq optimizations (me).

   - Obscure waitqueue race fix for kyber (Omar).

   - NBD fixes (Josef).

   - Disable writeback throttling by default on bfq, like we do on cfq
     (Luca Miccio).

   - Series from Ming that enable us to treat flush requests on blk-mq
     like any other request. This is a really nice cleanup.

   - Series from Ming that improves merging on blk-mq with schedulers,
     getting us closer to flipping the switch on scsi-mq again.

   - BFQ updates (Paolo).

   - blk-mq atomic flags memory ordering fixes (Peter Z).

   - Loop cgroup support (Shaohua).

   - Lots of minor fixes from lots of different folks, both for core and
     driver code"

* 'for-4.15/block' of git://git.kernel.dk/linux-block: (294 commits)
  nvme: fix visibility of "uuid" ns attribute
  blk-mq: fixup some comment typos and lengths
  ide: ide-atapi: fix compile error with defining macro DEBUG
  blk-mq: improve tag waiting setup for non-shared tags
  brd: remove unused brd_mutex
  blk-mq: only run the hardware queue if IO is pending
  block: avoid null pointer dereference on null disk
  fs: guard_bio_eod() needs to consider partitions
  xtensa/simdisk: fix compile error
  nvme: expose subsys attribute to sysfs
  nvme: create 'slaves' and 'holders' entries for hidden controllers
  block: create 'slaves' and 'holders' entries for hidden gendisks
  nvme: also expose the namespace identification sysfs files for mpath nodes
  nvme: implement multipath access to nvme subsystems
  nvme: track shared namespaces
  nvme: introduce a nvme_ns_ids structure
  nvme: track subsystems
  block, nvme: Introduce blk_mq_req_flags_t
  block, scsi: Make SCSI quiesce and resume work reliably
  block: Add the QUEUE_FLAG_PREEMPT_ONLY request queue flag
  ...
2017-11-14 15:32:19 -08:00
Yonghong Song 9c019e2bc4 bpf: change helper bpf_probe_read arg2 type to ARG_CONST_SIZE_OR_ZERO
The helper bpf_probe_read arg2 type is changed
from ARG_CONST_SIZE to ARG_CONST_SIZE_OR_ZERO to permit
size-0 buffer. Together with newer ARG_CONST_SIZE_OR_ZERO
semantics which allows non-NULL buffer with size 0,
this allows simpler bpf programs with verifier acceptance.
The previous commit which changes ARG_CONST_SIZE_OR_ZERO semantics
has details on examples.

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14 16:20:03 +09:00
Linus Torvalds 3e2014637c Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "The main updates in this cycle were:

   - Group balancing enhancements and cleanups (Brendan Jackman)

   - Move CPU isolation related functionality into its separate
     kernel/sched/isolation.c file, with related 'housekeeping_*()'
     namespace and nomenclature et al. (Frederic Weisbecker)

   - Improve the interactive/cpu-intense fairness calculation (Josef
     Bacik)

   - Improve the PELT code and related cleanups (Peter Zijlstra)

   - Improve the logic of pick_next_task_fair() (Uladzislau Rezki)

   - Improve the RT IPI based balancing logic (Steven Rostedt)

   - Various micro-optimizations:

   - better !CONFIG_SCHED_DEBUG optimizations (Patrick Bellasi)

   - better idle loop (Cheng Jian)

   - ... plus misc fixes, cleanups and updates"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
  sched/core: Optimize sched_feat() for !CONFIG_SCHED_DEBUG builds
  sched/sysctl: Fix attributes of some extern declarations
  sched/isolation: Document isolcpus= boot parameter flags, mark it deprecated
  sched/isolation: Add basic isolcpus flags
  sched/isolation: Move isolcpus= handling to the housekeeping code
  sched/isolation: Handle the nohz_full= parameter
  sched/isolation: Introduce housekeeping flags
  sched/isolation: Split out new CONFIG_CPU_ISOLATION=y config from CONFIG_NO_HZ_FULL
  sched/isolation: Rename is_housekeeping_cpu() to housekeeping_cpu()
  sched/isolation: Use its own static key
  sched/isolation: Make the housekeeping cpumask private
  sched/isolation: Provide a dynamic off-case to housekeeping_any_cpu()
  sched/isolation, watchdog: Use housekeeping_cpumask() instead of ad-hoc version
  sched/isolation: Move housekeeping related code to its own file
  sched/idle: Micro-optimize the idle loop
  sched/isolcpus: Fix "isolcpus=" boot parameter handling when !CONFIG_CPUMASK_OFFSTACK
  x86/tsc: Append the 'tsc=' description for the 'tsc=unstable' boot parameter
  sched/rt: Simplify the IPI based RT balancing logic
  block/ioprio: Use a helper to check for RT prio
  sched/rt: Add a helper to test for a RT task
  ...
2017-11-13 13:37:52 -08:00