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24582 Commits

Author SHA1 Message Date
Linus Torvalds 160062e190 While continuing my development, I uncovered two more small bugs.
One is a race condition when enabling the snapshot function probe
 trigger. It enables the probe before allocating the snapshot, and
 if the probe triggers first, it stops tracing with a warning that
 the snapshot buffer was not allocated.
 
 The seconds is that the snapshot file should show how to use it when
 it is empty. But a bug fix from long ago broke the "is empty" test
 and the snapshot file no longer displays the help message.
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Merge tag 'trace-v4.11-rc5-5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull two more ftrace fixes from Steven Rostedt:
 "While continuing my development, I uncovered two more small bugs.

  One is a race condition when enabling the snapshot function probe
  trigger. It enables the probe before allocating the snapshot, and if
  the probe triggers first, it stops tracing with a warning that the
  snapshot buffer was not allocated.

  The seconds is that the snapshot file should show how to use it when
  it is empty. But a bug fix from long ago broke the "is empty" test and
  the snapshot file no longer displays the help message"

* tag 'trace-v4.11-rc5-5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ring-buffer: Have ring_buffer_iter_empty() return true when empty
  tracing: Allocate the snapshot buffer before enabling probe
2017-04-20 12:30:10 -07:00
Christoph Hellwig caf7df1227 block: remove the errors field from struct request
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 12:16:10 -06:00
Christoph Hellwig cee4b7ce3f blktrace: remove the unused block_rq_abort tracepoint
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 12:16:10 -06:00
David S. Miller 7b9f6da175 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
A function in kernel/bpf/syscall.c which got a bug fix in 'net'
was moved to kernel/bpf/verifier.c in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-20 10:35:33 -04:00
Thomas Gleixner 7a258ff04f Merge branch 'linus' into irq/core
Pick up upstream fixes to avoid conflicts with pending patches.
2017-04-20 16:05:13 +02:00
Keith Busch b72f8051f3 genirq/affinity: Fix calculating vectors to assign
The vectors_per_node is calculated from the remaining available vectors.
The current vector starts after pre_vectors, so we need to subtract that
from the current to properly account for the number of remaining vectors
to assign.

Fixes: 3412386b53 ("irq/affinity: Fix extra vecs calculation")
Reported-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Link: http://lkml.kernel.org/r/1492645870-13019-1-git-send-email-keith.busch@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-20 16:03:09 +02:00
Naveen N. Rao 290e307076 powerpc/kprobes: Fix handling of function offsets on ABIv2
commit 239aeba764 ("perf powerpc: Fix kprobe and kretprobe handling with
kallsyms on ppc64le") changed how we use the offset field in struct kprobe on
ABIv2. perf now offsets from the global entry point if an offset is specified
and otherwise chooses the local entry point.

Fix the same in kernel for kprobe API users. We do this by extending
kprobe_lookup_name() to accept an additional parameter to indicate the offset
specified with the kprobe registration. If offset is 0, we return the local
function entry and return the global entry point otherwise.

With:
  # cd /sys/kernel/debug/tracing/
  # echo "p _do_fork" >> kprobe_events
  # echo "p _do_fork+0x10" >> kprobe_events

before this patch:
  # cat ../kprobes/list
  c0000000000d0748  k  _do_fork+0x8    [DISABLED]
  c0000000000d0758  k  _do_fork+0x18    [DISABLED]
  c0000000000412b0  k  kretprobe_trampoline+0x0    [OPTIMIZED]

and after:
  # cat ../kprobes/list
  c0000000000d04c8  k  _do_fork+0x8    [DISABLED]
  c0000000000d04d0  k  _do_fork+0x10    [DISABLED]
  c0000000000412b0  k  kretprobe_trampoline+0x0    [OPTIMIZED]

Acked-by: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-20 23:18:55 +10:00
Naveen N. Rao 49e0b4658f kprobes: Convert kprobe_lookup_name() to a function
The macro is now pretty long and ugly on powerpc. In the light of further
changes needed here, convert it to a __weak variant to be over-ridden with a
nicer looking function.

Suggested-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-20 23:18:54 +10:00
Masami Hiramatsu a460246c70 kprobes: Skip preparing optprobe if the probe is ftrace-based
Skip preparing optprobe if the probe is ftrace-based, since anyway, it
must not be optimized (or already optimized by ftrace).

Tested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-20 23:18:54 +10:00
Myungho Jung b94bf594cf timer/sysclt: Restrict timer migration sysctl values to 0 and 1
timer_migration sysctl acts as a boolean switch, so the allowed values
should be restricted to 0 and 1.

Add the necessary extra fields to the sysctl table entry to enforce that.

[ tglx: Rewrote changelog ]

Signed-off-by: Myungho Jung <mhjungk@gmail.com>
Link: http://lkml.kernel.org/r/1492640690-3550-1-git-send-email-mhjungk@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-20 14:56:59 +02:00
Steven Rostedt (VMware) 78f7a45dac ring-buffer: Have ring_buffer_iter_empty() return true when empty
I noticed that reading the snapshot file when it is empty no longer gives a
status. It suppose to show the status of the snapshot buffer as well as how
to allocate and use it. For example:

 ># cat snapshot
 # tracer: nop
 #
 #
 # * Snapshot is allocated *
 #
 # 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')

But instead it just showed an empty buffer:

 ># cat snapshot
 # tracer: nop
 #
 # entries-in-buffer/entries-written: 0/0   #P:4
 #
 #                              _-----=> irqs-off
 #                             / _----=> need-resched
 #                            | / _---=> hardirq/softirq
 #                            || / _--=> preempt-depth
 #                            ||| /     delay
 #           TASK-PID   CPU#  ||||    TIMESTAMP  FUNCTION
 #              | |       |   ||||       |         |

What happened was that it was using the ring_buffer_iter_empty() function to
see if it was empty, and if it was, it showed the status. But that function
was returning false when it was empty. The reason was that the iter header
page was on the reader page, and the reader page was empty, but so was the
buffer itself. The check only tested to see if the iter was on the commit
page, but the commit page was no longer pointing to the reader page, but as
all pages were empty, the buffer is also.

Cc: stable@vger.kernel.org
Fixes: 651e22f270 ("ring-buffer: Always reset iterator to reader page")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-19 21:23:47 -04:00
Steven Rostedt (VMware) df62db5be2 tracing: Allocate the snapshot buffer before enabling probe
Currently the snapshot trigger enables the probe and then allocates the
snapshot. If the probe triggers before the allocation, it could cause the
snapshot to fail and turn tracing off. It's best to allocate the snapshot
buffer first, and then enable the trigger. If something goes wrong in the
enabling of the trigger, the snapshot buffer is still allocated, but it can
also be freed by the user by writting zero into the snapshot buffer file.

Also add a check of the return status of alloc_snapshot().

Cc: stable@vger.kernel.org
Fixes: 77fd5c15e3 ("tracing: Add snapshot trigger to function probes")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-19 14:19:08 -04:00
Dave Airlie 856ee92e86 Linux 4.11-rc7
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Merge tag 'v4.11-rc7' into drm-next

Backmerge Linux 4.11-rc7 from Linus tree, to fix some
conflicts that were causing problems with the rerere cache
in drm-tip.
2017-04-19 11:07:14 +10:00
Linus Torvalds 005882e53d Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
Pull sparc fixes from David Miller:
 "Two Sparc bug fixes from Daniel Jordan and Nitin Gupta"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc64: Fix hugepage page table free
  sparc64: Use LOCKDEP_SMALL, not PROVE_LOCKING_SMALL
2017-04-18 13:56:51 -07:00
Linus Torvalds 40d9018eb7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) BPF tail call handling bug fixes from Daniel Borkmann.

 2) Fix allowance of too many rx queues in sfc driver, from Bert
    Kenward.

 3) Non-loopback ipv6 packets claiming src of ::1 should be dropped,
    from Florian Westphal.

 4) Statistics requests on KSZ9031 can crash, fix from Grygorii
    Strashko.

 5) TX ring handling fixes in mediatek driver, from Sean Wang.

 6) ip_ra_control can deadlock, fix lock acquisition ordering to fix,
    from Cong WANG.

 7) Fix use after free in ip_recv_error(), from Willem de Buijn.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  bpf: fix checking xdp_adjust_head on tail calls
  bpf: fix cb access in socket filter programs on tail calls
  ipv6: drop non loopback packets claiming to originate from ::1
  net: ethernet: mediatek: fix inconsistency of port number carried in TXD
  net: ethernet: mediatek: fix inconsistency between TXD and the used buffer
  net: phy: micrel: fix crash when statistic requested for KSZ9031 phy
  net: vrf: Fix setting NLM_F_EXCL flag when adding l3mdev rule
  net: thunderx: Fix set_max_bgx_per_node for 81xx rgx
  net-timestamp: avoid use-after-free in ip_recv_error
  ipv4: fix a deadlock in ip_ra_control
  sfc: limit the number of receive queues
2017-04-18 13:24:42 -07:00
Daniel Jordan 395102db44 sparc64: Use LOCKDEP_SMALL, not PROVE_LOCKING_SMALL
CONFIG_PROVE_LOCKING_SMALL shrinks the memory usage of lockdep so the
kernel text, data, and bss fit in the required 32MB limit, but this
option is not set for every config that enables lockdep.

A 4.10 kernel fails to boot with the console output

    Kernel: Using 8 locked TLB entries for main kernel image.
    hypervisor_tlb_lock[2000000:0:8000000071c007c3:1]: errors with f
    Program terminated

with these config options

    CONFIG_LOCKDEP=y
    CONFIG_LOCK_STAT=y
    CONFIG_PROVE_LOCKING=n

To fix, rename CONFIG_PROVE_LOCKING_SMALL to CONFIG_LOCKDEP_SMALL, and
enable this option with CONFIG_LOCKDEP=y so we get the reduced memory
usage every time lockdep is turned on.

Tested that CONFIG_LOCKDEP_SMALL is set to 'y' if and only if
CONFIG_LOCKDEP is set to 'y'.  When other lockdep-related config options
that select CONFIG_LOCKDEP are enabled (e.g. CONFIG_LOCK_STAT or
CONFIG_PROVE_LOCKING), verified that CONFIG_LOCKDEP_SMALL is also
enabled.

Fixes: e6b5f1be7a ("config: Adding the new config parameter CONFIG_PROVE_LOCKING_SMALL for sparc")
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Babu Moger <babu.moger@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-18 13:11:07 -07:00
Steven Rostedt (VMware) ec19b85913 ftrace: Move the probe function into the tracing directory
As nothing outside the tracing directory uses the function probes mechanism,
I'm moving the prototypes out of the include/linux/ftrace.h and into the
local kernel/trace/trace.h header. I plan on making them hook to the
trace_array structure which is local to kernel/trace, and I do not want to
expose it to the rest of the kernel. This requires that the probe functions
must also be local to tracing. But luckily nothing else uses them.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-18 13:49:59 -04:00
Linus Torvalds 0bad6d7e93 Namhyung Kim discovered a use after free bug. It has to do with adding
a pid filter to function tracing in an instance, and then freeing
 the instance.
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Merge tag 'trace-v4.11-rc5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull ftrace fix from Steven Rostedt:
 "Namhyung Kim discovered a use after free bug. It has to do with adding
  a pid filter to function tracing in an instance, and then freeing the
  instance"

* tag 'trace-v4.11-rc5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace: Fix function pid filter on instances
2017-04-18 09:31:51 -07:00
Baoquan He f51b17c8d9 boot/param: Move next_arg() function to lib/cmdline.c for later reuse
next_arg() will be used to parse boot parameters in the x86/boot/compressed code,
so move it to lib/cmdline.c for better code reuse.

No change in functionality.

Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Cc: Jens Axboe <axboe@fb.com>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Johannes Berg <johannes.berg@intel.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dan.j.williams@intel.com
Cc: dave.jiang@intel.com
Cc: dyoung@redhat.com
Cc: keescook@chromium.org
Cc: zijun_hu <zijun_hu@htc.com>
Link: http://lkml.kernel.org/r/1492436099-4017-2-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-18 10:37:13 +02:00
Namhyung Kim 1e10486ffe ftrace: Add 'function-fork' trace option
The function-fork option is same as event-fork that it tracks task
fork/exit and set the pid filter properly.  This can be useful if user
wants to trace selected tasks including their children only.

Link: http://lkml.kernel.org/r/20170417024430.21194-3-namhyung@kernel.org

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-17 17:13:00 -04:00
Namhyung Kim d879d0b8c1 ftrace: Fix function pid filter on instances
When function tracer has a pid filter, it adds a probe to sched_switch
to track if current task can be ignored.  The probe checks the
ftrace_ignore_pid from current tr to filter tasks.  But it misses to
delete the probe when removing an instance so that it can cause a crash
due to the invalid tr pointer (use-after-free).

This is easily reproducible with the following:

  # cd /sys/kernel/debug/tracing
  # mkdir instances/buggy
  # echo $$ > instances/buggy/set_ftrace_pid
  # rmdir instances/buggy

  ============================================================================
  BUG: KASAN: use-after-free in ftrace_filter_pid_sched_switch_probe+0x3d/0x90
  Read of size 8 by task kworker/0:1/17
  CPU: 0 PID: 17 Comm: kworker/0:1 Tainted: G    B           4.11.0-rc3  #198
  Call Trace:
   dump_stack+0x68/0x9f
   kasan_object_err+0x21/0x70
   kasan_report.part.1+0x22b/0x500
   ? ftrace_filter_pid_sched_switch_probe+0x3d/0x90
   kasan_report+0x25/0x30
   __asan_load8+0x5e/0x70
   ftrace_filter_pid_sched_switch_probe+0x3d/0x90
   ? fpid_start+0x130/0x130
   __schedule+0x571/0xce0
   ...

To fix it, use ftrace_clear_pids() to unregister the probe.  As
instance_rmdir() already updated ftrace codes, it can just free the
filter safely.

Link: http://lkml.kernel.org/r/20170417024430.21194-2-namhyung@kernel.org

Fixes: 0c8916c342 ("tracing: Add rmdir to remove multibuffer instances")
Cc: Ingo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-17 16:44:23 -04:00
Daniel Borkmann c2002f9837 bpf: fix checking xdp_adjust_head on tail calls
Commit 17bedab272 ("bpf: xdp: Allow head adjustment in XDP prog")
added the xdp_adjust_head bit to the BPF prog in order to tell drivers
that the program that is to be attached requires support for the XDP
bpf_xdp_adjust_head() helper such that drivers not supporting this
helper can reject the program. There are also drivers that do support
the helper, but need to check for xdp_adjust_head bit in order to move
packet metadata prepended by the firmware away for making headroom.

For these cases, the current check for xdp_adjust_head bit is insufficient
since there can be cases where the program itself does not use the
bpf_xdp_adjust_head() helper, but tail calls into another program that
uses bpf_xdp_adjust_head(). As such, the xdp_adjust_head bit is still
set to 0. Since the first program has no control over which program it
calls into, we need to assume that bpf_xdp_adjust_head() helper is used
upon tail calls. Thus, for the very same reasons in cb_access, set the
xdp_adjust_head bit to 1 when the main program uses tail calls.

Fixes: 17bedab272 ("bpf: xdp: Allow head adjustment in XDP prog")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-17 15:51:57 -04:00
Daniel Borkmann 6b1bb01bcc bpf: fix cb access in socket filter programs on tail calls
Commit ff936a04e5 ("bpf: fix cb access in socket filter programs")
added a fix for socket filter programs such that in i) AF_PACKET the
20 bytes of skb->cb[] area gets zeroed before use in order to not leak
data, and ii) socket filter programs attached to TCP/UDP sockets need
to save/restore these 20 bytes since they are also used by protocol
layers at that time.

The problem is that bpf_prog_run_save_cb() and bpf_prog_run_clear_cb()
only look at the actual attached program to determine whether to zero
or save/restore the skb->cb[] parts. There can be cases where the
actual attached program does not access the skb->cb[], but the program
tail calls into another program which does access this area. In such
a case, the zero or save/restore is currently not performed.

Since the programs we tail call into are unknown at verification time
and can dynamically change, we need to assume that whenever the attached
program performs a tail call, that later programs could access the
skb->cb[], and therefore we need to always set cb_access to 1.

Fixes: ff936a04e5 ("bpf: fix cb access in socket filter programs")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-17 15:51:57 -04:00
Steven Rostedt (VMware) b980b117c9 tracing: Have the trace_event benchmark thread call cond_resched_rcu_qs()
The trace_event benchmark thread runs in kernel space in an infinite loop
while also calling cond_resched() in case anything else wants to schedule
in. Unfortunately, on a PREEMPT kernel, that makes it a nop, in which case,
this will never voluntarily schedule. That will cause synchronize_rcu_tasks()
to forever block on this thread, while it is running.

This is exactly what cond_resched_rcu_qs() is for. Use that instead.

Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-17 15:21:19 -04:00
Martin KaFai Lau 695ba2651a bpf: lru: Lower the PERCPU_NR_SCANS from 16 to 4
After doing map_perf_test with a much bigger
BPF_F_NO_COMMON_LRU map, the perf report shows a
lot of time spent in rotating the inactive list (i.e.
__bpf_lru_list_rotate_inactive):
> map_perf_test 32 8 10000 1000000 | awk '{sum += $3}END{print sum}'
19644783 (19M/s)
> map_perf_test 32 8 10000000 10000000 |  awk '{sum += $3}END{print sum}'
6283930 (6.28M/s)

By inactive, it usually means the element is not in cache.  Hence,
there is a need to tune the PERCPU_NR_SCANS value.

This patch finds a better number of elements to
scan during each list rotation.  The PERCPU_NR_SCANS (which
is defined the same as PERCPU_FREE_TARGET) decreases
from 16 elements to 4 elements.  This change only
affects the BPF_F_NO_COMMON_LRU map.

The test_lru_dist does not show meaningful difference
between 16 and 4.  Our production L4 load balancer which uses
the LRU map for conntrack-ing also shows little change in cache
hit rate.  Since both benchmark and production data show no
cache-hit difference, PERCPU_NR_SCANS is lowered from 16 to 4.
We can consider making it configurable if we find a usecase
later that shows another value works better and/or use
a different rotation strategy.

After this change:
> map_perf_test 32 8 10000000 10000000 |  awk '{sum += $3}END{print sum}'
9240324 (9.2M/s)

i.e. 6.28M/s -> 9.2M/s

The test_lru_dist has not shown meaningful difference:
> test_lru_dist zipf.100k.a1_01.out 4000 1:
nr_misses: 31575 (Before) vs 31566 (After)

> test_lru_dist zipf.100k.a0_01.out 40000 1
nr_misses: 67036 (Before) vs 67031 (After)

Signed-off-by: Martin KaFai Lau <kafai@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>
2017-04-17 13:55:52 -04:00
Rafael J. Wysocki 1b72e7fd30 cpufreq: schedutil: Use policy-dependent transition delays
Make the schedutil governor take the initial (default) value of the
rate_limit_us sysfs attribute from the (new) transition_delay_us
policy parameter (to be set by the scaling driver).

That will allow scaling drivers to make schedutil use smaller default
values of rate_limit_us and reduce the default average time interval
between consecutive frequency changes.

Make intel_pstate set transition_delay_us to 500.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2017-04-17 18:37:27 +02:00
Steven Rostedt (VMware) fcdc712579 ftrace: Fix indexing of t_hash_start() from t_next()
t_hash_start() does not increment *pos, where as t_next() must. But when
t_next() does increment *pos, it must still pass in the original *pos to
t_hash_start() otherwise it will skip the first instance:

 # cd /sys/kernel/debug/tracing
 # echo schedule:traceoff > set_ftrace_filter
 # echo do_IRQ:traceoff > set_ftrace_filter
 # echo call_rcu > set_ftrace_filter
 # cat set_ftrace_filter
call_rcu
schedule:traceoff:unlimited
do_IRQ:traceoff:unlimited

The above called t_hash_start() from t_start() as there was only one
function (call_rcu), but if we add another function:

 # echo xfrm_policy_destroy_rcu >> set_ftrace_filter
 # cat set_ftrace_filter
call_rcu
xfrm_policy_destroy_rcu
do_IRQ:traceoff:unlimited

The "schedule:traceoff" disappears.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-17 10:22:29 -04:00
Eric W. Biederman 01a2197485 posix-timers: Correct sanity check in posix_cpu_nsleep
CPUCLOCK_PID(which_clock) is a pid value from userspace so compare it
against task_pid_vnr, not current->pid.  As task_pid_vnr is in the tasks
pid value in the tasks pid namespace, and current->pid is in the
initial pid namespace.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2017-04-16 23:42:50 -05:00
Josh Poimboeuf 77f8f39a2e livepatch: add missing printk newlines
Add missing newlines to some pr_err() strings.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Jessica Yu <jeyu@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2017-04-16 22:48:05 +02:00
Linus Torvalds 11c994d9a5 Merge branch 'for-4.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fix from Tejun Heo:
 "Unfortunately, the commit to fix the cgroup mount race in the previous
  pull request can lead to hangs.

  The original bug has been around for a while and isn't too likely to
  be triggered in usual use cases. Revert the commit for now"

* 'for-4.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  Revert "cgroup: avoid attaching a cgroup root to two different superblocks"
2017-04-16 11:48:10 -07:00
Linus Torvalds 48538861b9 While rewriting the function probe code, I stumbled over a long standing
bug. This bug has been there sinc function tracing was added way back
 when. But my new development depends on this bug being fixed, and it
 should be fixed regardless as it causes ftrace to disable itself when
 triggered, and a reboot is required to enable it again.
 
 The bug is that the function probe does not disable itself properly
 if there's another probe of its type still enabled. For example:
 
      # cd /sys/kernel/debug/tracing
      # echo schedule:traceoff > set_ftrace_filter
      # echo do_IRQ:traceoff > set_ftrace_filter
      # echo \!do_IRQ:traceoff > /debug/tracing/set_ftrace_filter
      # echo do_IRQ:traceoff > set_ftrace_filter
 
 The above registers two traceoff probes (one for schedule and one for
 do_IRQ, and then removes do_IRQ. But since there still exists one for
 schedule, it is not done properly. When adding do_IRQ back, the breakage
 in the accounting is noticed by the ftrace self tests, and it causes
 a warning and disables ftrace.
 -----BEGIN PGP SIGNATURE-----
 
 iQExBAABCAAbBQJY8ovvFBxyb3N0ZWR0QGdvb2RtaXMub3JnAAoJEMm5BfJq2Y3L
 nkAH/jfsXUWIbZ6J0A7+nmGiBdIVwLwG0ZOJClcxjnCSpsNs+FO/0w6ragtIYCi2
 Km+0s/slA5GOddG4Miga/dhtxGhDosyXnxqC+4GmD0maqJGLweJLbmiQ1xhra0hr
 XGDI+SXHM/n22zVkFEbkGXgxMvOHeR+X/sREZo3XmoXRLbc1QVtTEe/8TdlLXwE5
 5Fs07xSQqx4TS7oBxIjipHnbHL/gIktEo0HiEmq73++r42MztIMYZPoV+cXuim37
 C6xO4PxfPN0aRh9W5gdiMnbv6lummVBNQXwpMya0vTbxz/9WeUex8c+lcInQUJgA
 FhQWKaCGyi0UK4Pa2Pz/Dmxuti0=
 =LYLo
 -----END PGP SIGNATURE-----

Merge tag 'trace-v4.11-rc5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull ftrace fix from Steven Rostedt:
 "While rewriting the function probe code, I stumbled over a long
  standing bug. This bug has been there sinc function tracing was added
  way back when. But my new development depends on this bug being fixed,
  and it should be fixed regardless as it causes ftrace to disable
  itself when triggered, and a reboot is required to enable it again.

  The bug is that the function probe does not disable itself properly if
  there's another probe of its type still enabled. For example:

     # cd /sys/kernel/debug/tracing
     # echo schedule:traceoff > set_ftrace_filter
     # echo do_IRQ:traceoff > set_ftrace_filter
     # echo \!do_IRQ:traceoff > /debug/tracing/set_ftrace_filter
     # echo do_IRQ:traceoff > set_ftrace_filter

  The above registers two traceoff probes (one for schedule and one for
  do_IRQ, and then removes do_IRQ.

  But since there still exists one for schedule, it is not done
  properly. When adding do_IRQ back, the breakage in the accounting is
  noticed by the ftrace self tests, and it causes a warning and disables
  ftrace"

* tag 'trace-v4.11-rc5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace: Fix removing of second function probe
2017-04-16 10:01:34 -07:00
Tejun Heo 330c418638 Revert "cgroup: avoid attaching a cgroup root to two different superblocks"
This reverts commit bfb0b80db5.

Andrei reports CRIU test hangs with the patch applied.  The bug fixed
by the patch isn't too likely to trigger in actual uses.  Revert the
patch for now.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Andrei Vagin <avagin@virtuozzo.com>
Link: http://lkml.kernel.org/r/20170414232737.GC20350@outlook.office365.com
2017-04-16 23:17:37 +09:00
David S. Miller 6b6cbc1471 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts were simply overlapping changes.  In the net/ipv4/route.c
case the code had simply moved around a little bit and the same fix
was made in both 'net' and 'net-next'.

In the net/sched/sch_generic.c case a fix in 'net' happened at
the same time that a new argument was added to qdisc_hash_add().

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-15 21:16:30 -04:00
Steven Rostedt (VMware) acceb72e90 ftrace: Fix removing of second function probe
When two function probes are added to set_ftrace_filter, and then one of
them is removed, the update to the function locations is not performed, and
the record keeping of the function states are corrupted, and causes an
ftrace_bug() to occur.

This is easily reproducable by adding two probes, removing one, and then
adding it back again.

 # cd /sys/kernel/debug/tracing
 # echo schedule:traceoff > set_ftrace_filter
 # echo do_IRQ:traceoff > set_ftrace_filter
 # echo \!do_IRQ:traceoff > /debug/tracing/set_ftrace_filter
 # echo do_IRQ:traceoff > set_ftrace_filter

Causes:
 ------------[ cut here ]------------
 WARNING: CPU: 2 PID: 1098 at kernel/trace/ftrace.c:2369 ftrace_get_addr_curr+0x143/0x220
 Modules linked in: [...]
 CPU: 2 PID: 1098 Comm: bash Not tainted 4.10.0-test+ #405
 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v02.05 05/07/2012
 Call Trace:
  dump_stack+0x68/0x9f
  __warn+0x111/0x130
  ? trace_irq_work_interrupt+0xa0/0xa0
  warn_slowpath_null+0x1d/0x20
  ftrace_get_addr_curr+0x143/0x220
  ? __fentry__+0x10/0x10
  ftrace_replace_code+0xe3/0x4f0
  ? ftrace_int3_handler+0x90/0x90
  ? printk+0x99/0xb5
  ? 0xffffffff81000000
  ftrace_modify_all_code+0x97/0x110
  arch_ftrace_update_code+0x10/0x20
  ftrace_run_update_code+0x1c/0x60
  ftrace_run_modify_code.isra.48.constprop.62+0x8e/0xd0
  register_ftrace_function_probe+0x4b6/0x590
  ? ftrace_startup+0x310/0x310
  ? debug_lockdep_rcu_enabled.part.4+0x1a/0x30
  ? update_stack_state+0x88/0x110
  ? ftrace_regex_write.isra.43.part.44+0x1d3/0x320
  ? preempt_count_sub+0x18/0xd0
  ? mutex_lock_nested+0x104/0x800
  ? ftrace_regex_write.isra.43.part.44+0x1d3/0x320
  ? __unwind_start+0x1c0/0x1c0
  ? _mutex_lock_nest_lock+0x800/0x800
  ftrace_trace_probe_callback.isra.3+0xc0/0x130
  ? func_set_flag+0xe0/0xe0
  ? __lock_acquire+0x642/0x1790
  ? __might_fault+0x1e/0x20
  ? trace_get_user+0x398/0x470
  ? strcmp+0x35/0x60
  ftrace_trace_onoff_callback+0x48/0x70
  ftrace_regex_write.isra.43.part.44+0x251/0x320
  ? match_records+0x420/0x420
  ftrace_filter_write+0x2b/0x30
  __vfs_write+0xd7/0x330
  ? do_loop_readv_writev+0x120/0x120
  ? locks_remove_posix+0x90/0x2f0
  ? do_lock_file_wait+0x160/0x160
  ? __lock_is_held+0x93/0x100
  ? rcu_read_lock_sched_held+0x5c/0xb0
  ? preempt_count_sub+0x18/0xd0
  ? __sb_start_write+0x10a/0x230
  ? vfs_write+0x222/0x240
  vfs_write+0xef/0x240
  SyS_write+0xab/0x130
  ? SyS_read+0x130/0x130
  ? trace_hardirqs_on_caller+0x182/0x280
  ? trace_hardirqs_on_thunk+0x1a/0x1c
  entry_SYSCALL_64_fastpath+0x18/0xad
 RIP: 0033:0x7fe61c157c30
 RSP: 002b:00007ffe87890258 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
 RAX: ffffffffffffffda RBX: ffffffff8114a410 RCX: 00007fe61c157c30
 RDX: 0000000000000010 RSI: 000055814798f5e0 RDI: 0000000000000001
 RBP: ffff8800c9027f98 R08: 00007fe61c422740 R09: 00007fe61ca53700
 R10: 0000000000000073 R11: 0000000000000246 R12: 0000558147a36400
 R13: 00007ffe8788f160 R14: 0000000000000024 R15: 00007ffe8788f15c
  ? trace_hardirqs_off_caller+0xc0/0x110
 ---[ end trace 99fa09b3d9869c2c ]---
 Bad trampoline accounting at: ffffffff81cc3b00 (do_IRQ+0x0/0x150)

Cc: stable@vger.kernel.org
Fixes: 59df055f19 ("ftrace: trace different functions with a different tracer")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-15 17:04:37 -04:00
Darren Hart (VMware) 38fcd06e9b futex: Clarify mark_wake_futex memory barrier usage
Clarify the scenario described in mark_wake_futex requiring the
smp_store_release(). Update the comment to explicitly refer to the
plist_del now under __unqueue_futex() (previously plist_del was in the
same function as the comment).

Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170414223138.GA4222@fury
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-15 16:03:46 +02:00
Hans de Goede 382bd4de61 genirq: Use irqd_get_trigger_type to compare the trigger type for shared IRQs
When requesting a shared irq with IRQF_TRIGGER_NONE then the irqaction
flags get filled with the trigger type from the irq_data:

        if (!(new->flags & IRQF_TRIGGER_MASK))
                new->flags |= irqd_get_trigger_type(&desc->irq_data);

On the first setup_irq() the trigger type in irq_data is NONE when the
above code executes, then the irq is started up for the first time and
then the actual trigger type gets established, but that's too late to fix
up new->flags.

When then a second user of the irq requests the irq with IRQF_TRIGGER_NONE
its irqaction's triggertype gets set to the actual trigger type and the
following check fails:

        if (!((old->flags ^ new->flags) & IRQF_TRIGGER_MASK))

Resulting in the request_irq failing with -EBUSY even though both
users requested the irq with IRQF_SHARED | IRQF_TRIGGER_NONE

Fix this by comparing the new irqaction's trigger type to the trigger type
stored in the irq_data which correctly reflects the actual trigger type
being used for the irq.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Link: http://lkml.kernel.org/r/20170415100831.17073-1-hdegoede@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-15 15:42:43 +02:00
Thomas Gleixner d1b25279c1 irqchip updates for v4.12
- Unify gemini and moxa irqchips under the faraday banner
 - Extend mtk-sysirq to deal with multiple MMIO regions
 - ACPI/IORT support for GICv3 ITS platform MSI
 - ACPI support for mbigen
 - Add mtk-cirq wakeup interrupt controller driver
 - Atmel aic5 suspend support
 - Allow GPCv2 to be probed both as an irqchip and a device
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Merge tag 'irqchip-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core

Pull irqchip updates from Marc Zyngier

 - Unify gemini and moxa irqchips under the faraday banner
 - Extend mtk-sysirq to deal with multiple MMIO regions
 - ACPI/IORT support for GICv3 ITS platform MSI
 - ACPI support for mbigen
 - Add mtk-cirq wakeup interrupt controller driver
 - Atmel aic5 suspend support
 - Allow GPCv2 to be probed both as an irqchip and a device
2017-04-15 15:31:11 +02:00
Thomas Gleixner 0e8d6a9336 workqueue: Provide work_on_cpu_safe()
work_on_cpu() is not protected against CPU hotplug. For code which requires
to be either executed on an online CPU or to fail if the CPU is not
available the callsite would have to protect against CPU hotplug.

Provide a function which does get/put_online_cpus() around the call to
work_on_cpu() and fails the call with -ENODEV if the target CPU is not
online.

Preparatory patch to convert several racy task affinity manipulations.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Len Brown <lenb@kernel.org>
Link: http://lkml.kernel.org/r/20170412201042.262610721@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-15 12:20:53 +02:00
Linus Torvalds 7e703eccf0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:
 "Things seem to be settling down as far as networking is concerned,
  let's hope this trend continues...

   1) Add iov_iter_revert() and use it to fix the behavior of
      skb_copy_datagram_msg() et al., from Al Viro.

   2) Fix the protocol used in the synthetic SKB we cons up for the
      purposes of doing a simulated route lookup for RTM_GETROUTE
      requests. From Florian Larysch.

   3) Don't add noop_qdisc to the per-device qdisc hashes, from Cong
      Wang.

   4) Don't call netdev_change_features with the team lock held, from
      Xin Long.

   5) Revert TCP F-RTO extension to catch more spurious timeouts because
      it interacts very badly with some middle-boxes. From Yuchung
      Cheng.

   6) Fix the loss of error values in l2tp {s,g}etsockopt calls, from
      Guillaume Nault.

   7) ctnetlink uses bit positions where it should be using bit masks,
      fix from Liping Zhang.

   8) Missing RCU locking in netfilter helper code, from Gao Feng.

   9) Avoid double frees and use-after-frees in tcp_disconnect(), from
      Eric Dumazet.

  10) Don't do a changelink before we register the netdevice in
      bridging, from Ido Schimmel.

  11) Lock the ipv6 device address list properly, from Rabin Vincent"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (29 commits)
  netfilter: ipt_CLUSTERIP: Fix wrong conntrack netns refcnt usage
  netfilter: nft_hash: do not dump the auto generated seed
  drivers: net: usb: qmi_wwan: add QMI_QUIRK_SET_DTR for Telit PID 0x1201
  ipv6: Fix idev->addr_list corruption
  net: xdp: don't export dev_change_xdp_fd()
  bridge: netlink: register netdevice before executing changelink
  bridge: implement missing ndo_uninit()
  bpf: reference may_access_skb() from __bpf_prog_run()
  tcp: clear saved_syn in tcp_disconnect()
  netfilter: nf_ct_expect: use proper RCU list traversal/update APIs
  netfilter: ctnetlink: skip dumping expect when nfct_help(ct) is NULL
  netfilter: make it safer during the inet6_dev->addr_list traversal
  netfilter: ctnetlink: make it safer when checking the ct helper name
  netfilter: helper: Add the rcu lock when call __nf_conntrack_helper_find
  netfilter: ctnetlink: using bit to represent the ct event
  netfilter: xt_TCPMSS: add more sanity tests on tcph->doff
  net: tcp: Increase TCP_MIB_OUTRSTS even though fail to alloc skb
  l2tp: don't mask errors in pppol2tp_getsockopt()
  l2tp: don't mask errors in pppol2tp_setsockopt()
  tcp: restrict F-RTO to work-around broken middle-boxes
  ...
2017-04-14 17:38:24 -07:00
Linus Torvalds d295917a47 Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
 "The irq department provides:

   - two fixes for the CPU affinity spread infrastructure to prevent
     unbalanced spreading in corner cases which leads to horrible
     performance, because interrupts are rather aggregated than spread

   - add a missing spinlock initializer in the imx-gpcv2 init code"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/irq-imx-gpcv2: Fix spinlock initialization
  irq/affinity: Fix extra vecs calculation
  irq/affinity: Fix CPU spread for unbalanced nodes
2017-04-14 16:57:14 -07:00
Steven Rostedt (VMware) 82cc4fc2e7 ftrace: Fix removing of second function probe
When two function probes are added to set_ftrace_filter, and then one of
them is removed, the update to the function locations is not performed, and
the record keeping of the function states are corrupted, and causes an
ftrace_bug() to occur.

This is easily reproducable by adding two probes, removing one, and then
adding it back again.

 # cd /sys/kernel/debug/tracing
 # echo schedule:traceoff > set_ftrace_filter
 # echo do_IRQ:traceoff > set_ftrace_filter
 # echo \!do_IRQ:traceoff > /debug/tracing/set_ftrace_filter
 # echo do_IRQ:traceoff > set_ftrace_filter

Causes:
 ------------[ cut here ]------------
 WARNING: CPU: 2 PID: 1098 at kernel/trace/ftrace.c:2369 ftrace_get_addr_curr+0x143/0x220
 Modules linked in: [...]
 CPU: 2 PID: 1098 Comm: bash Not tainted 4.10.0-test+ #405
 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v02.05 05/07/2012
 Call Trace:
  dump_stack+0x68/0x9f
  __warn+0x111/0x130
  ? trace_irq_work_interrupt+0xa0/0xa0
  warn_slowpath_null+0x1d/0x20
  ftrace_get_addr_curr+0x143/0x220
  ? __fentry__+0x10/0x10
  ftrace_replace_code+0xe3/0x4f0
  ? ftrace_int3_handler+0x90/0x90
  ? printk+0x99/0xb5
  ? 0xffffffff81000000
  ftrace_modify_all_code+0x97/0x110
  arch_ftrace_update_code+0x10/0x20
  ftrace_run_update_code+0x1c/0x60
  ftrace_run_modify_code.isra.48.constprop.62+0x8e/0xd0
  register_ftrace_function_probe+0x4b6/0x590
  ? ftrace_startup+0x310/0x310
  ? debug_lockdep_rcu_enabled.part.4+0x1a/0x30
  ? update_stack_state+0x88/0x110
  ? ftrace_regex_write.isra.43.part.44+0x1d3/0x320
  ? preempt_count_sub+0x18/0xd0
  ? mutex_lock_nested+0x104/0x800
  ? ftrace_regex_write.isra.43.part.44+0x1d3/0x320
  ? __unwind_start+0x1c0/0x1c0
  ? _mutex_lock_nest_lock+0x800/0x800
  ftrace_trace_probe_callback.isra.3+0xc0/0x130
  ? func_set_flag+0xe0/0xe0
  ? __lock_acquire+0x642/0x1790
  ? __might_fault+0x1e/0x20
  ? trace_get_user+0x398/0x470
  ? strcmp+0x35/0x60
  ftrace_trace_onoff_callback+0x48/0x70
  ftrace_regex_write.isra.43.part.44+0x251/0x320
  ? match_records+0x420/0x420
  ftrace_filter_write+0x2b/0x30
  __vfs_write+0xd7/0x330
  ? do_loop_readv_writev+0x120/0x120
  ? locks_remove_posix+0x90/0x2f0
  ? do_lock_file_wait+0x160/0x160
  ? __lock_is_held+0x93/0x100
  ? rcu_read_lock_sched_held+0x5c/0xb0
  ? preempt_count_sub+0x18/0xd0
  ? __sb_start_write+0x10a/0x230
  ? vfs_write+0x222/0x240
  vfs_write+0xef/0x240
  SyS_write+0xab/0x130
  ? SyS_read+0x130/0x130
  ? trace_hardirqs_on_caller+0x182/0x280
  ? trace_hardirqs_on_thunk+0x1a/0x1c
  entry_SYSCALL_64_fastpath+0x18/0xad
 RIP: 0033:0x7fe61c157c30
 RSP: 002b:00007ffe87890258 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
 RAX: ffffffffffffffda RBX: ffffffff8114a410 RCX: 00007fe61c157c30
 RDX: 0000000000000010 RSI: 000055814798f5e0 RDI: 0000000000000001
 RBP: ffff8800c9027f98 R08: 00007fe61c422740 R09: 00007fe61ca53700
 R10: 0000000000000073 R11: 0000000000000246 R12: 0000558147a36400
 R13: 00007ffe8788f160 R14: 0000000000000024 R15: 00007ffe8788f15c
  ? trace_hardirqs_off_caller+0xc0/0x110
 ---[ end trace 99fa09b3d9869c2c ]---
 Bad trampoline accounting at: ffffffff81cc3b00 (do_IRQ+0x0/0x150)

Cc: stable@vger.kernel.org
Fixes: 59df055f19 ("ftrace: trace different functions with a different tracer")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-14 17:54:22 -04:00
Deepa Dinamani ad19638463 time: Change k_clock nsleep() to use timespec64
struct timespec is not y2038 safe on 32 bit machines.  Replace uses of
struct timespec with struct timespec64 in the kernel.

The syscall interfaces themselves will be changed in a separate series.

Note that the restart_block parameter for nanosleep has also been left
unchanged and will be part of syscall series noted above.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: y2038@lists.linaro.org
Cc: john.stultz@linaro.org
Cc: arnd@arndb.de
Link: http://lkml.kernel.org/r/1490555058-4603-8-git-send-email-deepa.kernel@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-14 21:49:56 +02:00
Deepa Dinamani 5f252b3256 time: Change k_clock timer_set() and timer_get() to use timespec64
struct timespec is not y2038 safe on 32 bit machines.  Replace uses of
struct timespec with struct timespec64 in the kernel.

struct itimerspec internally uses struct timespec.  Use struct itimerspec64
which uses struct timespec64.

The syscall interfaces themselves will be changed in a separate series.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: y2038@lists.linaro.org
Cc: john.stultz@linaro.org
Cc: arnd@arndb.de
Link: http://lkml.kernel.org/r/1490555058-4603-7-git-send-email-deepa.kernel@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-14 21:49:56 +02:00
Deepa Dinamani 0fe6afe383 time: Change k_clock clock_set() to use timespec64
struct timespec is not y2038 safe on 32 bit machines.  Replace uses of
struct timespec with struct timespec64 in the kernel.

The syscall interfaces themselves will be changed in a separate series.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: y2038@lists.linaro.org
Cc: john.stultz@linaro.org
Cc: arnd@arndb.de
Link: http://lkml.kernel.org/r/1490555058-4603-6-git-send-email-deepa.kernel@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-14 21:49:56 +02:00
Deepa Dinamani d2e3e0ca5d time: Change k_clock clock_getres() to use timespec64
struct timespec is not y2038 safe on 32 bit machines.  Replace uses of
struct timespec with struct timespec64 in the kernel. The syscall
interfaces themselves will be changed in a separate series.

The clock_getres() interface has also been changed to use timespec64 even
though this particular interface is not affected by the y2038 problem. This
helps verification for internal kernel code for y2038 readiness by getting
rid of time_t/ timeval/ timespec completely.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: y2038@lists.linaro.org
Cc: john.stultz@linaro.org
Cc: arnd@arndb.de
Link: http://lkml.kernel.org/r/1490555058-4603-5-git-send-email-deepa.kernel@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-14 21:49:55 +02:00
Deepa Dinamani 3c9c12f4b4 time: Change k_clock clock_get() to use timespec64
struct timespec is not y2038 safe on 32 bit machines.  Replace uses of
struct timespec with struct timespec64 in the kernel.

The syscall interfaces themselves will be changed in a separate series.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: y2038@lists.linaro.org
Cc: john.stultz@linaro.org
Cc: arnd@arndb.de
Link: http://lkml.kernel.org/r/1490555058-4603-4-git-send-email-deepa.kernel@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-14 21:49:55 +02:00
Deepa Dinamani d340266e19 time: Change posix clocks ops interfaces to use timespec64
struct timespec is not y2038 safe on 32 bit machines.

The posix clocks apis use struct timespec directly and through struct
itimerspec.

Replace the posix clock interfaces to use struct timespec64 and struct
itimerspec64 instead.  Also fix up their implementations accordingly.

Note that the clock_getres() interface has also been changed to use
timespec64 even though this particular interface is not affected by the
y2038 problem. This helps verification for internal kernel code for y2038
readiness by getting rid of time_t/ timeval/ timespec.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: arnd@arndb.de
Cc: y2038@lists.linaro.org
Cc: netdev@vger.kernel.org
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: john.stultz@linaro.org
Link: http://lkml.kernel.org/r/1490555058-4603-3-git-send-email-deepa.kernel@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-14 21:49:54 +02:00
Deepa Dinamani 2ac00f17b2 time: Delete do_sys_setimeofday()
struct timespec is not y2038 safe on 32 bit machines and needs to be
replaced with struct timespec64.

do_sys_timeofday() is just a wrapper function.  Replace all calls to this
function with direct calls to do_sys_timeofday64() instead and delete
do_sys_timeofday().

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: y2038@lists.linaro.org
Cc: john.stultz@linaro.org
Cc: arnd@arndb.de
Cc: linux-alpha@vger.kernel.org
Link: http://lkml.kernel.org/r/1490555058-4603-2-git-send-email-deepa.kernel@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-14 21:49:54 +02:00
Matthias Kaehlcke d170fe7dd9 genirq: Use cpumask_available() for check of cpumask variable
This fixes the following clang warning when CONFIG_CPUMASK_OFFSTACK=n:

kernel/irq/manage.c:839:28: error: address of array
'desc->irq_common_data.affinity' will always evaluate to 'true'
[-Werror,-Wpointer-bool-conversion]

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Cc: Grant Grundler <grundler@chromium.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Greg Hackmann <ghackmann@google.com>
Cc: Michael Davidson <md@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20170412182030.83657-2-mka@chromium.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-14 20:49:27 +02:00
Peter Zijlstra 94ffac5d84 futex: Fix small (and harmless looking) inconsistencies
During (post-commit) review Darren spotted a few minor things. One
(harmless AFAICT) type inconsistency and a comment that wasn't as
clear as hoped.

Reported-by: Darren Hart (VMWare) <dvhart@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Darren Hart (VMware) <dvhart@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-14 10:30:07 +02:00
Thomas Gleixner 97181f9bd5 futex: Avoid freeing an active timer
Alexander reported a hrtimer debug_object splat:

  ODEBUG: free active (active state 0) object type: hrtimer hint: hrtimer_wakeup (kernel/time/hrtimer.c:1423)

  debug_object_free (lib/debugobjects.c:603)
  destroy_hrtimer_on_stack (kernel/time/hrtimer.c:427)
  futex_lock_pi (kernel/futex.c:2740)
  do_futex (kernel/futex.c:3399)
  SyS_futex (kernel/futex.c:3447 kernel/futex.c:3415)
  do_syscall_64 (arch/x86/entry/common.c:284)
  entry_SYSCALL64_slow_path (arch/x86/entry/entry_64.S:249)

Which was caused by commit:

  cfafcd117d ("futex: Rework futex_lock_pi() to use rt_mutex_*_proxy_lock()")

... losing the hrtimer_cancel() in the shuffle. Where previously the
hrtimer_cancel() was done by rt_mutex_slowlock() we now need to do it
manually.

Reported-by: Alexander Levin <alexander.levin@verizon.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: cfafcd117d ("futex: Rework futex_lock_pi() to use rt_mutex_*_proxy_lock()")
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1704101802370.2906@nanos
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-14 10:29:53 +02:00
Ingo Molnar 0ba78a95a6 Merge branch 'linus' into locking/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-14 10:29:40 +02:00
Peter Zijlstra 283e2ed399 sched/fair: Move the PELT constants into a generated header
Now that we have a tool to generate the PELT constants in C form,
use its output as a separate header.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-14 10:26:37 +02:00
Peter Zijlstra bb0bd044e6 sched/fair: Increase PELT accuracy for small tasks
We truncate (and loose) the lower 10 bits of runtime in
___update_load_avg(), this means there's a consistent bias to
under-account tasks. This is esp. significant for small tasks.

Cure this by only forwarding last_update_time to the point we've
actually accounted for, leaving the remainder for the next time.

Reported-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-14 10:26:36 +02:00
Peter Zijlstra 3841cdc310 sched/fair: Fix comments
Historically our periods (or p) argument in PELT denoted the number of
full periods (what is now d2). However recent patches have changed
this to the total decay (previously p+1), leading to a confusing
discrepancy between comments and code.

Try and clarify things by making periods (in code) and p (in comments)
be the same thing (again).

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-14 10:26:36 +02:00
Peter Zijlstra 05296e7535 sched/fair: Fix corner case in __accumulate_sum()
Paul noticed that in the (periods >= LOAD_AVG_MAX_N) case in
__accumulate_sum(), the returned contribution value (LOAD_AVG_MAX) is
incorrect.

This is because at this point, the decay_load() on the old state --
the first step in accumulate_sum() -- will not have resulted in 0, and
will therefore result in a sum larger than the maximum value of our
series. Obviously broken.

Note that:

	decay_load(LOAD_AVG_MAX, LOAD_AVG_MAX_N) =

                1   (345 / 32)
	47742 * - ^            = ~27
                2

Not to mention that any further contribution from the d3 segment (our
new period) would also push it over the maximum.

Solve this by noting that we can write our c2 term:

		    p
	c2 = 1024 \Sum y^n
		   n=1

In terms of our maximum value:

		    inf		      inf	  p
	max = 1024 \Sum y^n = 1024 ( \Sum y^n + \Sum y^n + y^0 )
		    n=0		      n=p+1	 n=1

Further note that:

           inf              inf            inf
        ( \Sum y^n ) y^p = \Sum y^(n+p) = \Sum y^n
           n=0              n=0            n=p

Combined that gives us:

		    p
	c2 = 1024 \Sum y^n
		   n=1

		     inf        inf
	   = 1024 ( \Sum y^n - \Sum y^n - y^0 )
		     n=0        n=p+1

	   = max - (max y^(p+1)) - 1024

Further simplify things by dealing with p=0 early on.

Reported-by: Paul Turner <pjt@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yuyang Du <yuyang.du@intel.com>
Cc: linux-kernel@vger.kernel.org
Fixes: a481db34b9 ("sched/fair: Optimize ___update_sched_avg()")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-14 10:26:34 +02:00
Keith Busch 3412386b53 irq/affinity: Fix extra vecs calculation
This fixes a math error calculating the extra_vecs. The error assumed
only 1 cpu per vector, but the value needs to account for the actual
number of cpus per vector in order to get the correct remainder for
extra CPU assignment.

Fixes: 7bf8222b9b ("irq/affinity: Fix CPU spread for unbalanced nodes")
Reported-by: Xiaolong Ye <xiaolong.ye@intel.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Link: http://lkml.kernel.org/r/1492104492-19943-1-git-send-email-keith.busch@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-13 23:41:00 +02:00
Johannes Berg 2d4bc93368 netlink: extended ACK reporting
Add the base infrastructure and UAPI for netlink extended ACK
reporting. All "manual" calls to netlink_ack() pass NULL for now and
thus don't get extended ACK reporting.

Big thanks goes to Pablo Neira Ayuso for not only bringing up the
whole topic at netconf (again) but also coming up with the nlattr
passing trick and various other ideas.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-13 13:58:20 -04:00
Rafael J. Wysocki 39b64aa1c0 cpufreq: schedutil: Reduce frequencies slower
The schedutil governor reduces frequencies too fast in some
situations which cases undesirable performance drops to
appear.

To address that issue, make schedutil reduce the frequency slower by
setting it to the average of the value chosen during the previous
iteration of governor computations and the new one coming from its
frequency selection formula.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=194963
Reported-by: John <john.ettedgui@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2017-04-13 03:46:40 +02:00
Aleksey Makarov cf39bf58af printk: fix double printing with earlycon
If a console was specified by ACPI SPCR table _and_ command line
parameters like "console=ttyAMA0" _and_ "earlycon" were specified,
then log messages appear twice.

The root cause is that the code traverses the list of specified
consoles (the `console_cmdline` array) and stops at the first match.
But it may happen that the same console is referred by the elements
of this array twice:

	pl011,mmio,0x87e024000000,115200 -- from SPCR
	ttyAMA0 -- from command line

but in this case `preferred_console` points to the second entry and
the flag CON_CONSDEV is not set, so bootconsole is not deregistered.

To fix that, introduce an invariant "The last non-braille console
is always the preferred one" on the entries of the console_cmdline
array.  Then traverse it in reverse order to be sure that if
the console is preferred then it will be the first matching entry.
Introduce variable console_cmdline_cnt that keeps the number
of elements of the console_cmdline array (Petr Mladek).  It helps
to get rid of the loop that searches for the end of this array.

Link: http://lkml.kernel.org/r/20170405202006.18234-1-aleksey.makarov@linaro.org
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: "Nair, Jayachandran" <Jayachandran.Nair@cavium.com>
Cc: linux-serial@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Aleksey Makarov <aleksey.makarov@linaro.org>
Reported-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2017-04-12 11:40:22 +02:00
Aleksey Makarov ad86ee2b8a printk: rename selected_console -> preferred_console
The variable selected_console is set in __add_preferred_console()
to point to the last console parameter that was added to the
console_cmdline array.

Rename it to preferred_console so that the name reflects the usage.

Petr Mladek:
"[..] the selected_console/preferred_console
value is used to keep the console first in the console_drivers list.
IMHO, the main effect is that each line will first appear on this
console, see call_console_drivers(). But the message will still
appear also on all other enabled consoles. From this point,
the name "preferred" sounds better to me. More consoles
are selected (enabled) and only one is preferred (first)."

Link: http://lkml.kernel.org/r/20170315102854.1763-3-aleksey.makarov@linaro.org
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: "Nair, Jayachandran" <Jayachandran.Nair@cavium.com>
Cc: linux-serial@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Aleksey Makarov <aleksey.makarov@linaro.org>
Suggested-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2017-04-12 11:40:19 +02:00
Aleksey Makarov b077bafa2f printk: fix name/type/scope of preferred_console var
The variable preferred_console is used only inside register_console()
and its semantics is boolean.  It is negative when no console has been
made preferred.

Make it static bool and rename to has_preferred.

Renaming was suggested by Peter Hurley

Link: http://lkml.kernel.org/r/20170315102854.1763-2-aleksey.makarov@linaro.org
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: "Nair, Jayachandran" <Jayachandran.Nair@cavium.com>
Cc: linux-serial@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Aleksey Makarov <aleksey.makarov@linaro.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2017-04-12 11:40:15 +02:00
Linus Torvalds b9b3322f13 Merge branch 'stable-4.11' of git://git.infradead.org/users/pcmoore/audit
Pull audit fix from Paul Moore:
 "One more small audit fix, this should be the last for v4.11.

  Seth Forshee noticed a problem where the audit retry queue wasn't
  being flushed properly when audit was enabled and the audit daemon
  wasn't running; this patches fixes the problem (see the commit
  description for more details on the change).

  Both Seth and I have tested this and everything looks good"

* 'stable-4.11' of git://git.infradead.org/users/pcmoore/audit:
  audit: make sure we don't let the retry queue grow without bounds
2017-04-12 00:02:33 -07:00
Linus Torvalds 06ea4c38bc Merge branch 'for-4.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:
 "This contains fixes for two long standing subtle bugs:

   - kthread_bind() on a new kthread binds it to specific CPUs and
     prevents userland from messing with the affinity or cgroup
     membership. Unfortunately, for cgroup membership, there's a window
     between kthread creation and kthread_bind*() invocation where the
     kthread can be moved into a non-root cgroup by userland.

     Depending on what controllers are in effect, this can assign the
     kthread unexpected attributes. For example, in the reported case,
     workqueue workers ended up in a non-root cpuset cgroups and had
     their CPU affinities overridden. This broke workqueue invariants
     and led to workqueue stalls.

     Fixed by closing the window between kthread creation and
     kthread_bind() as suggested by Oleg.

   - There was a bug in cgroup mount path which could allow two
     competing mount attempts to attach the same cgroup_root to two
     different superblocks.

     This was caused by mishandling return value from kernfs_pin_sb().

     Fixed"

* 'for-4.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: avoid attaching a cgroup root to two different superblocks
  cgroup, kthread: close race window where new kthreads can be migrated to non-root cgroups
2017-04-11 23:38:16 -07:00
Petr Mladek e679af627f livepatch: Cancel transition a safe way for immediate patches
klp_init_transition() does not set func->transition for immediate patches.
Then klp_ftrace_handler() could use the new code immediately. As a result,
it is not safe to put the livepatch module in klp_cancel_transition().

This patch reverts most of the last minute changes klp_cancel_transition().
It keeps the warning about a misuse because it still makes sense.

Fixes: 3ec24776bf ("livepatch: allow removal of a disabled patch")
Signed-off-by: Petr Mladek <pmladek@suse.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2017-04-11 20:54:27 +02:00
Willem de Bruijn 8f917bba00 bpf: pass sk to helper functions
BPF helper functions access socket fields through skb->sk. This is not
set in ingress cgroup and socket filters. The association is only made
in skb_set_owner_r once the filter has accepted the packet. Sk is
available as socket lookup has taken place.

Temporarily set skb->sk to sk in these cases.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-11 14:54:19 -04:00
Johannes Berg 40077e0cf6 bpf: remove struct bpf_map_type_list
There's no need to have struct bpf_map_type_list since
it just contains a list_head, the type, and the ops
pointer. Since the types are densely packed and not
actually dynamically registered, it's much easier and
smaller to have an array of type->ops pointer. Also
initialize this array statically to remove code needed
to initialize it.

In order to save duplicating the list, move it to the
types header file added by the previous patch and
include it in the same fashion.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-11 14:38:43 -04:00
Johannes Berg be9370a7d8 bpf: remove struct bpf_prog_type_list
There's no need to have struct bpf_prog_type_list since
it just contains a list_head, the type, and the ops
pointer. Since the types are densely packed and not
actually dynamically registered, it's much easier and
smaller to have an array of type->ops pointer. Also
initialize this array statically to remove code needed
to initialize it.

In order to save duplicating the list, move it to a new
header file and include it in the places needing it.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-11 14:38:43 -04:00
Johannes Berg 96a94cc515 bpf: reference may_access_skb() from __bpf_prog_run()
It took me quite some time to figure out how this was linked,
so in order to save the next person the effort of finding it
add a comment in __bpf_prog_run() that indicates what exactly
determines that a program can access the ctx == skb.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-11 10:54:27 -04:00
NeilBrown 717a94b5fc sched/core: Remove 'task' parameter and rename tsk_restore_flags() to current_restore_flags()
It is not safe for one thread to modify the ->flags
of another thread as there is no locking that can protect
the update.

So tsk_restore_flags(), which takes a task pointer and modifies
the flags, is an invitation to do the wrong thing.

All current users pass "current" as the task, so no developers have
accepted that invitation.  It would be best to ensure it remains
that way.

So rename tsk_restore_flags() to current_restore_flags() and don't
pass in a task_struct pointer.  Always operate on current->flags.

Signed-off-by: NeilBrown <neilb@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-11 09:06:32 +02:00
Ingo Molnar 36a4dfc378 Linux 4.11-rc6
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Merge tag 'v4.11-rc6' into sched/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-11 09:05:36 +02:00
Ingo Molnar 84b1e36a6a Linux 4.11-rc6
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Merge tag 'v4.11-rc6' into perf/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-11 08:42:47 +02:00
Zefan Li bfb0b80db5 cgroup: avoid attaching a cgroup root to two different superblocks
Run this:

    touch file0
    for ((; ;))
    {
        mount -t cpuset xxx file0
    }

And this concurrently:

    touch file1
    for ((; ;))
    {
        mount -t cpuset xxx file1
    }

We'll trigger a warning like this:

 ------------[ cut here ]------------
 WARNING: CPU: 1 PID: 4675 at lib/percpu-refcount.c:317 percpu_ref_kill_and_confirm+0x92/0xb0
 percpu_ref_kill_and_confirm called more than once on css_release!
 CPU: 1 PID: 4675 Comm: mount Not tainted 4.11.0-rc5+ #5
 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
 Call Trace:
  dump_stack+0x63/0x84
  __warn+0xd1/0xf0
  warn_slowpath_fmt+0x5f/0x80
  percpu_ref_kill_and_confirm+0x92/0xb0
  cgroup_kill_sb+0x95/0xb0
  deactivate_locked_super+0x43/0x70
  deactivate_super+0x46/0x60
 ...
 ---[ end trace a79f61c2a2633700 ]---

Here's a race:

  Thread A				Thread B

  cgroup1_mount()
    # alloc a new cgroup root
    cgroup_setup_root()
					cgroup1_mount()
					  # no sb yet, returns NULL
					  kernfs_pin_sb()

					  # but succeeds in getting the refcnt,
					  # so re-use cgroup root
					  percpu_ref_tryget_live()
    # alloc sb with cgroup root
    cgroup_do_mount()

  cgroup_kill_sb()
					  # alloc another sb with same root
					  cgroup_do_mount()

					cgroup_kill_sb()

We end up using the same cgroup root for two different superblocks,
so percpu_ref_kill() will be called twice on the same root when the
two superblocks are destroyed.

We should fix to make sure the superblock pinning is really successful.

Cc: stable@vger.kernel.org # 3.16+
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-04-11 09:00:57 +09:00
Rakib Mullick 30e03acda5 cpuset: Remove cpuset_update_active_cpus()'s parameter.
In cpuset_update_active_cpus(), cpu_online isn't used anymore. Remove
it.

Signed-off-by: Rakib Mullick<rakib.mullick@gmail.com>
Acked-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-04-11 08:57:54 +09:00
Dave Airlie b769fefb68 Linux 4.11-rc6
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Backmerge tag 'v4.11-rc6' into drm-next

Linux 4.11-rc6

drm-misc needs 4.11-rc5, may as well fix conflicts with rc6.
2017-04-11 07:40:42 +10:00
Steven Rostedt (VMware) 03ecd3f48e rcu/tracing: Add rcu_disabled to denote when rcu_irq_enter() will not work
Tracing uses rcu_irq_enter() as a way to make sure that RCU is watching when
it needs to use rcu_read_lock() and friends. This is because tracing can
happen as RCU is about to enter user space, or about to go idle, and RCU
does not watch for RCU read side critical sections as it makes the
transition.

There is a small location within the RCU infrastructure that rcu_irq_enter()
itself will not work. If tracing were to occur in that section it will break
if it tries to use rcu_irq_enter().

Originally, this happens with the stack_tracer, because it will call
save_stack_trace when it encounters stack usage that is greater than any
stack usage it had encountered previously. There was a case where that
happened in the RCU section where rcu_irq_enter() did not work, and lockdep
complained loudly about it. To fix it, stack tracing added a call to be
disabled and RCU would disable stack tracing during the critical section
that rcu_irq_enter() was inoperable. This solution worked, but there are
other cases that use rcu_irq_enter() and it would be a good idea to let RCU
give a way to let others know that rcu_irq_enter() will not work. For
example, in trace events.

Another helpful aspect of this change is that it also moves the per cpu
variable called in the RCU critical section into a cache locale along with
other RCU per cpu variables used in that same location.

I'm keeping the stack_trace_disable() code, as that still could be used in
the future by places that really need to disable it. And since it's only a
static inline, it wont take up any kernel text if it is not used.

Link: http://lkml.kernel.org/r/20170405093207.404f8deb@gandalf.local.home

Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-10 15:22:03 -04:00
Paul E. McKenney a278d47189 rcu: Fix dyntick-idle tracing
The tracing subsystem started using rcu_irq_entry() and rcu_irq_exit()
(with my blessing) to allow the current _rcuidle alternative tracepoint
name to be dispensed with while still maintaining good performance.
Unfortunately, this causes RCU's dyntick-idle entry code's tracing to
appear to RCU like an interrupt that occurs where RCU is not designed
to handle interrupts.

This commit fixes this problem by moving the zeroing of ->dynticks_nesting
after the offending trace_rcu_dyntick() statement, which narrows the
window of vulnerability to a pair of adjacent statements that are now
marked with comments to that effect.

Link: http://lkml.kernel.org/r/20170405093207.404f8deb@gandalf.local.home
Link: http://lkml.kernel.org/r/20170405193928.GM1600@linux.vnet.ibm.com

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-10 15:21:57 -04:00
Steven Rostedt (VMware) 8aaf1ee70e tracing: Rename trace_active to disable_stack_tracer and inline its modification
In order to eliminate a function call, make "trace_active" into
"disable_stack_tracer" and convert stack_tracer_disable() and friends into
static inline functions.

Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-10 15:21:47 -04:00
Steven Rostedt (VMware) 5367278cb7 tracing: Add stack_tracer_disable/enable() functions
There are certain parts of the kernel that cannot let stack tracing
proceed (namely in RCU), because the stack tracer uses RCU, and parts of RCU
internals cannot handle having RCU read side locks taken.

Add stack_tracer_disable() and stack_tracer_enable() functions to let RCU
stop stack tracing on the current CPU when it is in those critical sections.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-10 14:34:10 -04:00
Steven Rostedt (VMware) 252babcd52 tracing: Replace the per_cpu() with __this_cpu*() in trace_stack.c
The updates to the trace_active per cpu variable can be updated with the
__this_cpu_*() functions as it only gets updated on the CPU that the variable
is on.

Thanks to Paul McKenney for suggesting __this_cpu_* instead of this_cpu_*.

Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-10 14:33:54 -04:00
Jan Kara 054c636e5c fsnotify: Move ->free_mark callback to fsnotify_ops
Pointer to ->free_mark callback unnecessarily occupies one long in each
fsnotify_mark although they are the same for all marks from one
notification group. Move the callback pointer to fsnotify_ops.

Reviewed-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-10 17:37:36 +02:00
Jan Kara 7b12932340 fsnotify: Add group pointer in fsnotify_init_mark()
Currently we initialize mark->group only in fsnotify_add_mark_lock().
However we will need to access fsnotify_ops of corresponding group from
fsnotify_put_mark() so we need mark->group initialized earlier. Do that
in fsnotify_init_mark() which has a consequence that once
fsnotify_init_mark() is called on a mark, the mark has to be destroyed
by fsnotify_put_mark().

Reviewed-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-10 17:37:36 +02:00
Jan Kara b1362edfe1 fsnotify: Remove fsnotify_find_{inode|vfsmount}_mark()
These are very thin wrappers, just remove them. Drop
fs/notify/vfsmount_mark.c as it is empty now.

Reviewed-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-10 17:37:36 +02:00
Jan Kara 9385a84d7e fsnotify: Pass fsnotify_iter_info into handle_event handler
Pass fsnotify_iter_info into ->handle_event() handler so that it can
release and reacquire SRCU lock via fsnotify_prepare_user_wait() and
fsnotify_finish_user_wait() functions.  These functions also make sure
current marks are appropriately pinned so that iteration protected by
srcu in fsnotify() stays safe.

Reviewed-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-10 17:37:36 +02:00
Jan Kara 6b3f05d24d fsnotify: Detach mark from object list when last reference is dropped
Instead of removing mark from object list from fsnotify_detach_mark(),
remove the mark when last reference to the mark is dropped. This will
allow fanotify to wait for userspace response to event without having to
hold onto fsnotify_mark_srcu.

To avoid pinning inodes by elevated refcount (and thus e.g. delaying
file deletion) while someone holds mark reference, we detach connector
from the object also from fsnotify_destroy_marks() and not only after
removing last mark from the list as it was now.

Reviewed-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-10 17:37:36 +02:00
Jan Kara 08991e83b7 fsnotify: Free fsnotify_mark_connector when there is no mark attached
Currently we free fsnotify_mark_connector structure only when inode /
vfsmount is getting freed. This can however impose noticeable memory
overhead when marks get attached to inodes only temporarily. So free the
connector structure once the last mark is detached from the object.
Since notification infrastructure can be working with the connector
under the protection of fsnotify_mark_srcu, we have to be careful and
free the fsnotify_mark_connector only after SRCU period passes.

Reviewed-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-10 17:37:35 +02:00
Jan Kara 86ffe245c4 fsnotify: Move object pointer to fsnotify_mark_connector
Move pointer to inode / vfsmount from mark itself to the
fsnotify_mark_connector structure. This is another step on the path
towards decoupling inode / vfsmount lifetime from notification mark
lifetime.

Reviewed-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-10 17:37:35 +02:00
Jan Kara 9dd813c15b fsnotify: Move mark list head from object into dedicated structure
Currently notification marks are attached to object (inode or vfsmnt) by
a hlist_head in the object. The list is also protected by a spinlock in
the object. So while there is any mark attached to the list of marks,
the object must be pinned in memory (and thus e.g. last iput() deleting
inode cannot happen). Also for list iteration in fsnotify() to work, we
must hold fsnotify_mark_srcu lock so that mark itself and
mark->obj_list.next cannot get freed. Thus we are required to wait for
response to fanotify events from userspace process with
fsnotify_mark_srcu lock held. That causes issues when userspace process
is buggy and does not reply to some event - basically the whole
notification subsystem gets eventually stuck.

So to be able to drop fsnotify_mark_srcu lock while waiting for
response, we have to pin the mark in memory and make sure it stays in
the object list (as removing the mark waiting for response could lead to
lost notification events for groups later in the list). However we don't
want inode reclaim to block on such mark as that would lead to system
just locking up elsewhere.

This commit is the first in the series that paves way towards solving
these conflicting lifetime needs. Instead of anchoring the list of marks
directly in the object, we anchor it in a dedicated structure
(fsnotify_mark_connector) and just point to that structure from the
object. The following commits will also add spinlock protecting the list
and object pointer to the structure.

Reviewed-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-10 17:37:34 +02:00
Jan Kara 43471d15df audit_tree: Use mark flags to check whether mark is alive
Currently audit code uses checking of mark->inode to verify whether mark
is still alive. Switch that to checking mark flags as that is more
logical and current way will become unreliable in future.

Reviewed-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-10 17:36:32 +02:00
Paul Moore 264d509637 audit: make sure we don't let the retry queue grow without bounds
The retry queue is intended to provide a temporary buffer in the case
of transient errors when communicating with auditd, it is not meant
as a long life queue, that functionality is provided by the hold
queue.

This patch fixes a problem identified by Seth where the retry queue
could grow uncontrollably if an auditd instance did not connect to
the kernel to drain the queues.  This commit fixes this by doing the
following:

* Make sure we always call auditd_reset() if we decide the connection
with audit is really dead.  There were some cases in
kauditd_hold_skb() where we did not reset the connection, this patch
relocates the reset calls to kauditd_thread() so all the error
conditions are caught and the connection reset.  As a side effect,
this means we could move auditd_reset() and get rid of the forward
definition at the top of kernel/audit.c.

* We never checked the status of the auditd connection when
processing the main audit queue which meant that the retry queue
could grow unchecked.  This patch adds a call to auditd_reset()
after the main queue has been processed if auditd is not connected,
the auditd_reset() call will make sure the retry and hold queues are
correctly managed/flushed so that the retry queue remains reasonable.

Cc: <stable@vger.kernel.org> # 4.10.x-: 5b52330bbf
Reported-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-04-10 11:16:59 -04:00
Jason A. Donenfeld 07a77929ba padata: free correct variable
The author meant to free the variable that was just allocated, instead
of the one that failed to be allocated, but made a simple typo. This
patch rectifies that.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-04-10 19:17:27 +08:00
Liping Zhang 425fffd886 sysctl: report EINVAL if value is larger than UINT_MAX for proc_douintvec
Currently, inputting the following command will succeed but actually the
value will be truncated:

  # echo 0x12ffffffff > /proc/sys/net/ipv4/tcp_notsent_lowat

This is not friendly to the user, so instead, we should report error
when the value is larger than UINT_MAX.

Fixes: e7d316a02f ("sysctl: handle error writing UINT_MAX to u32 fields")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Cc: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-08 10:27:40 -07:00
Linus Torvalds 62fedca5ce Merge branch 'stable-4.11' of git://git.infradead.org/users/pcmoore/audit
Pull audit cleanup from Paul Moore:
 "A week later than I had hoped, but as promised, here is the audit
  uninline-fix we talked about during the last audit pull request.

  The patch is slightly different than what we originally discussed as
  it made more sense to keep the audit_signal_info() function in
  auditsc.c rather than move it and bunch of other related
  variables/definitions into audit.c/audit.h.

  At some point in the future I need to look at how the audit code is
  organized across kernel/audit*, I suspect we could do things a bit
  better, but it doesn't seem like a -rc release is a good place for
  that ;)

  Regardless, this patch passes our tests without problem and looks good
  for v4.11"

* 'stable-4.11' of git://git.infradead.org/users/pcmoore/audit:
  audit: move audit_signal_info() into kernel/auditsc.c
2017-04-08 01:37:25 -07:00
bsegall@google.com 5402e97af6 ptrace: fix PTRACE_LISTEN race corrupting task->state
In PT_SEIZED + LISTEN mode STOP/CONT signals cause a wakeup against
__TASK_TRACED.  If this races with the ptrace_unfreeze_traced at the end
of a PTRACE_LISTEN, this can wake the task /after/ the check against
__TASK_TRACED, but before the reset of state to TASK_TRACED.  This
causes it to instead clobber TASK_WAKING, allowing a subsequent wakeup
against TRACED while the task is still on the rq wake_list, corrupting
it.

Oleg said:
 "The kernel can crash or this can lead to other hard-to-debug problems.
  In short, "task->state = TASK_TRACED" in ptrace_unfreeze_traced()
  assumes that nobody else can wake it up, but PTRACE_LISTEN breaks the
  contract. Obviusly it is very wrong to manipulate task->state if this
  task is already running, or WAKING, or it sleeps again"

[akpm@linux-foundation.org: coding-style fixes]
Fixes: 9899d11f ("ptrace: ensure arch_ptrace/ptrace_request can never race with SIGKILL")
Link: http://lkml.kernel.org/r/xm26y3vfhmkp.fsf_-_@bsegall-linux.mtv.corp.google.com
Signed-off-by: Ben Segall <bsegall@google.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-08 00:47:48 -07:00
Liping Zhang 5380e5644a sysctl: don't print negative flag for proc_douintvec
I saw some very confusing sysctl output on my system:
  # cat /proc/sys/net/core/xfrm_aevent_rseqth
  -2
  # cat /proc/sys/net/core/xfrm_aevent_etime
  -10
  # cat /proc/sys/net/ipv4/tcp_notsent_lowat
  -4294967295

Because we forget to set the *negp flag in proc_douintvec, so it will
become a garbage value.

Since the value related to proc_douintvec is always an unsigned integer,
so we can set *negp to false explictily to fix this issue.

Fixes: e7d316a02f ("sysctl: handle error writing UINT_MAX to u32 fields")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Cc: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-07 09:46:44 -07:00
Steven Rostedt (VMware) 0598e4f08e ftrace: Add use of synchronize_rcu_tasks() with dynamic trampolines
The function tracer needs to be more careful than other subsystems when it
comes to freeing data. Especially if that data is actually executable code.
When a single function is traced, a trampoline can be dynamically allocated
which is called to jump to the function trace callback. When the callback is
no longer needed, the dynamic allocated trampoline needs to be freed. This
is where the issues arise. The dynamically allocated trampoline must not be
used again. As function tracing can trace all subsystems, including
subsystems that are used to serialize aspects of freeing (namely RCU), it
must take extra care when doing the freeing.

Before synchronize_rcu_tasks() was around, there was no way for the function
tracer to know that nothing was using the dynamically allocated trampoline
when CONFIG_PREEMPT was enabled. That's because a task could be indefinitely
preempted while sitting on the trampoline. Now with synchronize_rcu_tasks(),
it will wait till all tasks have either voluntarily scheduled (not on the
trampoline) or goes into userspace (not on the trampoline). Then it is safe
to free the trampoline even with CONFIG_PREEMPT set.

Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-07 09:41:51 -04:00
Linus Torvalds 4691f4a6d4 Wei Yongjun fixed a long standing bug in the ring buffer startup test.
If for some unknown reason, the kthread that is created fails to be
 created, the return from kthread_create() is an PTR_ERR and not a NULL.
 The test incorrectly checks for NULL instead of an error.
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Merge tag 'trace-v4.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "Wei Yongjun fixed a long standing bug in the ring buffer startup test.

  If for some unknown reason, the kthread that is created fails to be
  created, the return from kthread_create() is an PTR_ERR and not a
  NULL. The test incorrectly checks for NULL instead of an error"

* tag 'trace-v4.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ring-buffer: Fix return value check in test_ringbuffer()
2017-04-06 13:12:12 -07:00
David S. Miller 6f14f443d3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Mostly simple cases of overlapping changes (adding code nearby,
a function whose name changes, for example).

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-06 08:24:51 -07:00
Linus Torvalds ea6b1720ce Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Reject invalid updates to netfilter expectation policies, from Pablo
    Neira Ayuso.

 2) Fix memory leak in nfnl_cthelper, from Jeffy Chen.

 3) Don't do stupid things if we get a neigh_probe() on a neigh entry
    whose ops lack a solicit method. From Eric Dumazet.

 4) Don't transmit packets in r8152 driver when the carrier is off, from
    Hayes Wang.

 5) Fix ipv6 packet type detection in aquantia driver, from Pavel
    Belous.

 6) Don't write uninitialized data into hw registers in bna driver, from
    Arnd Bergmann.

 7) Fix locking in ping_unhash(), from Eric Dumazet.

 8) Make BPF verifier range checks able to understand certain sequences
    emitted by LLVM, from Alexei Starovoitov.

 9) Fix use after free in ipconfig, from Mark Rutland.

10) Fix refcount leak on force commit in openvswitch, from Jarno
    Rajahalme.

11) Fix various overflow checks in AF_PACKET, from Andrey Konovalov.

12) Fix endianness bug in be2net driver, from Suresh Reddy.

13) Don't forget to wake TX queues when processing a timeout, from
    Grygorii Strashko.

14) ARP header on-stack storage is wrong in flow dissector, from Simon
    Horman.

15) Lost retransmit and reordering SNMP stats in TCP can be
    underreported. From Yuchung Cheng.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (82 commits)
  nfp: fix potential use after free on xdp prog
  tcp: fix reordering SNMP under-counting
  tcp: fix lost retransmit SNMP under-counting
  sctp: get sock from transport in sctp_transport_update_pmtu
  net: ethernet: ti: cpsw: fix race condition during open()
  l2tp: fix PPP pseudo-wire auto-loading
  bnx2x: fix spelling mistake in macros HW_INTERRUT_ASSERT_SET_*
  l2tp: take reference on sessions being dumped
  tcp: minimize false-positives on TCP/GRO check
  sctp: check for dst and pathmtu update in sctp_packet_config
  flow dissector: correct size of storage for ARP
  net: ethernet: ti: cpsw: wake tx queues on ndo_tx_timeout
  l2tp: take a reference on sessions used in genetlink handlers
  l2tp: hold session while sending creation notifications
  l2tp: fix duplicate session creation
  l2tp: ensure session can't get removed during pppol2tp_session_ioctl()
  l2tp: fix race in l2tp_recv_common()
  sctp: use right in and out stream cnt
  bpf: add various verifier test cases for self-tests
  bpf, verifier: fix rejection of unaligned access checks for map_value_adj
  ...
2017-04-05 20:17:38 -07:00
Mike Galbraith def34eaae5 rtmutex: Plug preempt count leak in rt_mutex_futex_unlock()
mark_wakeup_next_waiter() already disables preemption, doing so again
leaves us with an unpaired preempt_disable().

Fixes: 2a1c602994 ("rtmutex: Deboost before waking up the top waiter")
Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: xlpang@redhat.com
Cc: rostedt@goodmis.org
Link: http://lkml.kernel.org/r/1491379707.6538.2.camel@gmx.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-05 16:59:37 +02:00
Herbert Xu c6dc060906 Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Merge the crypto tree to resolve conflict between caam changes.
2017-04-05 21:57:07 +08:00
Wei Yongjun 62277de758 ring-buffer: Fix return value check in test_ringbuffer()
In case of error, the function kthread_run() returns ERR_PTR()
and never returns NULL. The NULL test in the return value check
should be replaced with IS_ERR().

Link: http://lkml.kernel.org/r/1466184839-14927-1-git-send-email-weiyj_lk@163.com

Cc: stable@vger.kernel.org
Fixes: 6c43e554a ("ring-buffer: Add ring buffer startup selftest")
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-05 09:36:52 -04:00
Jan Kara f410ff6554 audit: Abstract hash key handling
Audit tree currently uses inode pointer as a key into the hash table.
Getting that from notification mark will be somewhat more difficult with
coming fsnotify changes. So abstract getting of hash key from the audit
chunk and inode so that we can change the method to obtain a key easily.

Reviewed-by: Miklos Szeredi <mszeredi@redhat.com>
CC: Paul Moore <paul@paul-moore.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-05 09:39:37 +02:00
Alban Crequy 696ced4fb1 tracing/kprobes: expose maxactive for kretprobe in kprobe_events
When a kretprobe is installed on a kernel function, there is a maximum
limit of how many calls in parallel it can catch (aka "maxactive"). A
kernel module could call register_kretprobe() and initialize maxactive
(see example in samples/kprobes/kretprobe_example.c).

But that is not exposed to userspace and it is currently not possible to
choose maxactive when writing to /sys/kernel/debug/tracing/kprobe_events

The default maxactive can be as low as 1 on single-core with a
non-preemptive kernel. This is too low and we need to increase it not
only for recursive functions, but for functions that sleep or resched.

This patch updates the format of the command that can be written to
kprobe_events so that maxactive can be optionally specified.

I need this for a bpf program attached to the kretprobe of
inet_csk_accept, which can sleep for a long time.

This patch includes a basic selftest:

> # ./ftracetest -v  test.d/kprobe/
> === Ftrace unit tests ===
> [1] Kprobe dynamic event - adding and removing	[PASS]
> [2] Kprobe dynamic event - busy event check	[PASS]
> [3] Kprobe dynamic event with arguments	[PASS]
> [4] Kprobes event arguments with types	[PASS]
> [5] Kprobe dynamic event with function tracer	[PASS]
> [6] Kretprobe dynamic event with arguments	[PASS]
> [7] Kretprobe dynamic event with maxactive	[PASS]
>
> # of passed:  7
> # of failed:  0
> # of unresolved:  0
> # of untested:  0
> # of unsupported:  0
> # of xfailed:  0
> # of undefined(test bug):  0

BugLink: https://github.com/iovisor/bcc/issues/1072
Link: http://lkml.kernel.org/r/1491215782-15490-1-git-send-email-alban@kinvolk.io

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Alban Crequy <alban@kinvolk.io>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-04 10:32:03 -04:00
Petr Mladek 257ab44311 printk: Correctly handle preemption in console_unlock()
Some console drivers code calls console_conditional_schedule()
that looks at @console_may_schedule. The value must be cleared
when the drivers are called from console_unlock() with
interrupts disabled. But rescheduling is fine when the same
code is called, for example, from tty operations where the
console semaphore is taken via console_lock().

This is why @console_may_schedule is cleared before calling console
drivers. The original value is stored to decide if we could sleep
between lines.

Now, @console_may_schedule is not cleared when we call
console_trylock() and jump back to the "again" goto label.
This has become a problem, since the commit 6b97a20d3a
("printk: set may_schedule for some of console_trylock() callers").
@console_may_schedule might get enabled now.

There is also the opposite problem. console_lock() can be called
only from preemptive context. It can always enable scheduling in
the console code. But console_trylock() is not able to detect it
when CONFIG_PREEMPT_COUNT is disabled. Therefore we should use the
original @console_may_schedule value after re-acquiring
the console semaphore in console_unlock().

This patch solves both problems by moving the "again" goto label.

Alternative solution was to clear and restore the value around
call_console_drivers(). Then console_conditional_schedule() could
be used also inside console_unlock(). But there was a potential race
with console_flush_on_panic() as reported by Sergey Senozhatsky.
That function should be called only where there is only one CPU
and with interrupts disabled. But better be on the safe side
because stopping CPUs might fail.

Fixes: 6b97a20d3a ("printk: set may_schedule for some of console_trylock() callers")
Link: http://lkml.kernel.org/r/1490372045-22288-1-git-send-email-pmladek@suse.com
Suggested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-fbdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2017-04-04 14:08:01 +02:00
Keith Busch 7bf8222b9b irq/affinity: Fix CPU spread for unbalanced nodes
The irq_create_affinity_masks routine is responsible for assigning a
number of interrupt vectors to CPUs. The optimal assignemnet will spread
requested vectors to all CPUs, with the fewest CPUs sharing a vector.

The algorithm may fail to assign some vectors to any CPUs if a node's
CPU count is lower than the average number of vectors per node. These
vectors are unusable and create an un-optimal spread.

Recalculate the number of vectors to assign at each node iteration by using
the remaining number of vectors and nodes to be assigned, not exceeding the
number of CPUs in that node. This will guarantee that every CPU is assigned
at least one vector.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: linux-nvme@lists.infradead.org
Link: http://lkml.kernel.org/r/1491247553-7603-1-git-send-email-keith.busch@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-04 11:57:28 +02:00
Peter Zijlstra 19830e5524 rtmutex: Fix more prio comparisons
There was a pure ->prio comparison left in try_to_wake_rt_mutex(),
convert it to use rt_mutex_waiter_less(), noting that greater-or-equal
is not-less (both in kernel priority view).

This necessitated the introduction of cmp_task() which creates a
pointer to an unnamed stack variable of struct rt_mutex_waiter type to
compare against tasks.

With this, we can now also create and employ rt_mutex_waiter_equal().

Reviewed-and-tested-by: Juri Lelli <juri.lelli@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: juri.lelli@arm.com
Cc: bigeasy@linutronix.de
Cc: xlpang@redhat.com
Cc: rostedt@goodmis.org
Cc: mathieu.desnoyers@efficios.com
Cc: jdesfossez@efficios.com
Cc: bristot@redhat.com
Link: http://lkml.kernel.org/r/20170323150216.455584638@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-04 11:44:07 +02:00
Peter Zijlstra e0aad5b44f rtmutex: Fix PI chain order integrity
rt_mutex_waiter::prio is a copy of task_struct::prio which is updated
during the PI chain walk, such that the PI chain order isn't messed up
by (asynchronous) task state updates.

Currently rt_mutex_waiter_less() uses task state for deadline tasks;
this is broken, since the task state can, as said above, change
asynchronously, causing the RB tree order to change without actual
tree update -> FAIL.

Fix this by also copying the deadline into the rt_mutex_waiter state
and updating it along with its prio field.

Ideally we would also force PI chain updates whenever DL tasks update
their deadline parameter, but for first approximation this is less
broken than it was.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: juri.lelli@arm.com
Cc: bigeasy@linutronix.de
Cc: xlpang@redhat.com
Cc: rostedt@goodmis.org
Cc: mathieu.desnoyers@efficios.com
Cc: jdesfossez@efficios.com
Cc: bristot@redhat.com
Link: http://lkml.kernel.org/r/20170323150216.403992539@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-04 11:44:06 +02:00
Peter Zijlstra b91473ff6e sched,tracing: Update trace_sched_pi_setprio()
Pass the PI donor task, instead of a numerical priority.

Numerical priorities are not sufficient to describe state ever since
SCHED_DEADLINE.

Annotate all sched tracepoints that are currently broken; fixing them
will bork userspace. *hate*.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: juri.lelli@arm.com
Cc: bigeasy@linutronix.de
Cc: xlpang@redhat.com
Cc: mathieu.desnoyers@efficios.com
Cc: jdesfossez@efficios.com
Cc: bristot@redhat.com
Link: http://lkml.kernel.org/r/20170323150216.353599881@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-04 11:44:06 +02:00
Peter Zijlstra acd58620e4 sched/rtmutex: Refactor rt_mutex_setprio()
With the introduction of SCHED_DEADLINE the whole notion that priority
is a single number is gone, therefore the @prio argument to
rt_mutex_setprio() doesn't make sense anymore.

So rework the code to pass a pi_task instead.

Note this also fixes a problem with pi_top_task caching; previously we
would not set the pointer (call rt_mutex_update_top_task) if the
priority didn't change, this could lead to a stale pointer.

As for the XXX, I think its fine to use pi_task->prio, because if it
differs from waiter->prio, a PI chain update is immenent.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: juri.lelli@arm.com
Cc: bigeasy@linutronix.de
Cc: xlpang@redhat.com
Cc: rostedt@goodmis.org
Cc: mathieu.desnoyers@efficios.com
Cc: jdesfossez@efficios.com
Cc: bristot@redhat.com
Link: http://lkml.kernel.org/r/20170323150216.303827095@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-04 11:44:06 +02:00
Peter Zijlstra aa2bfe5536 rtmutex: Clean up
Previous patches changed the meaning of the return value of
rt_mutex_slowunlock(); update comments and code to reflect this.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: juri.lelli@arm.com
Cc: bigeasy@linutronix.de
Cc: xlpang@redhat.com
Cc: rostedt@goodmis.org
Cc: mathieu.desnoyers@efficios.com
Cc: jdesfossez@efficios.com
Cc: bristot@redhat.com
Link: http://lkml.kernel.org/r/20170323150216.255058238@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-04 11:44:05 +02:00
Xunlei Pang 85e2d4f992 sched/deadline/rtmutex: Dont miss the dl_runtime/dl_period update
Currently dl tasks will actually return at the very beginning
of rt_mutex_adjust_prio_chain() in !detect_deadlock cases:

    if (waiter->prio == task->prio) {
        if (!detect_deadlock)
            goto out_unlock_pi; // out here
        else
            requeue = false;
    }

As the deadline value of blocked deadline tasks(waiters) without
changing their sched_class(thus prio doesn't change) never changes,
this seems reasonable, but it actually misses the chance of updating
rt_mutex_waiter's "dl_runtime(period)_copy" if a waiter updates its
deadline parameters(dl_runtime, dl_period) or boosted waiter changes
to !deadline class.

Thus, force deadline task not out by adding the !dl_prio() condition.

Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: juri.lelli@arm.com
Cc: bigeasy@linutronix.de
Cc: mathieu.desnoyers@efficios.com
Cc: jdesfossez@efficios.com
Cc: bristot@redhat.com
Link: http://lkml.kernel.org/r/1460633827-345-7-git-send-email-xlpang@redhat.com
Link: http://lkml.kernel.org/r/20170323150216.206577901@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-04 11:44:05 +02:00
Xunlei Pang e96a7705e7 sched/rtmutex/deadline: Fix a PI crash for deadline tasks
A crash happened while I was playing with deadline PI rtmutex.

    BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
    IP: [<ffffffff810eeb8f>] rt_mutex_get_top_task+0x1f/0x30
    PGD 232a75067 PUD 230947067 PMD 0
    Oops: 0000 [#1] SMP
    CPU: 1 PID: 10994 Comm: a.out Not tainted

    Call Trace:
    [<ffffffff810b658c>] enqueue_task+0x2c/0x80
    [<ffffffff810ba763>] activate_task+0x23/0x30
    [<ffffffff810d0ab5>] pull_dl_task+0x1d5/0x260
    [<ffffffff810d0be6>] pre_schedule_dl+0x16/0x20
    [<ffffffff8164e783>] __schedule+0xd3/0x900
    [<ffffffff8164efd9>] schedule+0x29/0x70
    [<ffffffff8165035b>] __rt_mutex_slowlock+0x4b/0xc0
    [<ffffffff81650501>] rt_mutex_slowlock+0xd1/0x190
    [<ffffffff810eeb33>] rt_mutex_timed_lock+0x53/0x60
    [<ffffffff810ecbfc>] futex_lock_pi.isra.18+0x28c/0x390
    [<ffffffff810ed8b0>] do_futex+0x190/0x5b0
    [<ffffffff810edd50>] SyS_futex+0x80/0x180

This is because rt_mutex_enqueue_pi() and rt_mutex_dequeue_pi()
are only protected by pi_lock when operating pi waiters, while
rt_mutex_get_top_task(), will access them with rq lock held but
not holding pi_lock.

In order to tackle it, we introduce new "pi_top_task" pointer
cached in task_struct, and add new rt_mutex_update_top_task()
to update its value, it can be called by rt_mutex_setprio()
which held both owner's pi_lock and rq lock. Thus "pi_top_task"
can be safely accessed by enqueue_task_dl() under rq lock.

Originally-From: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: juri.lelli@arm.com
Cc: bigeasy@linutronix.de
Cc: mathieu.desnoyers@efficios.com
Cc: jdesfossez@efficios.com
Cc: bristot@redhat.com
Link: http://lkml.kernel.org/r/20170323150216.157682758@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-04 11:44:05 +02:00
Xunlei Pang 2a1c602994 rtmutex: Deboost before waking up the top waiter
We should deboost before waking the high-priority task, such that we
don't run two tasks with the same "state" (priority, deadline,
sched_class, etc).

In order to make sure the boosting task doesn't start running between
unlock and deboost (due to 'spurious' wakeup), we move the deboost
under the wait_lock, that way its serialized against the wait loop in
__rt_mutex_slowlock().

Doing the deboost early can however lead to priority-inversion if
current would get preempted after the deboost but before waking our
high-prio task, hence we disable preemption before doing deboost, and
enabling it after the wake up is over.

This gets us the right semantic order, but most importantly however;
this change ensures pointer stability for the next patch, where we
have rt_mutex_setprio() cache a pointer to the top-most waiter task.
If we, as before this change, do the wakeup first and then deboost,
this pointer might point into thin air.

[peterz: Changelog + patch munging]
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: juri.lelli@arm.com
Cc: bigeasy@linutronix.de
Cc: mathieu.desnoyers@efficios.com
Cc: jdesfossez@efficios.com
Cc: bristot@redhat.com
Link: http://lkml.kernel.org/r/20170323150216.110065320@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-04 11:44:05 +02:00
Thomas Gleixner 38bffdac07 Merge branch 'sched/core' into locking/core
Required for the rtmutex/sched_deadline patches which depend on both
branches
2017-04-04 11:31:12 +02:00
Steven Rostedt (VMware) b80f0f6c9e ftrace: Have init/main.c call ftrace directly to free init memory
Relying on free_reserved_area() to call ftrace to free init memory proved to
not be sufficient. The issue is that on x86, when debug_pagealloc is
enabled, the init memory is not freed, but simply set as not present. Since
ftrace was uninformed of this, starting function tracing still tries to
update pages that are not present according to the page tables, causing
ftrace to bug, as well as killing the kernel itself.

Instead of relying on free_reserved_area(), have init/main.c call ftrace
directly just before it frees the init memory. Then it needs to use
__init_begin and __init_end to know where the init memory location is.
Looking at all archs (and testing what I can), it appears that this should
work for each of them.

Reported-by: kernel test robot <xiaolong.ye@intel.com>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-03 14:04:00 -04:00
Linus Torvalds 128c434a70 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Thomas Gleixner:
 "This update provides:

   - make the scheduler clock switch to unstable mode smooth so the
     timestamps stay at microseconds granularity instead of switching to
     tick granularity.

   - unbreak perf test tsc by taking the new offset into account which
     was added in order to proveide better sched clock continuity

   - switching sched clock to unstable mode runs all clock related
     computations which affect the sched clock output itself from a work
     queue. In case of preemption sched clock uses half updated data and
     provides wrong timestamps. Keep the math in the protected context
     and delegate only the static key switch to workqueue context.

   - remove a duplicate header include"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/headers: Remove duplicate #include <linux/sched/debug.h> line
  sched/clock: Fix broken stable to unstable transfer
  sched/clock, x86/perf: Fix "perf test tsc"
  sched/clock: Fix clear_sched_clock_stable() preempt wobbly
2017-04-02 09:25:10 -07:00
Al Viro bee3f412d6 Merge branch 'parisc-4.11-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux into uaccess.parisc 2017-04-02 10:33:48 -04:00
Alexei Starovoitov 1cf1cae963 bpf: introduce BPF_PROG_TEST_RUN command
development and testing of networking bpf programs is quite cumbersome.
Despite availability of user space bpf interpreters the kernel is
the ultimate authority and execution environment.
Current test frameworks for TC include creation of netns, veth,
qdiscs and use of various packet generators just to test functionality
of a bpf program. XDP testing is even more complicated, since
qemu needs to be started with gro/gso disabled and precise queue
configuration, transferring of xdp program from host into guest,
attaching to virtio/eth0 and generating traffic from the host
while capturing the results from the guest.

Moreover analyzing performance bottlenecks in XDP program is
impossible in virtio environment, since cost of running the program
is tiny comparing to the overhead of virtio packet processing,
so performance testing can only be done on physical nic
with another server generating traffic.

Furthermore ongoing changes to user space control plane of production
applications cannot be run on the test servers leaving bpf programs
stubbed out for testing.

Last but not least, the upstream llvm changes are validated by the bpf
backend testsuite which has no ability to test the code generated.

To improve this situation introduce BPF_PROG_TEST_RUN command
to test and performance benchmark bpf programs.

Joint work with Daniel Borkmann.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-01 12:45:57 -07:00
Daniel Borkmann 79adffcd64 bpf, verifier: fix rejection of unaligned access checks for map_value_adj
Currently, the verifier doesn't reject unaligned access for map_value_adj
register types. Commit 484611357c ("bpf: allow access into map value
arrays") added logic to check_ptr_alignment() extending it from PTR_TO_PACKET
to also PTR_TO_MAP_VALUE_ADJ, but for PTR_TO_MAP_VALUE_ADJ no enforcement
is in place, because reg->id for PTR_TO_MAP_VALUE_ADJ reg types is never
non-zero, meaning, we can cause BPF_H/_W/_DW-based unaligned access for
architectures not supporting efficient unaligned access, and thus worst
case could raise exceptions on some archs that are unable to correct the
unaligned access or perform a different memory access to the actual
requested one and such.

i) Unaligned load with !CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
   on r0 (map_value_adj):

   0: (bf) r2 = r10
   1: (07) r2 += -8
   2: (7a) *(u64 *)(r2 +0) = 0
   3: (18) r1 = 0x42533a00
   5: (85) call bpf_map_lookup_elem#1
   6: (15) if r0 == 0x0 goto pc+11
    R0=map_value(ks=8,vs=48,id=0),min_value=0,max_value=0 R10=fp
   7: (61) r1 = *(u32 *)(r0 +0)
   8: (35) if r1 >= 0xb goto pc+9
    R0=map_value(ks=8,vs=48,id=0),min_value=0,max_value=0 R1=inv,min_value=0,max_value=10 R10=fp
   9: (07) r0 += 3
  10: (79) r7 = *(u64 *)(r0 +0)
    R0=map_value_adj(ks=8,vs=48,id=0),min_value=3,max_value=3 R1=inv,min_value=0,max_value=10 R10=fp
  11: (79) r7 = *(u64 *)(r0 +2)
    R0=map_value_adj(ks=8,vs=48,id=0),min_value=3,max_value=3 R1=inv,min_value=0,max_value=10 R7=inv R10=fp
  [...]

ii) Unaligned store with !CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
    on r0 (map_value_adj):

   0: (bf) r2 = r10
   1: (07) r2 += -8
   2: (7a) *(u64 *)(r2 +0) = 0
   3: (18) r1 = 0x4df16a00
   5: (85) call bpf_map_lookup_elem#1
   6: (15) if r0 == 0x0 goto pc+19
    R0=map_value(ks=8,vs=48,id=0),min_value=0,max_value=0 R10=fp
   7: (07) r0 += 3
   8: (7a) *(u64 *)(r0 +0) = 42
    R0=map_value_adj(ks=8,vs=48,id=0),min_value=3,max_value=3 R10=fp
   9: (7a) *(u64 *)(r0 +2) = 43
    R0=map_value_adj(ks=8,vs=48,id=0),min_value=3,max_value=3 R10=fp
  10: (7a) *(u64 *)(r0 -2) = 44
    R0=map_value_adj(ks=8,vs=48,id=0),min_value=3,max_value=3 R10=fp
  [...]

For the PTR_TO_PACKET type, reg->id is initially zero when skb->data
was fetched, it later receives a reg->id from env->id_gen generator
once another register with UNKNOWN_VALUE type was added to it via
check_packet_ptr_add(). The purpose of this reg->id is twofold: i) it
is used in find_good_pkt_pointers() for setting the allowed access
range for regs with PTR_TO_PACKET of same id once verifier matched
on data/data_end tests, and ii) for check_ptr_alignment() to determine
that when not having efficient unaligned access and register with
UNKNOWN_VALUE was added to PTR_TO_PACKET, that we're only allowed
to access the content bytewise due to unknown unalignment. reg->id
was never intended for PTR_TO_MAP_VALUE{,_ADJ} types and thus is
always zero, the only marking is in PTR_TO_MAP_VALUE_OR_NULL that
was added after 484611357c via 57a09bf0a4 ("bpf: Detect identical
PTR_TO_MAP_VALUE_OR_NULL registers"). Above tests will fail for
non-root environment due to prohibited pointer arithmetic.

The fix splits register-type specific checks into their own helper
instead of keeping them combined, so we don't run into a similar
issue in future once we extend check_ptr_alignment() further and
forget to add reg->type checks for some of the checks.

Fixes: 484611357c ("bpf: allow access into map value arrays")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-01 12:36:37 -07:00
Daniel Borkmann fce366a9dd bpf, verifier: fix alu ops against map_value{, _adj} register types
While looking into map_value_adj, I noticed that alu operations
directly on the map_value() resp. map_value_adj() register (any
alu operation on a map_value() register will turn it into a
map_value_adj() typed register) are not sufficiently protected
against some of the operations. Two non-exhaustive examples are
provided that the verifier needs to reject:

 i) BPF_AND on r0 (map_value_adj):

  0: (bf) r2 = r10
  1: (07) r2 += -8
  2: (7a) *(u64 *)(r2 +0) = 0
  3: (18) r1 = 0xbf842a00
  5: (85) call bpf_map_lookup_elem#1
  6: (15) if r0 == 0x0 goto pc+2
   R0=map_value(ks=8,vs=48,id=0),min_value=0,max_value=0 R10=fp
  7: (57) r0 &= 8
  8: (7a) *(u64 *)(r0 +0) = 22
   R0=map_value_adj(ks=8,vs=48,id=0),min_value=0,max_value=8 R10=fp
  9: (95) exit

  from 6 to 9: R0=inv,min_value=0,max_value=0 R10=fp
  9: (95) exit
  processed 10 insns

ii) BPF_ADD in 32 bit mode on r0 (map_value_adj):

  0: (bf) r2 = r10
  1: (07) r2 += -8
  2: (7a) *(u64 *)(r2 +0) = 0
  3: (18) r1 = 0xc24eee00
  5: (85) call bpf_map_lookup_elem#1
  6: (15) if r0 == 0x0 goto pc+2
   R0=map_value(ks=8,vs=48,id=0),min_value=0,max_value=0 R10=fp
  7: (04) (u32) r0 += (u32) 0
  8: (7a) *(u64 *)(r0 +0) = 22
   R0=map_value_adj(ks=8,vs=48,id=0),min_value=0,max_value=0 R10=fp
  9: (95) exit

  from 6 to 9: R0=inv,min_value=0,max_value=0 R10=fp
  9: (95) exit
  processed 10 insns

Issue is, while min_value / max_value boundaries for the access
are adjusted appropriately, we change the pointer value in a way
that cannot be sufficiently tracked anymore from its origin.
Operations like BPF_{AND,OR,DIV,MUL,etc} on a destination register
that is PTR_TO_MAP_VALUE{,_ADJ} was probably unintended, in fact,
all the test cases coming with 484611357c ("bpf: allow access
into map value arrays") perform BPF_ADD only on the destination
register that is PTR_TO_MAP_VALUE_ADJ.

Only for UNKNOWN_VALUE register types such operations make sense,
f.e. with unknown memory content fetched initially from a constant
offset from the map value memory into a register. That register is
then later tested against lower / upper bounds, so that the verifier
can then do the tracking of min_value / max_value, and properly
check once that UNKNOWN_VALUE register is added to the destination
register with type PTR_TO_MAP_VALUE{,_ADJ}. This is also what the
original use-case is solving. Note, tracking on what is being
added is done through adjust_reg_min_max_vals() and later access
to the map value enforced with these boundaries and the given offset
from the insn through check_map_access_adj().

Tests will fail for non-root environment due to prohibited pointer
arithmetic, in particular in check_alu_op(), we bail out on the
is_pointer_value() check on the dst_reg (which is false in root
case as we allow for pointer arithmetic via env->allow_ptr_leaks).

Similarly to PTR_TO_PACKET, one way to fix it is to restrict the
allowed operations on PTR_TO_MAP_VALUE{,_ADJ} registers to 64 bit
mode BPF_ADD. The test_verifier suite runs fine after the patch
and it also rejects mentioned test cases.

Fixes: 484611357c ("bpf: allow access into map value arrays")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-01 12:36:37 -07:00
Steven Rostedt (VMware) 5bd84629a7 ftrace: Create separate t_func_next() to simplify the function / hash logic
I noticed that if I use dd to read the set_ftrace_filter file that the first
hash command is repeated.

 # cd /sys/kernel/debug/tracing
 # echo schedule > set_ftrace_filter
 # echo do_IRQ >> set_ftrace_filter
 # echo schedule:traceoff >> set_ftrace_filter
 # echo do_IRQ:traceoff >> set_ftrace_filter

 # cat set_ftrace_filter
 schedule
 do_IRQ
 schedule:traceoff:unlimited
 do_IRQ:traceoff:unlimited

 # dd if=set_ftrace_filter bs=1
 schedule
 do_IRQ
 schedule:traceoff:unlimited
 schedule:traceoff:unlimited
 do_IRQ:traceoff:unlimited
 98+0 records in
 98+0 records out
 98 bytes copied, 0.00265011 s, 37.0 kB/s

This is due to the way t_start() calls t_next() as well as the seq_file
calls t_next() and the state is slightly different between the two. Namely,
t_start() will call t_next() with a local "pos" variable.

By separating out the function listing from t_next() into its own function,
we can have better control of outputting the functions and the hash of
triggers. This simplifies the code.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-03-31 18:00:45 -04:00
Steven Rostedt (VMware) 43ff926a0c ftrace: Update func_pos in t_start() when all functions are enabled
If all functions are enabled, there's a comment displayed in the file to
denote that:

  # cd /sys/kernel/debug/tracing
  # cat set_ftrace_filter
 #### all functions enabled ####

If a function trigger is set, those are displayed as well:

  # echo schedule:traceoff >> /debug/tracing/set_ftrace_filter
  # cat set_ftrace_filter
 #### all functions enabled ####
 schedule:traceoff:unlimited

But if you read that file with dd, the output can change:

  # dd if=/debug/tracing/set_ftrace_filter bs=1
 #### all functions enabled ####
 32+0 records in
 32+0 records out
 32 bytes copied, 7.0237e-05 s, 456 kB/s

This is because the "pos" variable is updated for the comment, but func_pos
is not. "func_pos" is used by the triggers (or hashes) to know how many
functions were printed and it bases its index from the pos - func_pos.
func_pos should be 1 to count for the comment printed. But since it is not,
t_hash_start() thinks that one trigger was already printed.

The cat gets to t_hash_start() via t_next() and not t_start() which updates
both pos and func_pos.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-03-31 18:00:37 -04:00
Steven Rostedt (VMware) 2d71d98900 ftrace: Return NULL at end of t_start() instead of calling t_hash_start()
The loop in t_start() of calling t_next() will call t_hash_start() if the
pos is beyond the functions and enters the hash items. There's no reason to
check if p is NULL and call t_hash_start(), as that would be redundant.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-03-31 18:00:37 -04:00
Steven Rostedt (VMware) c20489dad1 ftrace: Assign iter->hash to filter or notrace hashes on seq read
Instead of testing if the hash to use is the filter_hash or the notrace_hash
at each iteration, do the test at open, and set the iter->hash to point to
the corresponding filter or notrace hash. Then use that directly instead of
testing which hash needs to be used each iteration.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-03-31 18:00:36 -04:00
Steven Rostedt (VMware) c1bc5919f6 ftrace: Clean up __seq_open_private() return check
The return status check of __seq_open_private() is rather strange:

	iter = __seq_open_private();
	if (iter) {
		/* do stuff */
	}

	return iter ? 0 : -ENOMEM;

It makes much more sense to do the return of failure right away:

	iter = __seq_open_private();
	if (!iter)
		return -ENOMEM;

	/* do stuff */

	return 0;

This clean up will make updates to this code a bit nicer.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-03-31 18:00:35 -04:00
Linus Torvalds 035f0cd3f8 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fixes from Herbert Xu:
 "This fixes the following issues:

   - memory corruption when kmalloc fails in xts/lrw

   - mark some CCP DMA channels as private

   - fix reordering race in padata

   - regression in omap-rng DT description"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: xts,lrw - fix out-of-bounds write after kmalloc failure
  crypto: ccp - Make some CCP DMA channels private
  padata: avoid race in reordering
  dt-bindings: rng: clocks property on omap_rng not always mandatory
2017-03-31 12:11:32 -07:00
Nicholas Mc Guire 5fc63f9577 timekeeping: Remove pointless conversion to bool
interp_forward is type bool so assignment from a logical operation directly
is sufficient.

Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at>
Cc: "Christopher S. Hall" <christopher.s.hall@intel.com>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/1490382215-30505-1-git-send-email-der.herr@hofr.at
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-31 10:26:56 +02:00
Thomas Gleixner 9005615baf Merge branch 'fortglx/4.12/time' of https://git.linaro.org/people/john.stultz/linux into timers/core
Pull timekeeping changes from John Stultz:

 Main changes are the initial steps of Nicoli's work to make the clockevent
 timers be corrected for NTP adjustments. Then a few smaller fixes that
 I've queued, and adding Stephen Boyd to the maintainers list for
 timekeeping.
2017-03-31 09:48:00 +02:00
Zhou Chengming 72f04b50d6 livepatch: Reduce the time of finding module symbols
It's reported that the time of insmoding a klp.ko for one of our
out-tree modules is too long.

~ time sudo insmod klp.ko
real	0m23.799s
user	0m0.036s
sys	0m21.256s

Then we found the reason: our out-tree module used a lot of static local
variables, so klp.ko has a lot of relocation records which reference the
module. Then for each such entry klp_find_object_symbol() is called to
resolve it, but this function uses the interface kallsyms_on_each_symbol()
even for finding module symbols, so will waste a lot of time on walking
through vmlinux kallsyms table many times.

This patch changes it to use module_kallsyms_on_each_symbol() for modules
symbols. After we apply this patch, the sys time reduced dramatically.

~ time sudo insmod klp.ko
real	0m1.007s
user	0m0.032s
sys	0m0.924s

Signed-off-by: Zhou Chengming <zhouchengming1@huawei.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Jessica Yu <jeyu@redhat.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2017-03-30 10:41:38 +02:00
Chris Wilson 57dd924e54 locking/ww-mutex: Limit stress test to 2 seconds
Use a timeout rather than a fixed number of loops to avoid running for
very long periods, such as under the kbuilder VMs.

Reported-by: kernel test robot <xiaolong.ye@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170310105733.6444-1-chris@chris-wilson.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-30 09:49:47 +02:00
Ingo Molnar c69f203df3 Merge branch 'linus' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-30 09:48:58 +02:00
Yuyang Du a481db34b9 sched/fair: Optimize ___update_sched_avg()
The main PELT function ___update_load_avg(), which implements the
accumulation and progression of the geometric average series, is
implemented along the following lines for the scenario where the time
delta spans all 3 possible sections (see figure below):

  1. add the remainder of the last incomplete period
  2. decay old sum
  3. accumulate new sum in full periods since last_update_time
  4. accumulate the current incomplete period
  5. update averages

Or:

            d1          d2           d3
            ^           ^            ^
            |           |            |
          |<->|<----------------->|<--->|
  ... |---x---|------| ... |------|-----x (now)

  load_sum' = (load_sum + weight * scale * d1) * y^(p+1) +	(1,2)

                                        p
	      weight * scale * 1024 * \Sum y^n +		(3)
                                       n=1

	      weight * scale * d3 * y^0				(4)

  load_avg' = load_sum' / LOAD_AVG_MAX				(5)

Where:

 d1 - is the delta part completing the remainder of the last
      incomplete period,
 d2 - is the delta part spannind complete periods, and
 d3 - is the delta part starting the current incomplete period.

We can simplify the code in two steps; the first step is to separate
the first term into new and old parts like:

  (load_sum + weight * scale * d1) * y^(p+1) = load_sum * y^(p+1) +
					       weight * scale * d1 * y^(p+1)

Once we've done that, its easy to see that all new terms carry the
common factors:

  weight * scale

If we factor those out, we arrive at the form:

  load_sum' = load_sum * y^(p+1) +

	      weight * scale * (d1 * y^(p+1) +

					 p
			        1024 * \Sum y^n +
					n=1

				d3 * y^0)

Which results in a simpler, smaller and faster implementation.

Signed-off-by: Yuyang Du <yuyang.du@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bsegall@google.com
Cc: dietmar.eggemann@arm.com
Cc: matt@codeblueprint.co.uk
Cc: morten.rasmussen@arm.com
Cc: pjt@google.com
Cc: umgwanakikbuti@gmail.com
Cc: vincent.guittot@linaro.org
Link: http://lkml.kernel.org/r/1486935863-25251-3-git-send-email-yuyang.du@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-30 09:43:41 +02:00
Peter Zijlstra 0ccb977f4c sched/fair: Explicitly generate __update_load_avg() instances
The __update_load_avg() function is an __always_inline because its
used with constant propagation to generate different variants of the
code without having to duplicate it (which would be prone to bugs).

Explicitly instantiate the 3 variants.

Note that most of this is called from rather hot paths, so reducing
branches is good.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-30 09:43:40 +02:00
Al Viro db68ce10c4 new helper: uaccess_kernel()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-03-28 16:43:25 -04:00
Dave Airlie e5c1ff1475 Linux 4.11-rc4
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Backmerge tag 'v4.11-rc4' into drm-next

Linux 4.11-rc4

The i915 GVT team need the rc4 code to base some more code on.
2017-03-28 17:34:19 +10:00
Ingo Molnar d652f4bbca Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-28 07:44:25 +02:00
Tetsuo Handa e4e55b47ed LSM: Revive security_task_alloc() hook and per "struct task_struct" security blob.
We switched from "struct task_struct"->security to "struct cred"->security
in Linux 2.6.29. But not all LSM modules were happy with that change.
TOMOYO LSM module is an example which want to use per "struct task_struct"
security blob, for TOMOYO's security context is defined based on "struct
task_struct" rather than "struct cred". AppArmor LSM module is another
example which want to use it, for AppArmor is currently abusing the cred
a little bit to store the change_hat and setexeccon info. Although
security_task_free() hook was revived in Linux 3.4 because Yama LSM module
wanted to release per "struct task_struct" security blob,
security_task_alloc() hook and "struct task_struct"->security field were
not revived. Nowadays, we are getting proposals of lightweight LSM modules
which want to use per "struct task_struct" security blob.

We are already allowing multiple concurrent LSM modules (up to one fully
armored module which uses "struct cred"->security field or exclusive hooks
like security_xfrm_state_pol_flow_match(), plus unlimited number of
lightweight modules which do not use "struct cred"->security nor exclusive
hooks) as long as they are built into the kernel. But this patch does not
implement variable length "struct task_struct"->security field which will
become needed when multiple LSM modules want to use "struct task_struct"->
security field. Although it won't be difficult to implement variable length
"struct task_struct"->security field, let's think about it after we merged
this patch.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: John Johansen <john.johansen@canonical.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Tested-by: Djalal Harouni <tixxdz@gmail.com>
Acked-by: José Bollo <jobol@nonadev.net>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Eric Paris <eparis@parisplace.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: James Morris <james.l.morris@oracle.com>
Cc: José Bollo <jobol@nonadev.net>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-03-28 11:05:14 +11:00
James Morris 840c91dc6a update to v4.11-rc4 due to memory corruption bug in rc2 2017-03-28 11:03:35 +11:00
Paul Moore ab6434a137 audit: move audit_signal_info() into kernel/auditsc.c
Commit 5b52330bbf ("audit: fix auditd/kernel connection state
tracking") made inlining audit_signal_info() a bit pointless as
it was always calling into auditd_test_task() so let's remove the
inline function in kernel/audit.h and convert __audit_signal_info()
in kernel/auditsc.c into audit_signal_info().

Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-03-27 14:30:06 -04:00
Nicholas Mc Guire 75fa8e5d3b cgroup: switch to BUG_ON()
Use BUG_ON() rather than an explicit if followed by BUG() for
improved readability and also consistency.

Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-03-27 13:59:12 -04:00
Pavel Tatashin 7b09cc5a9d sched/clock: Fix broken stable to unstable transfer
When it is determined that the clock is actually unstable, and
we switch from stable to unstable, the __clear_sched_clock_stable()
function is eventually called.

In this function we set gtod_offset so the following holds true:

  sched_clock() + raw_offset == ktime_get_ns() + gtod_offset

But instead of getting the latest timestamps, we use the last values
from scd, so instead of sched_clock() we use scd->tick_raw, and
instead of ktime_get_ns() we use scd->tick_gtod.

However, later, when we use gtod_offset sched_clock_local() we do not
add it to scd->tick_gtod to calculate the correct clock value when we
determine the boundaries for min/max clocks.

This can result in tick granularity sched_clock() values, so fix it.

Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hpa@zytor.com
Fixes: 5680d8094f ("sched/clock: Provide better clock continuity")
Link: http://lkml.kernel.org/r/1490214265-899964-2-git-send-email-pasha.tatashin@oracle.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-27 10:23:48 +02:00
Srikar Dronamraju 05b40e0577 sched/fair: Prefer sibiling only if local group is under-utilized
If the child domain prefers tasks to go siblings, the local group could
end up pulling tasks to itself even if the local group is almost equally
loaded as the source group.

Lets assume a 4 core,smt==2 machine running 5 thread ebizzy workload.
Everytime, local group has capacity and source group has atleast 2 threads,
local group tries to pull the task. This causes the threads to constantly
move between different cores. This is even more profound if the cores have
more threads, like in Power 8, smt 8 mode.

Fix this by only allowing local group to pull a task, if the source group
has more number of tasks than the local group.

Here are the relevant perf stat numbers of a 22 core,smt 8 Power 8 machine.

Without patch:
 Performance counter stats for 'ebizzy -t 22 -S 100' (5 runs):

             1,440      context-switches          #    0.001 K/sec                    ( +-  1.26% )
               366      cpu-migrations            #    0.000 K/sec                    ( +-  5.58% )
             3,933      page-faults               #    0.002 K/sec                    ( +- 11.08% )

 Performance counter stats for 'ebizzy -t 48 -S 100' (5 runs):

             6,287      context-switches          #    0.001 K/sec                    ( +-  3.65% )
             3,776      cpu-migrations            #    0.001 K/sec                    ( +-  4.84% )
             5,702      page-faults               #    0.001 K/sec                    ( +-  9.36% )

 Performance counter stats for 'ebizzy -t 96 -S 100' (5 runs):

             8,776      context-switches          #    0.001 K/sec                    ( +-  0.73% )
             2,790      cpu-migrations            #    0.000 K/sec                    ( +-  0.98% )
            10,540      page-faults               #    0.001 K/sec                    ( +-  3.12% )

With patch:

 Performance counter stats for 'ebizzy -t 22 -S 100' (5 runs):

             1,133      context-switches          #    0.001 K/sec                    ( +-  4.72% )
               123      cpu-migrations            #    0.000 K/sec                    ( +-  3.42% )
             3,858      page-faults               #    0.002 K/sec                    ( +-  8.52% )

 Performance counter stats for 'ebizzy -t 48 -S 100' (5 runs):

             2,169      context-switches          #    0.000 K/sec                    ( +-  6.19% )
               189      cpu-migrations            #    0.000 K/sec                    ( +- 12.75% )
             5,917      page-faults               #    0.001 K/sec                    ( +-  8.09% )

 Performance counter stats for 'ebizzy -t 96 -S 100' (5 runs):

             5,333      context-switches          #    0.001 K/sec                    ( +-  5.91% )
               506      cpu-migrations            #    0.000 K/sec                    ( +-  3.35% )
            10,792      page-faults               #    0.001 K/sec                    ( +-  7.75% )

Which show that in these workloads CPU migrations get reduced significantly.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Link: http://lkml.kernel.org/r/1490205470-10249-1-git-send-email-srikar@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-27 10:22:26 +02:00
Peter Zijlstra 8ce371f984 lockdep: Fix per-cpu static objects
Since commit 383776fa75 ("locking/lockdep: Handle statically initialized
PER_CPU locks properly") we try to collapse per-cpu locks into a single
class by giving them all the same key. For this key we choose the canonical
address of the per-cpu object, which would be the offset into the per-cpu
area.

This has two problems:

 - there is a case where we run !0 lock->key through static_obj() and
   expect this to pass; it doesn't for canonical pointers.

 - 0 is a valid canonical address.

Cure both issues by redefining the canonical address as the address of the
per-cpu variable on the boot CPU.

Since I didn't want to rely on CPU0 being the boot-cpu, or even existing at
all, track the boot CPU in a variable.

Fixes: 383776fa75 ("locking/lockdep: Handle statically initialized PER_CPU locks properly")
Reported-by: kernel test robot <fengguang.wu@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Borislav Petkov <bp@suse.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-mm@kvack.org
Cc: wfg@linux.intel.com
Cc: kernel test robot <fengguang.wu@intel.com>
Cc: LKP <lkp@01.org>
Link: http://lkml.kernel.org/r/20170320114108.kbvcsuepem45j5cr@hirez.programming.kicks-ass.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-26 15:09:45 +02:00
Linus Torvalds 4c3de7e5bf Merge branch 'stable-4.11' of git://git.infradead.org/users/pcmoore/audit
Pull audit fix from Paul Moore:
 "We've got an audit fix, and unfortunately it is big.

  While I'm not excited that we need to be sending you something this
  large during the -rcX phase, it does fix some very real, and very
  tangled, problems relating to locking, backlog queues, and the audit
  daemon connection.

  This code has passed our testsuite without problem and it has held up
  to my ad-hoc stress tests (arguably better than the existing code),
  please consider pulling this as fix for the next v4.11-rcX tag"

* 'stable-4.11' of git://git.infradead.org/users/pcmoore/audit:
  audit: fix auditd/kernel connection state tracking
2017-03-25 15:13:55 -07:00
Alexei Starovoitov b1977682a3 bpf: improve verifier packet range checks
llvm can optimize the 'if (ptr > data_end)' checks to be in the order
slightly different than the original C code which will confuse verifier.
Like:
if (ptr + 16 > data_end)
  return TC_ACT_SHOT;
// may be followed by
if (ptr + 14 > data_end)
  return TC_ACT_SHOT;
while llvm can see that 'ptr' is valid for all 16 bytes,
the verifier could not.
Fix verifier logic to account for such case and add a test.

Reported-by: Huapeng Zhou <hzhou@fb.com>
Fixes: 969bf05eb3 ("bpf: direct packet access")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-24 20:51:28 -07:00
Rafael J. Wysocki 70e493f3bb Merge back schedutil governor updates for 4.12. 2017-03-25 02:35:48 +01:00
Steven Rostedt (VMware) af0009fc16 tracing: Move trace_handle_return() out of line
Currently trace_handle_return() looks like this:

 static inline enum print_line_t trace_handle_return(struct trace_seq *s)
 {
        return trace_seq_has_overflowed(s) ?
                TRACE_TYPE_PARTIAL_LINE : TRACE_TYPE_HANDLED;
 }

Where trace_seq_overflowed(s) is:

 static inline bool trace_seq_has_overflowed(struct trace_seq *s)
 {
	return s->full || seq_buf_has_overflowed(&s->seq);
 }

And seq_buf_has_overflowed(&s->seq) is:

 static inline bool
 seq_buf_has_overflowed(struct seq_buf *s)
 {
	return s->len > s->size;
 }

Making trace_handle_return() into:

 return (s->full || (s->seq->len > s->seq->size)) ?
           TRACE_TYPE_PARTIAL_LINE :
           TRACE_TYPE_HANDLED;

One would think this is not an issue to keep as an inline. But because this
is used in the TRACE_EVENT() macro, it is extended for every tracepoint in
the system. Taking a look at a single tracepoint x86_irq_vector (was the
first one I randomly chosen). As trace_handle_return is used in the
TRACE_EVENT() macro of trace_raw_output_##call() we disassemble
trace_raw_output_x86_irq_vector and do a diff:

- is the original
+ is the out-of-line code

I removed identical lines that were different just due to different
addresses.

--- /tmp/irq-vec-orig	2017-03-16 09:12:48.569384851 -0400
+++ /tmp/irq-vec-ool	2017-03-16 09:13:39.378153385 -0400
@@ -6,27 +6,23 @@
        53                      push   %rbx
        48 89 fb                mov    %rdi,%rbx
        4c 8b a7 c0 20 00 00    mov    0x20c0(%rdi),%r12
        e8 f7 72 13 00          callq  ffffffff81155c80 <trace_raw_output_prep>
        83 f8 01                cmp    $0x1,%eax
        74 05                   je     ffffffff8101e993 <trace_raw_output_x86_irq_vector+0x23>
        5b                      pop    %rbx
        41 5c                   pop    %r12
        5d                      pop    %rbp
        c3                      retq
        41 8b 54 24 08          mov    0x8(%r12),%edx
-       48 8d bb 98 10 00 00    lea    0x1098(%rbx),%rdi
+       48 81 c3 98 10 00 00    add    $0x1098,%rbx
-       48 c7 c6 7b 8a a0 81    mov    $0xffffffff81a08a7b,%rsi
+       48 c7 c6 ab 8a a0 81    mov    $0xffffffff81a08aab,%rsi
-       e8 c5 85 13 00          callq  ffffffff81156f70 <trace_seq_printf>

 === here's the start of the main difference ===

+       48 89 df                mov    %rbx,%rdi
+       e8 62 7e 13 00          callq  ffffffff81156810 <trace_seq_printf>
-       8b 93 b8 20 00 00       mov    0x20b8(%rbx),%edx
-       31 c0                   xor    %eax,%eax
-       85 d2                   test   %edx,%edx
-       75 11                   jne    ffffffff8101e9c8 <trace_raw_output_x86_irq_vector+0x58>
-       48 8b 83 a8 20 00 00    mov    0x20a8(%rbx),%rax
-       48 39 83 a0 20 00 00    cmp    %rax,0x20a0(%rbx)
-       0f 93 c0                setae  %al
+       48 89 df                mov    %rbx,%rdi
+       e8 4a c5 12 00          callq  ffffffff8114af00 <trace_handle_return>
        5b                      pop    %rbx
-       0f b6 c0                movzbl %al,%eax

 === end ===

        41 5c                   pop    %r12
        5d                      pop    %rbp
        c3                      retq

If you notice, the original has 22 bytes of text more than the out of line
version. As this is for every TRACE_EVENT() defined in the system, this can
become quite large.

   text	   data	    bss	    dec	    hex	filename
8690305	5450490	1298432	15439227	 eb957b	vmlinux-orig
8681725	5450490	1298432	15430647	 eb73f7	vmlinux-handle

This change has a total of 8580 bytes in savings.

 $ objdump -dr /tmp/vmlinux-orig | grep '^[0-9a-f]* <trace_raw_output' | wc -l
324

That's 324 tracepoints. But this does not include modules (which contain
many more tracepoints). For an allyesconfig build:

 $ objdump -dr vmlinux-allyes-orig | grep '^[0-9a-f]* <trace_raw_output' | wc -l
1401

That's 1401 tracepoints giving us:

   text    data     bss     dec     hex filename
137920629       140221067       53264384        331406080       13c0db00 vmlinux-allyes-orig
137827709       140221067       53264384        331313160       13bf7008 vmlinux-allyes-handle

92920 bytes in savings!!!

Link: http://lkml.kernel.org/r/20170315021431.13107-2-andi@firstfloor.org

Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-03-24 20:51:50 -04:00
Steven Rostedt (VMware) 42c269c88d ftrace: Allow for function tracing to record init functions on boot up
Adding a hook into free_reserve_area() that informs ftrace that boot up init
text is being free, lets ftrace safely remove those init functions from its
records, which keeps ftrace from trying to modify text that no longer
exists.

Note, this still does not allow for tracing .init text of modules, as
modules require different work for freeing its init code.

Link: http://lkml.kernel.org/r/1488502497.7212.24.camel@linux.intel.com

Cc: linux-mm@kvack.org
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Requested-by: Todd Brandt <todd.e.brandt@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-03-24 20:51:49 -04:00
Steven Rostedt (VMware) dbeafd0d61 ftrace: Have function tracing start in early boot up
Register the function tracer right after the tracing buffers are initialized
in early boot up. This will allow function tracing to begin early if it is
enabled via the kernel command line.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-03-24 20:51:48 -04:00