There were discussions in the past about use cases for
simple_strto<foo>() functions and, in some rare cases, they have a
benefit over kstrto<foo>() ones.
Update a comment to reduce confusion about special use cases.
Link: http://lkml.kernel.org/r/20190801192904.41087-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Suggested-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Mans Rullgard <mans@mansr.com>
Cc: Petr Mladek <pmladek@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In some special cases we must not block, but there's not a spinlock,
preempt-off, irqs-off or similar critical section already that arms the
might_sleep() debug checks. Add a non_block_start/end() pair to annotate
these.
This will be used in the oom paths of mmu-notifiers, where blocking is not
allowed to make sure there's forward progress. Quoting Michal:
"The notifier is called from quite a restricted context - oom_reaper -
which shouldn't depend on any locks or sleepable conditionals. The code
should be swift as well but we mostly do care about it to make a forward
progress. Checking for sleepable context is the best thing we could come
up with that would describe these demands at least partially."
Peter also asked whether we want to catch spinlocks on top, but Michal
said those are less of a problem because spinlocks can't have an indirect
dependency upon the page allocator and hence close the loop with the oom
reaper.
Suggested by Michal Hocko.
Link: https://lore.kernel.org/r/20190826201425.17547-4-daniel.vetter@ffwll.ch
Acked-by: Christian König <christian.koenig@amd.com> (v1)
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Add typeof_member() macro so that types can be extracted without
introducing dummy variables.
Link: http://lkml.kernel.org/r/20190529190720.GA5703@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
DIV_ROUND_UP_ULL adds the two arguments and then invokes
DIV_ROUND_DOWN_ULL. But on a 32bit system the addition of two 32 bit
values can overflow. DIV_ROUND_DOWN_ULL does it correctly and stashes
the addition into a unsigned long long so cast the result to unsigned
long long here to avoid the overflow condition.
[akpm@linux-foundation.org: DIV_ROUND_UP_ULL must be an rval]
Link: http://lkml.kernel.org/r/20190625100518.30753-1-vkoul@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The integer exponentiation is used in few places and might be used in
the future by other call sites. Move it to wider use.
Link: http://lkml.kernel.org/r/20190323172531.80025-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Ray Jui <rjui@broadcom.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge tag 'v5.1-rc6' into for-5.2/block
Pull in v5.1-rc6 to resolve two conflicts. One is in BFQ, in just a
comment, and is trivial. The other one is a conflict due to a later fix
in the bio multi-page work, and needs a bit more care.
* tag 'v5.1-rc6': (770 commits)
Linux 5.1-rc6
block: make sure that bvec length can't be overflow
block: kill all_q_node in request_queue
x86/cpu/intel: Lower the "ENERGY_PERF_BIAS: Set to normal" message's log priority
coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping
mm/kmemleak.c: fix unused-function warning
init: initialize jump labels before command line option parsing
kernel/watchdog_hld.c: hard lockup message should end with a newline
kcov: improve CONFIG_ARCH_HAS_KCOV help text
mm: fix inactive list balancing between NUMA nodes and cgroups
mm/hotplug: treat CMA pages as unmovable
proc: fixup proc-pid-vm test
proc: fix map_files test on F29
mm/vmstat.c: fix /proc/vmstat format for CONFIG_DEBUG_TLBFLUSH=y CONFIG_SMP=n
mm/memory_hotplug: do not unlock after failing to take the device_hotplug_lock
mm: swapoff: shmem_unuse() stop eviction without igrab()
mm: swapoff: take notice of completion sooner
mm: swapoff: remove too limiting SWAP_UNUSE_MAX_TRIES
mm: swapoff: shmem_find_swap_entries() filter out other types
slab: store tagged freelist for off-slab slabmgmt
...
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently support for 64-bit sector_t and blkcnt_t is optional on 32-bit
architectures. These types are required to support block device and/or
file sizes larger than 2 TiB, and have generally defaulted to on for
a long time. Enabling the option only increases the i386 tinyconfig
size by 145 bytes, and many data structures already always use
64-bit values for their in-core and on-disk data structures anyway,
so there should not be a large change in dynamic memory usage either.
Dropping this option removes a somewhat weird non-default config that
has cause various bugs or compiler warnings when actually used.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use parentheses around uses of the argument in u64_to_user_ptr() to
ensure that the cast doesn't apply to part of the argument.
There are existing uses of the macro of the form
u64_to_user_ptr(A + B)
which expands to
(void __user *)(uintptr_t)A + B
(the cast applies to the first operand of the addition, the addition
is a pointer addition). This happens to still work as intended, the
semantic difference doesn't cause a difference in behavior.
But I want to use u64_to_user_ptr() with a ternary operator in the
argument, like so:
u64_to_user_ptr(A ? B : C)
This currently doesn't work as intended.
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Cc: Andrei Vagin <avagin@openvz.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: NeilBrown <neilb@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Qiaowei Ren <qiaowei.ren@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190329214652.258477-1-jannh@google.com
<linux/kernel.h> tends to be cluttered because we often put various sort
of unrelated stuff in it. So, we have split out a sensible chunk of
code into a separate header from time to time.
This commit splits out the *_MAX and *_MIN defines.
The standard header <limits.h> contains various MAX, MIN constants
including numerial limits. [1]
I think it makes sense to move in-kernel MAX, MIN constants into
include/linux/limits.h.
We already have include/uapi/linux/limits.h to contain some user-space
constants. I changed its include guard to _UAPI_LINUX_LIMITS_H. This
change has no impact to the user-space because
scripts/headers_install.sh rips off the '_UAPI' prefix from the include
guards of exported headers.
[1] http://pubs.opengroup.org/onlinepubs/009604499/basedefs/limits.h.html
Link: http://lkml.kernel.org/r/1549156242-20806-2-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Alex Elder <elder@linaro.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Zhang Yanmin <yanmin.zhang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The commit log of 44f564a4bf ("ipc: add definitions of USHORT_MAX and
others") did not explain why it used (s16) and (u16) instead of (short)
and (unsigned short).
Let's use (short) and (unsigned short), which is more sensible, and more
consistent with the other MAX/MIN defines.
As you see in include/uapi/asm-generic/int-ll64.h, s16/u16 are
typedef'ed as signed/unsigned short. So, this commit does not have a
functional change.
Remove the unneeded parentheses around ~0U while we are here.
Link: http://lkml.kernel.org/r/1549156242-20806-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Zhang Yanmin <yanmin.zhang@intel.com>
Cc: Alex Elder <elder@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The single quotation marks around "const" were causing a documentation
markup warning with reST. Instead of fixing that warning, just delete
that comment line and the gcc-3.3 hack of using "const" in the roundup()
macro since gcc-3.3 is no longer supported for kernel builds.
I did around 20 different $arch builds with no problems, but we'll just
have to see if this causes problems for anyone else out there.
Link: http://lkml.kernel.org/r/ec5dcf72-7c3e-3513-af0c-4003ed598854@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Include asm/div64.h for do_div() usage in DIV_ROUND_DOWN_ULL() and
DIV_ROUND_CLOSEST_ULL(). Remove the old CONFIG_LBDAF=y conditional
include.
Link: http://lkml.kernel.org/r/20181228153430.23763-1-jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Introduce cant_sleep() macro for annotation of functions that
cannot sleep.
Use it in BPF_PROG_RUN to catch execution of BPF programs in
preemptable context.
Suggested-by: Jann Horn <jannh@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
So that we can also runtime chose to print out the needed system info
for panic, other than setting the kernel cmdline.
Link: http://lkml.kernel.org/r/1543398842-19295-3-git-send-email-feng.tang@intel.com
Signed-off-by: Feng Tang <feng.tang@intel.com>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Things like 3619dec510 ("dh key: fix rounding up KDF output length")
expose the lack of explicit documentation for roundup() vs round_up(). At
least we can try to document it better if anyone goes looking.
Link: http://lkml.kernel.org/r/20180703041950.GA43464@beast
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Here is the big staging and IIO driver update for 4.18-rc1.
It was delayed as I wanted to make sure the final driver deletions did
not cause any major merge issues, and all now looks good.
There are a lot of patches here, just over 1000. The diffstat summary
shows the major changes here:
1007 files changed, 16828 insertions(+), 227770 deletions(-)
Because of this, we might be close to shrinking the overall kernel
source code size for two releases in a row.
There was loads of work in this release cycle, primarily:
- tons of ks7010 driver cleanups
- lots of mt7621 driver fixes and cleanups
- most driver cleanups
- wilc1000 fixes and cleanups
- lots and lots of IIO driver cleanups and new additions
- debugfs cleanups for all staging drivers
- lots of other staging driver cleanups and fixes, the shortlog
has the full details.
but the big user-visable things here are the removal of 3 chunks of
code:
- ncpfs and ipx were removed on schedule, no one has cared about
this code since it moved to staging last year, and if it needs
to come back, it can be reverted.
- lustre file system is removed. I've ranted at the lustre
developers about once a year for the past 5 years, with no
real forward progress at all to clean things up and get the
code into the "real" part of the kernel. Given that the
lustre developers continue to work on an external tree and try
to port those changes to the in-kernel tree every once in a
while, this whole thing really really is not working out at
all. So I'm deleting it so that the developers can spend the
time working in their out-of-tree location and get things
cleaned up properly to get merged into the tree correctly at a
later date.
Because of these file removals, you will have merge issues on some of
these files (2 in the ipx code, 1 in the ncpfs code, and 1 in the
atomisp driver). Just delete those files, it's a simple merge :)
All of this has been in linux-next for a while with no reported
problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging/IIO updates from Greg KH:
"Here is the big staging and IIO driver update for 4.18-rc1.
It was delayed as I wanted to make sure the final driver deletions did
not cause any major merge issues, and all now looks good.
There are a lot of patches here, just over 1000. The diffstat summary
shows the major changes here:
1007 files changed, 16828 insertions(+), 227770 deletions(-)
Because of this, we might be close to shrinking the overall kernel
source code size for two releases in a row.
There was loads of work in this release cycle, primarily:
- tons of ks7010 driver cleanups
- lots of mt7621 driver fixes and cleanups
- most driver cleanups
- wilc1000 fixes and cleanups
- lots and lots of IIO driver cleanups and new additions
- debugfs cleanups for all staging drivers
- lots of other staging driver cleanups and fixes, the shortlog has
the full details.
but the big user-visable things here are the removal of 3 chunks of
code:
- ncpfs and ipx were removed on schedule, no one has cared about this
code since it moved to staging last year, and if it needs to come
back, it can be reverted.
- lustre file system is removed.
I've ranted at the lustre developers about once a year for the past
5 years, with no real forward progress at all to clean things up
and get the code into the "real" part of the kernel.
Given that the lustre developers continue to work on an external
tree and try to port those changes to the in-kernel tree every once
in a while, this whole thing really really is not working out at
all. So I'm deleting it so that the developers can spend the time
working in their out-of-tree location and get things cleaned up
properly to get merged into the tree correctly at a later date.
Because of these file removals, you will have merge issues on some of
these files (2 in the ipx code, 1 in the ncpfs code, and 1 in the
atomisp driver). Just delete those files, it's a simple merge :)
All of this has been in linux-next for a while with no reported
problems"
* tag 'staging-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1011 commits)
staging: ipx: delete it from the tree
ncpfs: remove uapi .h files
ncpfs: remove Documentation
ncpfs: remove compat functionality
staging: ncpfs: delete it
staging: lustre: delete the filesystem from the tree.
staging: vc04_services: no need to save the log debufs dentries
staging: vc04_services: vchiq_debugfs_log_entry can be a void *
staging: vc04_services: remove struct vchiq_debugfs_info
staging: vc04_services: move client dbg directory into static variable
staging: vc04_services: remove odd vchiq_debugfs_top() wrapper
staging: vc04_services: no need to check debugfs return values
staging: mt7621-gpio: reorder includes alphabetically
staging: mt7621-gpio: change gc_map to don't use pointers
staging: mt7621-gpio: use GPIOF_DIR_OUT and GPIOF_DIR_IN macros instead of custom values
staging: mt7621-gpio: change 'to_mediatek_gpio' to make just a one line return
staging: mt7621-gpio: dt-bindings: update documentation for #interrupt-cells property
staging: mt7621-gpio: update #interrupt-cells for the gpio node
staging: mt7621-gpio: dt-bindings: complete documentation for the gpio
staging: mt7621-dts: add missing properties to gpio node
...
So far code was using ULLONG_MAX and type casting to obtain a
phys_addr_t with all bits set. The typecast is necessary to silence
compiler warnings on 32-bit platforms.
Use the simpler but still type safe approach "~(phys_addr_t)0" to create a
preprocessor define for all bits set.
Link: http://lkml.kernel.org/r/20180406213809.566-1-stefan@agner.ch
Signed-off-by: Stefan Agner <stefan@agner.ch>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
timekeeping suspend/resume calls read_persistent_clock() which takes
rtc_lock. That results in might sleep warnings because at that point
we run with interrupts disabled.
We cannot convert rtc_lock to a raw spinlock as that would trigger
other might sleep warnings.
As a workaround we disable the might sleep warnings by setting
system_state to SYSTEM_SUSPEND before calling sysdev_suspend() and
restoring it to SYSTEM_RUNNING afer sysdev_resume(). There is no lock
contention because hibernate / suspend to RAM is single-CPU at this
point.
In s2idle's case the system_state is set to SYSTEM_SUSPEND before
timekeeping_suspend() which is invoked by the last CPU. In the resume
case it set back to SYSTEM_RUNNING after timekeeping_resume() which is
invoked by the first CPU in the resume case. The other CPUs will block
on tick_freeze_lock.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[bigeasy: cover s2idle in tick_freeze() / tick_unfreeze()]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There aren't many users of this so it doesn't cause a problem, but we
obviously want to use "__mptr" here instead of "ptr" to prevent the
parameter from being executed twice.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: NeilBrown <neilb@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Luster has a container_of0() function which is similar to
container_of() but passes an IS_ERR_OR_NULL() pointer through
unchanged.
This could be generally useful: bcache at last has a similar function.
Naming is hard, but the precedent set by hlist_entry_safe() suggests
a _safe suffix might be most consistent.
So add container_of_safe() to kernel.h, and replace all occurrences of
container_of0() with one of
- list_first_entry, list_next_entry, when that is a better fit,
- container_of(), when the pointer is used as a validpointer in
surrounding code,
- container_of_safe() when there is no obviously better alternative.
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since the randstruct plugin can intentionally produce extremely unusual
kernel structure layouts (even performance pathological ones), some
maintainers want to be able to trivially determine if an Oops is coming
from a randstruct-built kernel, so as to keep their sanity when
debugging. This adds the new flag and initializes taint_mask
immediately when built with randstruct.
Link: http://lkml.kernel.org/r/1519084390-43867-4-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This converts to using indexed initializers instead of comments, adds a
comment on why the taint flags can't be an enum, and make sure that no
one forgets to update the taint_flags when adding new bits.
Link: http://lkml.kernel.org/r/1519084390-43867-2-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
seq_put_decimal_ull_w(m, str, val, width) prints a decimal number with a
specified minimal field width.
It is equivalent of seq_printf(m, "%s%*d", str, width, val), but it
works much faster.
== test_smaps.py
num = 0
with open("/proc/1/smaps") as f:
for x in xrange(10000):
data = f.read()
f.seek(0, 0)
==
== Before patch ==
$ time python test_smaps.py
real 0m4.593s
user 0m0.398s
sys 0m4.158s
== After patch ==
$ time python test_smaps.py
real 0m3.828s
user 0m0.413s
sys 0m3.408s
$ perf -g record python test_smaps.py
== Before patch ==
- 79.01% 3.36% python [kernel.kallsyms] [k] show_smap.isra.33
- 75.65% show_smap.isra.33
+ 48.85% seq_printf
+ 15.75% __walk_page_range
+ 9.70% show_map_vma.isra.23
0.61% seq_puts
== After patch ==
- 75.51% 4.62% python [kernel.kallsyms] [k] show_smap.isra.33
- 70.88% show_smap.isra.33
+ 24.82% seq_put_decimal_ull_w
+ 19.78% __walk_page_range
+ 12.74% seq_printf
+ 11.08% show_map_vma.isra.23
+ 1.68% seq_puts
[akpm@linux-foundation.org: fix drivers/of/unittest.c build]
Link: http://lkml.kernel.org/r/20180212074931.7227-1-avagin@openvz.org
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 3c8ba0d61d ("kernel.h: Retain constant expression output for
max()/min()") rewrote our min/max macros to be very clever, but in the
meantime resurrected a variable name shadow issue that we had had
previously fixed in commit 589a9785ee ("min/max: remove sparse
warnings when they're nested").
That commit talks about the sparse warnings that this shadowing causes,
which we ignored as just a minor annoyance. But it turns out that the
sparse warning is the least of our problems. We actually have a real
bug due to the shadowing through the interaction with "min_not_zero()",
which ends up doing
min(__x, __y)
internally, and then the new declaration of "__x" and "__y" as new
variables in __cmp_once() results in a complete mess of an expression,
and "min_not_zero()" doesn't work at all.
For some odd reason, this only ever caused (reported) problems on s390,
even though it is a generic issue and most of the (obviously successful)
testing of the problematic commit had happened on other architectures.
Quoting Sebastian Ott:
"What happened is that the bio build by the partition detection code
was attempted to be split by the block layer because the block queue
had a max_sector setting of 0. blk_queue_max_hw_sectors uses
min_not_zero."
So re-introduce the use of __UNIQUE_ID() to make sure that the min/max
macros do not have these kinds of clashes.
[ That said, __UNIQUE_ID() itself has several issues that make it less
than wonderful.
In particular, the "uniqueness" has a fallback on the line number,
which means that it's not actually unique in more complex cases if you
don't build with gcc or clang (which have working unique counters that
aren't tied to line numbers).
That historical broken fallback also means that we have that pointless
"prefix" argument that doesn't actually make much sense _except_ for
the known-broken case. Oh well. ]
Fixes: 3c8ba0d61d ("kernel.h: Retain constant expression output for max()/min()")
Reported-and-tested-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In the effort to remove all VLAs from the kernel[1], it is desirable to
build with -Wvla. However, this warning is overly pessimistic, in that
it is only happy with stack array sizes that are declared as constant
expressions, and not constant values. One case of this is the
evaluation of the max() macro which, due to its construction, ends up
converting constant expression arguments into a constant value result.
All attempts to rewrite this macro with __builtin_constant_p() failed
with older compilers (e.g. gcc 4.4)[2]. However, Martin Uecker,
constructed[3] a mind-shattering solution that works everywhere.
Cthulhu fhtagn!
This patch updates the min()/max() macros to evaluate to a constant
expression when called on constant expression arguments. This removes
several false-positive stack VLA warnings from an x86 allmodconfig build
when -Wvla is added:
$ diff -u before.txt after.txt | grep ^-
-drivers/input/touchscreen/cyttsp4_core.c:871:2: warning: ISO C90 forbids variable length array ‘ids’ [-Wvla]
-fs/btrfs/tree-checker.c:344:4: warning: ISO C90 forbids variable length array ‘namebuf’ [-Wvla]
-lib/vsprintf.c:747:2: warning: ISO C90 forbids variable length array ‘sym’ [-Wvla]
-net/ipv4/proc.c:403:2: warning: ISO C90 forbids variable length array ‘buff’ [-Wvla]
-net/ipv6/proc.c:198:2: warning: ISO C90 forbids variable length array ‘buff’ [-Wvla]
-net/ipv6/proc.c:218:2: warning: ISO C90 forbids variable length array ‘buff64’ [-Wvla]
This also updates two cases where different enums were being compared
and explicitly casts them to int (which matches the old side-effect of
the single-evaluation code): one in tpm/tpm_tis_core.h, and one in
drm/drm_color_mgmt.c.
[1] https://lkml.org/lkml/2018/3/7/621
[2] https://lkml.org/lkml/2018/3/10/170
[3] https://lkml.org/lkml/2018/3/20/845
Co-Developed-by: Linus Torvalds <torvalds@linux-foundation.org>
Co-Developed-by: Martin Uecker <Martin.Uecker@med.uni-goettingen.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Here is the big set of Staging/IIO driver patches for 4.17-rc1.
It is a lot, over 500 changes, but not huge by previous kernel release
standards. We deleted more lines than we added again (27k added vs. 91k
remvoed), thanks to finally being able to delete the IRDA drivers and
networking code.
We also deleted the ccree crypto driver, but that's coming back in
through the crypto tree to you, in a much cleaned-up form.
Added this round is at lot of "mt7621" device support, which is for an
embedded device that Neil Brown cares about, and of course a handful of
new IIO drivers as well.
And finally, the fsl-mc core code moved out of the staging tree to the
"real" part of the kernel, which is nice to see happen as well.
Full details are in the shortlog, which has all of the tiny cleanup
patches described.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging/IIO updates from Greg KH:
"Here is the big set of Staging/IIO driver patches for 4.17-rc1.
It is a lot, over 500 changes, but not huge by previous kernel release
standards. We deleted more lines than we added again (27k added vs.
91k remvoed), thanks to finally being able to delete the IRDA drivers
and networking code.
We also deleted the ccree crypto driver, but that's coming back in
through the crypto tree to you, in a much cleaned-up form.
Added this round is at lot of "mt7621" device support, which is for an
embedded device that Neil Brown cares about, and of course a handful
of new IIO drivers as well.
And finally, the fsl-mc core code moved out of the staging tree to the
"real" part of the kernel, which is nice to see happen as well.
Full details are in the shortlog, which has all of the tiny cleanup
patches described.
All of these have been in linux-next for a while with no reported
issues"
* tag 'staging-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (579 commits)
staging: rtl8723bs: Remove yield call, replace with cond_resched()
staging: rtl8723bs: Replace yield() call with cond_resched()
staging: rtl8723bs: Remove unecessary newlines from 'odm.h'.
staging: rtl8723bs: Rework 'struct _ODM_Phy_Status_Info_' coding style.
staging: rtl8723bs: Rework 'struct _ODM_Per_Pkt_Info_' coding style.
staging: rtl8723bs: Replace NULL pointer comparison with '!'.
staging: rtl8723bs: Factor out rtl8723bs_recv_tasklet() sections.
staging: rtl8723bs: Fix function signature that goes over 80 characters.
staging: rtl8723bs: Fix lines too long in update_recvframe_attrib().
staging: rtl8723bs: Remove unnecessary blank lines in 'rtl8723bs_recv.c'.
staging: rtl8723bs: Change camel case to snake case in 'rtl8723bs_recv.c'.
staging: rtl8723bs: Add missing braces in else statement.
staging: rtl8723bs: Add spaces around ternary operators.
staging: rtl8723bs: Fix lines with trailing open parentheses.
staging: rtl8723bs: Remove unnecessary length #define's.
staging: rtl8723bs: Fix IEEE80211 authentication algorithm constants.
staging: rtl8723bs: Fix alignment in rtw_wx_set_auth().
staging: rtl8723bs: Remove braces from single statement conditionals.
staging: rtl8723bs: Remove unecessary braces from switch statement.
staging: rtl8723bs: Fix newlines in rtw_wx_set_auth().
...
move COUNT_ARGS() macro from apparmor to generic header and extend it
to count till twelve.
COUNT() was an alternative name for this logic, but it's used for
different purpose in many other places.
Similarly for CONCATENATE() macro.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Convert init_kernel_text() to a global function and use it in a few
places instead of manually comparing _sinittext and _einittext.
Note that kallsyms.h has a very similar function called
is_kernel_inittext(), but its end check is inclusive. I'm not sure
whether that's intentional behavior, so I didn't touch it.
Suggested-by: Jason Baron <jbaron@akamai.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/4335d02be8d45ca7d265d2f174251d0b7ee6c5fd.1519051220.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There is no option to perform 64bit integer sqrt on 32bit platform.
Added stronger typed int_sqrt64 enables the 64bit calculations to
be performed on 32bit platforms. Using same algorithm as int_sqrt()
with strong typing provides enough precision also on 32bit platforms,
but it sacrifices some performance. In case values are smaller than
ULONG_MAX the standard int_sqrt is used for calculation to maximize the
performance due to more native calculations.
Signed-off-by: Crt Mori <cmo@melexis.com>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This is the gist of a patch which we've been forward-porting in our
kernels for a long time now and it probably would make a good sense to
have such TAINT_AUX flag upstream which can be used by each distro etc,
how they see fit. This way, we won't need to forward-port a distro-only
version indefinitely.
Add an auxiliary taint flag to be used by distros and others. This
obviates the need to forward-port whatever internal solutions people
have in favor of a single flag which they can map arbitrarily to a
definition of their pleasing.
The "X" mnemonic could also mean eXternal, which would be taint from a
distro or something else but not the upstream kernel. We will use it to
mark modules for which we don't provide support. I.e., a really
eXternal module.
Link: http://lkml.kernel.org/r/20170911134533.dp5mtyku5bongx4c@pd.tnic
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add kernel-doc notation for some macros. Correct kernel-doc comments &
typos for a few macros.
Link: http://lkml.kernel.org/r/76fa1403-1511-be4c-e9c4-456b43edfad3@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This macro is useful to avoid link error on 32-bit systems.
We have the same definition in two drivers, so move it to
include/linux/kernel.h
While we are here, refactor DIV_ROUND_UP_ULL() by using
DIV_ROUND_DOWN_ULL().
Link: http://lkml.kernel.org/r/1500945156-12907-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Mark Brown <broonie@kernel.org>
Cc: Cyrille Pitchen <cyrille.pitchen@wedev4u.fr>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Boris Brezillon <boris.brezillon@free-electrons.com>
Cc: Marek Vasut <marek.vasut@gmail.com>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This implements refcount_t overflow protection on x86 without a noticeable
performance impact, though without the fuller checking of REFCOUNT_FULL.
This is done by duplicating the existing atomic_t refcount implementation
but with normally a single instruction added to detect if the refcount
has gone negative (e.g. wrapped past INT_MAX or below zero). When detected,
the handler saturates the refcount_t to INT_MIN / 2. With this overflow
protection, the erroneous reference release that would follow a wrap back
to zero is blocked from happening, avoiding the class of refcount-overflow
use-after-free vulnerabilities entirely.
Only the overflow case of refcounting can be perfectly protected, since
it can be detected and stopped before the reference is freed and left to
be abused by an attacker. There isn't a way to block early decrements,
and while REFCOUNT_FULL stops increment-from-zero cases (which would
be the state _after_ an early decrement and stops potential double-free
conditions), this fast implementation does not, since it would require
the more expensive cmpxchg loops. Since the overflow case is much more
common (e.g. missing a "put" during an error path), this protection
provides real-world protection. For example, the two public refcount
overflow use-after-free exploits published in 2016 would have been
rendered unexploitable:
http://perception-point.io/2016/01/14/analysis-and-exploitation-of-a-linux-kernel-vulnerability-cve-2016-0728/http://cyseclabs.com/page?n=02012016
This implementation does, however, notice an unchecked decrement to zero
(i.e. caller used refcount_dec() instead of refcount_dec_and_test() and it
resulted in a zero). Decrements under zero are noticed (since they will
have resulted in a negative value), though this only indicates that a
use-after-free may have already happened. Such notifications are likely
avoidable by an attacker that has already exploited a use-after-free
vulnerability, but it's better to have them reported than allow such
conditions to remain universally silent.
On first overflow detection, the refcount value is reset to INT_MIN / 2
(which serves as a saturation value) and a report and stack trace are
produced. When operations detect only negative value results (such as
changing an already saturated value), saturation still happens but no
notification is performed (since the value was already saturated).
On the matter of races, since the entire range beyond INT_MAX but before
0 is negative, every operation at INT_MIN / 2 will trap, leaving no
overflow-only race condition.
As for performance, this implementation adds a single "js" instruction
to the regular execution flow of a copy of the standard atomic_t refcount
operations. (The non-"and_test" refcount_dec() function, which is uncommon
in regular refcount design patterns, has an additional "jz" instruction
to detect reaching exactly zero.) Since this is a forward jump, it is by
default the non-predicted path, which will be reinforced by dynamic branch
prediction. The result is this protection having virtually no measurable
change in performance over standard atomic_t operations. The error path,
located in .text.unlikely, saves the refcount location and then uses UD0
to fire a refcount exception handler, which resets the refcount, handles
reporting, and returns to regular execution. This keeps the changes to
.text size minimal, avoiding return jumps and open-coded calls to the
error reporting routine.
Example assembly comparison:
refcount_inc() before:
.text:
ffffffff81546149: f0 ff 45 f4 lock incl -0xc(%rbp)
refcount_inc() after:
.text:
ffffffff81546149: f0 ff 45 f4 lock incl -0xc(%rbp)
ffffffff8154614d: 0f 88 80 d5 17 00 js ffffffff816c36d3
...
.text.unlikely:
ffffffff816c36d3: 48 8d 4d f4 lea -0xc(%rbp),%rcx
ffffffff816c36d7: 0f ff (bad)
These are the cycle counts comparing a loop of refcount_inc() from 1
to INT_MAX and back down to 0 (via refcount_dec_and_test()), between
unprotected refcount_t (atomic_t), fully protected REFCOUNT_FULL
(refcount_t-full), and this overflow-protected refcount (refcount_t-fast):
2147483646 refcount_inc()s and 2147483647 refcount_dec_and_test()s:
cycles protections
atomic_t 82249267387 none
refcount_t-fast 82211446892 overflow, untested dec-to-zero
refcount_t-full 144814735193 overflow, untested dec-to-zero, inc-from-zero
This code is a modified version of the x86 PAX_REFCOUNT atomic_t
overflow defense from the last public patch of PaX/grsecurity, based
on my understanding of the code. Changes or omissions from the original
code are mine and don't reflect the original grsecurity/PaX code. Thanks
to PaX Team for various suggestions for improvement for repurposing this
code to be a refcount-only protection.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Hans Liljestrand <ishkamiel@gmail.com>
Cc: James Bottomley <James.Bottomley@hansenpartnership.com>
Cc: Jann Horn <jannh@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Serge E. Hallyn <serge@hallyn.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: arozansk@redhat.com
Cc: axboe@kernel.dk
Cc: kernel-hardening@lists.openwall.com
Cc: linux-arch <linux-arch@vger.kernel.org>
Link: http://lkml.kernel.org/r/20170815161924.GA133115@beast
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If the first parameter of container_of() is a pointer to a
non-const-qualified array type (and the third parameter names a
non-const-qualified array member), the local variable __mptr will be
defined with a const-qualified array type. In ISO C, these types are
incompatible. They work as expected in GNU C, but some versions will
issue warnings. For example, GCC 4.9 produces the warning
"initialization from incompatible pointer type".
Here is an example of where the problem occurs:
-------------------------------------------------------
#include <linux/kernel.h>
#include <linux/module.h>
MODULE_LICENSE("GPL");
struct st {
int a;
char b[16];
};
static int __init example_init(void) {
struct st t = { .a = 101, .b = "hello" };
char (*p)[16] = &t.b;
struct st *x = container_of(p, struct st, b);
printk(KERN_DEBUG "%p %p\n", (void *)&t, (void *)x);
return 0;
}
static void __exit example_exit(void) {
}
module_init(example_init);
module_exit(example_exit);
-------------------------------------------------------
Building the module with gcc-4.9 results in these warnings (where '{m}'
is the module source and '{k}' is the kernel source):
-------------------------------------------------------
In file included from {m}/example.c:1:0:
{m}/example.c: In function `example_init':
{k}/include/linux/kernel.h:854:48: warning: initialization from incompatible pointer type
const typeof( ((type *)0)->member ) *__mptr = (ptr); \
^
{m}/example.c:14:17: note: in expansion of macro `container_of'
struct st *x = container_of(p, struct st, b);
^
{k}/include/linux/kernel.h:854:48: warning: (near initialization for `x')
const typeof( ((type *)0)->member ) *__mptr = (ptr); \
^
{m}/example.c:14:17: note: in expansion of macro `container_of'
struct st *x = container_of(p, struct st, b);
^
-------------------------------------------------------
Replace the type checking performed by the macro to avoid these
warnings. Make sure `*(ptr)` either has type compatible with the
member, or has type compatible with `void`, ignoring qualifiers. Raise
compiler errors if this is not true. This is stronger than the previous
behaviour, which only resulted in compiler warnings for a type mismatch.
[arnd@arndb.de: fix new warnings for container_of()]
Link: http://lkml.kernel.org/r/20170620200940.90557-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/20170525120316.24473-7-abbotti@mev.co.uk
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Johannes Berg <johannes.berg@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
might_sleep() debugging and smp_processor_id() debugging should be active
right after the scheduler starts working. The init task can invoke
smp_processor_id() from preemptible context as it is pinned on the boot cpu
until sched_smp_init() removes the pinning and lets it schedule on all non
isolated cpus.
Add a new state which allows to enable those checks earlier and add it to
the xen do_poweroff() function.
No functional change.
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170516184736.196214622@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull crypto updates from Herbert Xu:
"Here is the crypto update for 4.12:
API:
- Add batch registration for acomp/scomp
- Change acomp testing to non-unique compressed result
- Extend algorithm name limit to 128 bytes
- Require setkey before accept(2) in algif_aead
Algorithms:
- Add support for deflate rfc1950 (zlib)
Drivers:
- Add accelerated crct10dif for powerpc
- Add crc32 in stm32
- Add sha384/sha512 in ccp
- Add 3des/gcm(aes) for v5 devices in ccp
- Add Queue Interface (QI) backend support in caam
- Add new Exynos RNG driver
- Add ThunderX ZIP driver
- Add driver for hardware random generator on MT7623 SoC"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (101 commits)
crypto: stm32 - Fix OF module alias information
crypto: algif_aead - Require setkey before accept(2)
crypto: scomp - add support for deflate rfc1950 (zlib)
crypto: scomp - allow registration of multiple scomps
crypto: ccp - Change ISR handler method for a v5 CCP
crypto: ccp - Change ISR handler method for a v3 CCP
crypto: crypto4xx - rename ce_ring_contol to ce_ring_control
crypto: testmgr - Allow ecb(cipher_null) in FIPS mode
Revert "crypto: arm64/sha - Add constant operand modifier to ASM_EXPORT"
crypto: ccp - Disable interrupts early on unload
crypto: ccp - Use only the relevant interrupt bits
hwrng: mtk - Add driver for hardware random generator on MT7623 SoC
dt-bindings: hwrng: Add Mediatek hardware random generator bindings
crypto: crct10dif-vpmsum - Fix missing preempt_disable()
crypto: testmgr - replace compression known answer test
crypto: acomp - allow registration of multiple acomps
hwrng: n2 - Use devm_kcalloc() in n2rng_probe()
crypto: chcr - Fix error handling related to 'chcr_alloc_shash'
padata: get_next is never NULL
crypto: exynos - Add new Exynos RNG driver
...
Few parts of kernel define their own macro for aligning down so provide
a common define for this, with the same usage and assumptions as existing
ALIGN.
Convert also three existing implementations to this one.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
While working on a thermal driver I encounter a scenario where the
divisor could be negative, instead of adding local code to handle this I
though I first try to add support for this in DIV_ROUND_CLOSEST.
Add support to DIV_ROUND_CLOSEST for negative divisors if both dividend
and divisor variable types are signed. This should not alter current
behavior for users of the macro as previously negative divisors where
not supported.
Before:
DIV_ROUND_CLOSEST( 59, 4) = 15
DIV_ROUND_CLOSEST( 59, -4) = -14
DIV_ROUND_CLOSEST( -59, 4) = -15
DIV_ROUND_CLOSEST( -59, -4) = 14
After:
DIV_ROUND_CLOSEST( 59, 4) = 15
DIV_ROUND_CLOSEST( 59, -4) = -15
DIV_ROUND_CLOSEST( -59, 4) = -15
DIV_ROUND_CLOSEST( -59, -4) = 15
[akpm@linux-foundation.org: fix comment, per Guenter]
Link: http://lkml.kernel.org/r/20161222102217.29011-1-niklas.soderlund+renesas@ragnatech.se
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 7fd8329ba5 ("taint/module: Clean up global and module taint
flags handling") used the key words true and false as character members
of a new struct. These names cause problems when out-of-kernel modules
such as VirtualBox include their own definitions of true and false.
Fixes: 7fd8329ba5 ("taint/module: Clean up global and module taint flags handling")
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Reported-by: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jessica Yu <jeyu@redhat.com>
Summary of modules changes for the 4.10 merge window:
* The rodata= cmdline parameter has been extended to additionally
apply to module mappings
* Fix a hard to hit race between module loader error/clean up
handling and ftrace registration
* Some code cleanups, notably panic.c and modules code use a
unified taint_flags table now. This is much cleaner than
duplicating the taint flag code in modules.c
Signed-off-by: Jessica Yu <jeyu@redhat.com>
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Merge tag 'modules-for-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull modules updates from Jessica Yu:
"Summary of modules changes for the 4.10 merge window:
- The rodata= cmdline parameter has been extended to additionally
apply to module mappings
- Fix a hard to hit race between module loader error/clean up
handling and ftrace registration
- Some code cleanups, notably panic.c and modules code use a unified
taint_flags table now. This is much cleaner than duplicating the
taint flag code in modules.c"
* tag 'modules-for-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
module: fix DEBUG_SET_MODULE_RONX typo
module: extend 'rodata=off' boot cmdline parameter to module mappings
module: Fix a comment above strong_try_module_get()
module: When modifying a module's text ignore modules which are going away too
module: Ensure a module's state is set accordingly during module coming cleanup code
module: remove trailing whitespace
taint/module: Clean up global and module taint flags handling
modpost: free allocated memory
Pull percpu update from Tejun Heo:
"This includes just one patch to reject non-power-of-2 alignments and
trigger warning. Interestingly, this actually caught a bug in XEN
ARM64"
* 'for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
percpu: ensure the requested alignment is power of two
The commit 66cc69e34e ("Fix: module signature vs tracepoints:
add new TAINT_UNSIGNED_MODULE") updated module_taint_flags() to
potentially print one more character. But it did not increase the
size of the corresponding buffers in m_show() and print_modules().
We have recently done the same mistake when adding a taint flag
for livepatching, see
https://lkml.kernel.org/r/cfba2c823bb984690b73572aaae1db596b54a082.1472137475.git.jpoimboe@redhat.com
Also struct module uses an incompatible type for mod-taints flags.
It survived from the commit 2bc2d61a96 ("[PATCH] list module
taint flags in Oops/panic"). There was used "int" for the global taint
flags at these times. But only the global tain flags was later changed
to "unsigned long" by the commit 25ddbb18aa ("Make the taint
flags reliable").
This patch defines TAINT_FLAGS_COUNT that can be used to create
arrays and buffers of the right size. Note that we could not use
enum because the taint flag indexes are used also in assembly code.
Then it reworks the table that describes the taint flags. The TAINT_*
numbers can be used as the index. Instead, we add information
if the taint flag is also shown per-module.
Finally, it uses "unsigned long", bit operations, and the updated
taint_flags table also for mod->taints.
It is not optimal because only few taint flags can be printed by
module_taint_flags(). But better be on the safe side. IMHO, it is
not worth the optimization and this is a good compromise.
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: http://lkml.kernel.org/r/1474458442-21581-1-git-send-email-pmladek@suse.com
[jeyu@redhat.com: fix broken lkml link in changelog]
Signed-off-by: Jessica Yu <jeyu@redhat.com>
Move READ and WRITE to kernel.h and don't define them in terms of block
layer ops; they are our generic data direction indicators these days
and have no more resemblance with the block layer ops.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
The percpu allocator expectedly assumes that the requested alignment
is power of two but hasn't been veryfing the input. If the specified
alignment isn't power of two, the allocator can malfunction. Add the
sanity check.
The following is detailed analysis of the effects of alignments which
aren't power of two.
The alignment must be a even at least since the LSB of a chunk->map
element is used as free/in-use flag of a area; besides, the alignment
must be a power of 2 too since ALIGN() doesn't work well for other
alignment always but is adopted by pcpu_fit_in_area(). IOW, the
current allocator only works well for a power of 2 aligned area
allocation.
See below opposite example for why an odd alignment doesn't work.
Let's assume area [16, 36) is free but its previous one is in-use, we
want to allocate a @size == 8 and @align == 7 area. The larger area
[16, 36) is split to three areas [16, 21), [21, 29), [29, 36)
eventually. However, due to the usage for a chunk->map element, the
actual offset of the aim area [21, 29) is 21 but is recorded in
relevant element as 20; moreover, the residual tail free area [29,
36) is mistook as in-use and is lost silently
Unlike macro roundup(), ALIGN(x, a) doesn't work if @a isn't a power
of 2 for example, roundup(10, 6) == 12 but ALIGN(10, 6) == 10, and
the latter result isn't desired obviously.
tj: Code style and patch description updates.
Signed-off-by: zijun_hu <zijun_hu@htc.com>
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Currently, when min/max are nested within themselves, sparse will warn:
warning: symbol '_min1' shadows an earlier one
originally declared here
warning: symbol '_min1' shadows an earlier one
originally declared here
warning: symbol '_min2' shadows an earlier one
originally declared here
This also immediately happens when min3() or max3() are used.
Since sparse implements __COUNTER__, we can use __UNIQUE_ID() to
generate unique variable names, avoiding this.
Link: http://lkml.kernel.org/r/1471519773-29882-1-git-send-email-johannes@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Oleg noted that by making do_exit() use __schedule() for the TASK_DEAD
context switch, we can avoid the TASK_DEAD special case currently in
__schedule() because that avoids the extra preempt_disable() from
schedule().
In order to facilitate this, create a do_task_dead() helper which we
place in the scheduler code, such that it can access __schedule().
Also add some __noreturn annotations to the functions, there's no
coming back from do_exit().
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Cheng Chao <cs.os.kernel@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akpm@linux-foundation.org
Cc: chris@chris-wilson.co.uk
Cc: tj@kernel.org
Link: http://lkml.kernel.org/r/20160913163729.GB5012@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
kernel.h header doesn't directly use dynamic debug, instead we can
include it in module.c (which used it via kernel.h). printk.h only uses
it if CONFIG_DYNAMIC_DEBUG is on, changing the inclusion to only happen
in that case.
Link: http://lkml.kernel.org/r/1468429793-16917-1-git-send-email-luisbg@osg.samsung.com
[luisbg@osg.samsung.com: include dynamic_debug.h in drb_int.h]
Link: http://lkml.kernel.org/r/1468447828-18558-2-git-send-email-luisbg@osg.samsung.com
Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It is not always easy to determine the cause of an RCU stall just by
analysing the RCU stall messages, mainly when the problem is caused
by the indirect starvation of rcu threads. For example, when preempt_rcu
is not awakened due to the starvation of a timer softirq.
We have been hard coding panic() in the RCU stall functions for
some time while testing the kernel-rt. But this is not possible in
some scenarios, like when supporting customers.
This patch implements the sysctl kernel.panic_on_rcu_stall. If
set to 1, the system will panic() when an RCU stall takes place,
enabling the capture of a vmcore. The vmcore provides a way to analyze
all kernel/tasks states, helping out to point to the culprit and the
solution for the stall.
The kernel.panic_on_rcu_stall sysctl is disabled by default.
Changes from v1:
- Fixed a typo in the git log
- The if(sysctl_panic_on_rcu_stall) panic() is in a static function
- Fixed the CONFIG_TINY_RCU compilation issue
- The var sysctl_panic_on_rcu_stall is now __read_mostly
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Reviewed-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Tested-by: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Here's the big staging and iio driver update for 4.7-rc1.
I think we almost broke even with this release, only adding a few more
lines than we removed, which isn't bad overall given that there's a
bunch of new iio drivers added. The Lustre developers seem to have
woken up from their sleep and have been doing a great job in cleaning up
the code and pruning unused or old cruft, the filesystem is almost
readable :)
Other than that, just a lot of basic coding style cleanups in the churn.
All have been in linux-next for a while with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging and IIO driver updates from Greg KH:
"Here's the big staging and iio driver update for 4.7-rc1.
I think we almost broke even with this release, only adding a few more
lines than we removed, which isn't bad overall given that there's a
bunch of new iio drivers added.
The Lustre developers seem to have woken up from their sleep and have
been doing a great job in cleaning up the code and pruning unused or
old cruft, the filesystem is almost readable :)
Other than that, just a lot of basic coding style cleanups in the
churn. All have been in linux-next for a while with no reported
issues"
* tag 'staging-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (938 commits)
Staging: emxx_udc: emxx_udc: fixed coding style issue
staging/gdm724x: fix "alignment should match open parenthesis" issues
staging/gdm724x: Fix avoid CamelCase
staging: unisys: rename misleading var ii with frag
staging: unisys: visorhba: switch success handling to error handling
staging: unisys: visorhba: main path needs to flow down the left margin
staging: unisys: visorinput: handle_locking_key() simplifications
staging: unisys: visorhba: fail gracefully for thread creation failures
staging: unisys: visornic: comment restructuring and removing bad diction
staging: unisys: fix format string %Lx to %llx for u64
staging: unisys: remove unused struct members
staging: unisys: visorchannel: correct variable misspelling
staging: unisys: visorhba: replace functionlike macro with function
staging: dgnc: Need to check for NULL of ch
staging: dgnc: remove redundant condition check
staging: dgnc: fix 'line over 80 characters'
staging: dgnc: clean up the dgnc_get_modem_info()
staging: lustre: lnet: enable configuration per NI interface
staging: lustre: o2iblnd: properly set ibr_why
staging: lustre: o2iblnd: remove last of kiblnd_tunables_fini
...
Attach the malloc attribute to a few allocation functions. This helps
gcc generate better code by telling it that the return value doesn't
alias any existing pointers (which is even more valuable given the
pessimizations implied by -fno-strict-aliasing).
A simple example of what this allows gcc to do can be seen by looking at
the last part of drm_atomic_helper_plane_reset:
plane->state = kzalloc(sizeof(*plane->state), GFP_KERNEL);
if (plane->state) {
plane->state->plane = plane;
plane->state->rotation = BIT(DRM_ROTATE_0);
}
which compiles to
e8 99 bf d6 ff callq ffffffff8116d540 <kmem_cache_alloc_trace>
48 85 c0 test %rax,%rax
48 89 83 40 02 00 00 mov %rax,0x240(%rbx)
74 11 je ffffffff814015c4 <drm_atomic_helper_plane_reset+0x64>
48 89 18 mov %rbx,(%rax)
48 8b 83 40 02 00 00 mov 0x240(%rbx),%rax [*]
c7 40 40 01 00 00 00 movl $0x1,0x40(%rax)
With this patch applied, the instruction at [*] is elided, since the
store to plane->state->plane is known to not alter the value of
plane->state.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This function had copies in 3 different files. Unify them in kernel.h.
Cc: Joe Perches <joe@perches.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Rob Clark <robdclark@gmail.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Acked-by: Daniel Vetter <daniel.vetter@intel.com> [drm/i915/]
Acked-by: Rob Clark <robdclark@gmail.com> [drm/msm/]
Acked-by: Lucas Stach <l.stach@pengutronix.de> [drm/etinav/]
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some visible changes:
A new flag was added to distinguish traces done in NMI context.
Preempt tracer now shows functions where preemption is disabled but
interrupts are still enabled.
Other notes:
Updates were done to function tracing to allow better performance
with perf.
Infrastructure code has been added to allow for a new histogram
feature for recording live trace event histograms that can be
configured by simple user commands. The feature itself was just
finished, but needs a round in linux-next before being pulled.
This only includes some infrastructure changes that will be needed.
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Merge tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
"Nothing major this round. Mostly small clean ups and fixes.
Some visible changes:
- A new flag was added to distinguish traces done in NMI context.
- Preempt tracer now shows functions where preemption is disabled but
interrupts are still enabled.
Other notes:
- Updates were done to function tracing to allow better performance
with perf.
- Infrastructure code has been added to allow for a new histogram
feature for recording live trace event histograms that can be
configured by simple user commands. The feature itself was just
finished, but needs a round in linux-next before being pulled.
This only includes some infrastructure changes that will be needed"
* tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (22 commits)
tracing: Record and show NMI state
tracing: Fix trace_printk() to print when not using bprintk()
tracing: Remove redundant reset per-CPU buff in irqsoff tracer
x86: ftrace: Fix the misleading comment for arch/x86/kernel/ftrace.c
tracing: Fix crash from reading trace_pipe with sendfile
tracing: Have preempt(irqs)off trace preempt disabled functions
tracing: Fix return while holding a lock in register_tracer()
ftrace: Use kasprintf() in ftrace_profile_tracefs()
ftrace: Update dynamic ftrace calls only if necessary
ftrace: Make ftrace_hash_rec_enable return update bool
tracing: Fix typoes in code comment and printk in trace_nop.c
tracing, writeback: Replace cgroup path to cgroup ino
tracing: Use flags instead of bool in trigger structure
tracing: Add an unreg_all() callback to trigger commands
tracing: Add needs_rec flag to event triggers
tracing: Add a per-event-trigger 'paused' field
tracing: Add get_syscall_name()
tracing: Add event record param to trigger_ops.func()
tracing: Make event trigger functions available
tracing: Make ftrace_event_field checking functions available
...
Commit 1717f2096b ("panic, x86: Fix re-entrance problem due to panic
on NMI") and commit 58c5661f21 ("panic, x86: Allow CPUs to save
registers even if looping in NMI context") introduced nmi_panic() which
prevents concurrent/recursive execution of panic(). It also saves
registers for the crash dump on x86.
However, there are some cases where NMI handlers still use panic().
This patch set partially replaces them with nmi_panic() in those cases.
Even this patchset is applied, some NMI or similar handlers (e.g. MCE
handler) continue to use panic(). This is because I can't test them
well and actual problems won't happen. For example, the possibility
that normal panic and panic on MCE happen simultaneously is very low.
This patch (of 3):
Convert nmi_panic() to a proper function and export it instead of
exporting internal implementation details to modules, for obvious
reasons.
Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Javi Merino <javi.merino@arm.com>
Cc: Gobinda Charan Maji <gobinda.cemk07@gmail.com>
Cc: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The trace_printk() code will allocate extra buffers if the compile detects
that a trace_printk() is used. To do this, the format of the trace_printk()
is saved to the __trace_printk_fmt section, and if that section is bigger
than zero, the buffers are allocated (along with a message that this has
happened).
If trace_printk() uses a format that is not a constant, and thus something
not guaranteed to be around when the print happens, the compiler optimizes
the fmt out, as it is not used, and the __trace_printk_fmt section is not
filled. This means the kernel will not allocate the special buffers needed
for the trace_printk() and the trace_printk() will not write anything to the
tracing buffer.
Adding a "__used" to the variable in the __trace_printk_fmt section will
keep it around, even though it is set to NULL. This will keep the string
from being printed in the debugfs/tracing/printk_formats section as it is
not needed.
Reported-by: Vlastimil Babka <vbabka@suse.cz>
Fixes: 07d777fe8c "tracing: Add percpu buffers for trace_printk()"
Cc: stable@vger.kernel.org # v3.5+
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Pull networking updates from David Miller:
"Highlights:
1) Support more Realtek wireless chips, from Jes Sorenson.
2) New BPF types for per-cpu hash and arrap maps, from Alexei
Starovoitov.
3) Make several TCP sysctls per-namespace, from Nikolay Borisov.
4) Allow the use of SO_REUSEPORT in order to do per-thread processing
of incoming TCP/UDP connections. The muxing can be done using a
BPF program which hashes the incoming packet. From Craig Gallek.
5) Add a multiplexer for TCP streams, to provide a messaged based
interface. BPF programs can be used to determine the message
boundaries. From Tom Herbert.
6) Add 802.1AE MACSEC support, from Sabrina Dubroca.
7) Avoid factorial complexity when taking down an inetdev interface
with lots of configured addresses. We were doing things like
traversing the entire address less for each address removed, and
flushing the entire netfilter conntrack table for every address as
well.
8) Add and use SKB bulk free infrastructure, from Jesper Brouer.
9) Allow offloading u32 classifiers to hardware, and implement for
ixgbe, from John Fastabend.
10) Allow configuring IRQ coalescing parameters on a per-queue basis,
from Kan Liang.
11) Extend ethtool so that larger link mode masks can be supported.
From David Decotigny.
12) Introduce devlink, which can be used to configure port link types
(ethernet vs Infiniband, etc.), port splitting, and switch device
level attributes as a whole. From Jiri Pirko.
13) Hardware offload support for flower classifiers, from Amir Vadai.
14) Add "Local Checksum Offload". Basically, for a tunneled packet
the checksum of the outer header is 'constant' (because with the
checksum field filled into the inner protocol header, the payload
of the outer frame checksums to 'zero'), and we can take advantage
of that in various ways. From Edward Cree"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1548 commits)
bonding: fix bond_get_stats()
net: bcmgenet: fix dma api length mismatch
net/mlx4_core: Fix backward compatibility on VFs
phy: mdio-thunder: Fix some Kconfig typos
lan78xx: add ndo_get_stats64
lan78xx: handle statistics counter rollover
RDS: TCP: Remove unused constant
RDS: TCP: Add sysctl tunables for sndbuf/rcvbuf on rds-tcp socket
net: smc911x: convert pxa dma to dmaengine
team: remove duplicate set of flag IFF_MULTICAST
bonding: remove duplicate set of flag IFF_MULTICAST
net: fix a comment typo
ethernet: micrel: fix some error codes
ip_tunnels, bpf: define IP_TUNNEL_OPTS_MAX and use it
bpf, dst: add and use dst_tclassid helper
bpf: make skb->tc_classid also readable
net: mvneta: bm: clarify dependencies
cls_bpf: reset class and reuse major in da
ldmvsw: Checkpatch sunvnet.c and sunvnet_common.c
ldmvsw: Add ldmvsw.c driver code
...
Create the kstrtobool_from_user() helper and move strtobool() logic into
the new kstrtobool() (matching all the other kstrto* functions).
Provides an inline wrapper for existing strtobool() callers.
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Joe Perches <joe@perches.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Amitkumar Karwar <akarwar@marvell.com>
Cc: Nishant Sarmukadam <nishants@marvell.com>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: Steve French <sfrench@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
DIV_ROUND_UP is defined in linux/kernel.h only for the kernel.
When ethtool.h is included by a userland app, we got the following error:
include/linux/ethtool.h:1218:8: error: variably modified 'queue_mask' at file scope
__u32 queue_mask[DIV_ROUND_UP(MAX_NUM_QUEUE, 32)];
^
Let's add a common definition in uapi and use it everywhere.
Fixes: ac2c7ad0e5 ("net/ethtool: introduce a new ioctl for per queue setting")
CC: Kan Liang <kan.liang@intel.com>
Suggested-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rewrite abs() so that its return type does not depend on the
architecture and no unexpected type conversion happen inside of it. The
only conversion is from unsigned to signed type. char is left as a
return type but treated as a signed type regradless of it's actual
signedness.
With the old version, int arguments were promoted to long and depending
on architecture a long argument might result in s64 or long return type
(which may or may not be the same).
This came after some back and forth with Nicolas. The current macro has
different return type (for the same input type) depending on
architecture which might be midly iritating.
An alternative version would promote to int like so:
#define abs(x) __abs_choose_expr(x, long long, \
__abs_choose_expr(x, long, \
__builtin_choose_expr( \
sizeof(x) <= sizeof(int), \
({ int __x = (x); __x<0?-__x:__x; }), \
((void)0))))
I have no preference but imagine Linus might. :] Nicolas argument against
is that promoting to int causes iconsistent behaviour:
int main(void) {
unsigned short a = 0, b = 1, c = a - b;
unsigned short d = abs(a - b);
unsigned short e = abs(c);
printf("%u %u\n", d, e); // prints: 1 65535
}
Then again, no sane person expects consistent behaviour from C integer
arithmetic. ;)
Note:
__builtin_types_compatible_p(unsigned char, char) is always false, and
__builtin_types_compatible_p(signed char, char) is also always false.
Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, kdump_nmi_shootdown_cpus(), a subroutine of crash_kexec(),
sends an NMI IPI to CPUs which haven't called panic() to stop them,
save their register information and do some cleanups for crash dumping.
However, if such a CPU is infinitely looping in NMI context, we fail to
save its register information into the crash dump.
For example, this can happen when unknown NMIs are broadcast to all
CPUs as follows:
CPU 0 CPU 1
=========================== ==========================
receive an unknown NMI
unknown_nmi_error()
panic() receive an unknown NMI
spin_trylock(&panic_lock) unknown_nmi_error()
crash_kexec() panic()
spin_trylock(&panic_lock)
panic_smp_self_stop()
infinite loop
kdump_nmi_shootdown_cpus()
issue NMI IPI -----------> blocked until IRET
infinite loop...
Here, since CPU 1 is in NMI context, the second NMI from CPU 0 is
blocked until CPU 1 executes IRET. However, CPU 1 never executes IRET,
so the NMI is not handled and the callback function to save registers is
never called.
In practice, this can happen on some servers which broadcast NMIs to all
CPUs when the NMI button is pushed.
To save registers in this case, we need to:
a) Return from NMI handler instead of looping infinitely
or
b) Call the callback function directly from the infinite loop
Inherently, a) is risky because NMI is also used to prevent corrupted
data from being propagated to devices. So, we chose b).
This patch does the following:
1. Move the infinite looping of CPUs which haven't called panic() in NMI
context (actually done by panic_smp_self_stop()) outside of panic() to
enable us to refer pt_regs. Please note that panic_smp_self_stop() is
still used for normal context.
2. Call a callback of kdump_nmi_shootdown_cpus() directly to save
registers and do some cleanups after setting waiting_for_crash_ipi which
is used for counting down the number of CPUs which handled the callback
Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Gobinda Charan Maji <gobinda.cemk07@gmail.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Javi Merino <javi.merino@arm.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: kexec@lists.infradead.org
Cc: linux-doc@vger.kernel.org
Cc: lkml <linux-kernel@vger.kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Stefan Lippers-Hollmann <s.l-h@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Link: http://lkml.kernel.org/r/20151210014628.25437.75256.stgit@softrs
[ Cleanup comments, fixup formatting. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
If panic on NMI happens just after panic() on the same CPU, panic() is
recursively called. Kernel stalls, as a result, after failing to acquire
panic_lock.
To avoid this problem, don't call panic() in NMI context if we've
already entered panic().
For that, introduce nmi_panic() macro to reduce code duplication. In
the case of panic on NMI, don't return from NMI handlers if another CPU
already panicked.
Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Gobinda Charan Maji <gobinda.cemk07@gmail.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Javi Merino <javi.merino@arm.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: kexec@lists.infradead.org
Cc: linux-doc@vger.kernel.org
Cc: lkml <linux-kernel@vger.kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/20151210014626.25437.13302.stgit@softrs
[ Cleanup comments, fixup formatting. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Switch everything to the new and more capable implementation of abs().
Mainly to give the new abs() a bit of a workout.
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For 64-bit arguments, the abs macro casts it to an int which leads to
lost precision and may cause incorrect results. To deal with 64-bit
types abs64 macro has been introduced but still there are places where
abs macro is used incorrectly.
To deal with the problem, expand abs macro such that it operates on s64
type when dealing with 64-bit types while still returning long when
dealing with smaller types.
This fixes one known bug (per John):
The internal clocksteering done for fine-grained error correction uses a
: logarithmic approximation, so any time adjtimex() adjusts the clock
: steering, timekeeping_freqadjust() quickly approximates the correct clock
: frequency over a series of ticks.
:
: Unfortunately, the logic in timekeeping_freqadjust(), introduced in commit
: dc491596f6 (Rework frequency adjustments to work better w/ nohz),
: used the abs() function with a s64 error value to calculate the size of
: the approximated adjustment to be made.
:
: Per include/linux/kernel.h: "abs() should not be used for 64-bit types
: (s64, u64, long long) - use abs64()".
:
: Thus on 32-bit platforms, this resulted in the clocksteering to take a
: quite dampended random walk trying to converge on the proper frequency,
: which caused the adjustments to be made much slower then intended (most
: easily observed when large adjustments are made).
Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Reported-by: John Stultz <john.stultz@linaro.org>
Tested-by: John Stultz <john.stultz@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds kvasprintf_const which tries to use kstrdup_const if possible:
If the format string contains no % characters, or if the format string is
exactly "%s", we delegate to kstrdup_const. Otherwise, we fall back to
kvasprintf.
Just as for kstrdup_const, the main motivation is to save memory by
reusing .rodata when possible.
The return value should be freed by kfree_const, just like for
kstrdup_const.
There is deliberately no kasprintf_const: In the vast majority of cases,
the format string argument is a literal, so one can determine statically
whether one could instead use kstrdup_const directly (which would also
require one to change all corresponding kfree calls to kfree_const).
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Using __printf attributes helps to detect several format string issues
at compile time (even though -Wformat-security is currently disabled in
Makefile). For example it can detect when formatting a pointer as a
number, like the issue fixed in commit a3fa71c40f ("wl18xx: show
rx_frames_per_rates as an array as it really is"), or when the arguments
do not match the format string, c.f. for example commit 5ce1aca814
("reiserfs: fix __RASSERT format string").
To prevent similar bugs in the future, add a __printf attribute to every
function prototype which needs one in include/linux/ and lib/. These
functions were mostly found by using gcc's -Wsuggest-attribute=format
flag.
Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge third patchbomb from Andrew Morton:
- the rest of MM
- scripts/gdb updates
- ipc/ updates
- lib/ updates
- MAINTAINERS updates
- various other misc things
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (67 commits)
genalloc: rename of_get_named_gen_pool() to of_gen_pool_get()
genalloc: rename dev_get_gen_pool() to gen_pool_get()
x86: opt into HAVE_COPY_THREAD_TLS, for both 32-bit and 64-bit
MAINTAINERS: add zpool
MAINTAINERS: BCACHE: Kent Overstreet has changed email address
MAINTAINERS: move Jens Osterkamp to CREDITS
MAINTAINERS: remove unused nbd.h pattern
MAINTAINERS: update brcm gpio filename pattern
MAINTAINERS: update brcm dts pattern
MAINTAINERS: update sound soc intel patterns
MAINTAINERS: remove website for paride
MAINTAINERS: update Emulex ocrdma email addresses
bcache: use kvfree() in various places
libcxgbi: use kvfree() in cxgbi_free_big_mem()
target: use kvfree() in session alloc and free
IB/ehca: use kvfree() in ipz_queue_{cd}tor()
drm/nouveau/gem: use kvfree() in u_free()
drm: use kvfree() in drm_free_large()
cxgb4: use kvfree() in t4_free_mem()
cxgb3: use kvfree() in cxgb_free_mem()
...
Main excitement here is Peter Zijlstra's lockless rbtree optimization to
speed module address lookup. He found some abusers of the module lock
doing that too.
A little bit of parameter work here too; including Dan Streetman's breaking
up the big param mutex so writing a parameter can load another module (yeah,
really). Unfortunately that broke the usual suspects, !CONFIG_MODULES and
!CONFIG_SYSFS, so those fixes were appended too.
Cheers,
Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull module updates from Rusty Russell:
"Main excitement here is Peter Zijlstra's lockless rbtree optimization
to speed module address lookup. He found some abusers of the module
lock doing that too.
A little bit of parameter work here too; including Dan Streetman's
breaking up the big param mutex so writing a parameter can load
another module (yeah, really). Unfortunately that broke the usual
suspects, !CONFIG_MODULES and !CONFIG_SYSFS, so those fixes were
appended too"
* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (26 commits)
modules: only use mod->param_lock if CONFIG_MODULES
param: fix module param locks when !CONFIG_SYSFS.
rcu: merge fix for Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE()
module: add per-module param_lock
module: make perm const
params: suppress unused variable error, warn once just in case code changes.
modules: clarify CONFIG_MODULE_COMPRESS help, suggest 'N'.
kernel/module.c: avoid ifdefs for sig_enforce declaration
kernel/workqueue.c: remove ifdefs over wq_power_efficient
kernel/params.c: export param_ops_bool_enable_only
kernel/params.c: generalize bool_enable_only
kernel/module.c: use generic module param operaters for sig_enforce
kernel/params: constify struct kernel_param_ops uses
sysfs: tightened sysfs permission checks
module: Rework module_addr_{min,max}
module: Use __module_address() for module_address_lookup()
module: Make the mod_tree stuff conditional on PERF_EVENTS || TRACING
module: Optimize __module_address() using a latched RB-tree
rbtree: Implement generic latch_tree
seqlock: Introduce raw_read_seqcount_latch()
...
Commit f06e5153f4 ("kernel/panic.c: add "crash_kexec_post_notifiers"
option for kdump after panic_notifers") introduced
"crash_kexec_post_notifiers" kernel boot option, which toggles wheather
panic() calls crash_kexec() before panic_notifiers and dump kmsg or after.
The problem is that the commit overlooks panic_on_oops kernel boot option.
If it is enabled, crash_kexec() is called directly without going through
panic() in oops path.
To fix this issue, this patch adds a check to "crash_kexec_post_notifiers"
in the condition of kexec_should_crash().
Also, put a comment in kexec_should_crash() to explain not obvious things
on this patch.
Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Acked-by: Baoquan He <bhe@redhat.com>
Tested-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
"monitonic raw". Also some enhancements to make the ring buffer even
faster. But the biggest and most noticeable change is the renaming of
the ftrace* files, structures and variables that have to deal with
trace events.
Over the years I've had several developers tell me about their confusion
with what ftrace is compared to events. Technically, "ftrace" is the
infrastructure to do the function hooks, which include tracing and also
helps with live kernel patching. But the trace events are a separate
entity altogether, and the files that affect the trace events should
not be named "ftrace". These include:
include/trace/ftrace.h -> include/trace/trace_events.h
include/linux/ftrace_event.h -> include/linux/trace_events.h
Also, functions that are specific for trace events have also been renamed:
ftrace_print_*() -> trace_print_*()
(un)register_ftrace_event() -> (un)register_trace_event()
ftrace_event_name() -> trace_event_name()
ftrace_trigger_soft_disabled()-> trace_trigger_soft_disabled()
ftrace_define_fields_##call() -> trace_define_fields_##call()
ftrace_get_offsets_##call() -> trace_get_offsets_##call()
Structures have been renamed:
ftrace_event_file -> trace_event_file
ftrace_event_{call,class} -> trace_event_{call,class}
ftrace_event_buffer -> trace_event_buffer
ftrace_subsystem_dir -> trace_subsystem_dir
ftrace_event_raw_##call -> trace_event_raw_##call
ftrace_event_data_offset_##call-> trace_event_data_offset_##call
ftrace_event_type_funcs_##call -> trace_event_type_funcs_##call
And a few various variables and flags have also been updated.
This has been sitting in linux-next for some time, and I have not heard
a single complaint about this rename breaking anything. Mostly because
these functions, variables and structures are mostly internal to the
tracing system and are seldom (if ever) used by anything external to that.
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Merge tag 'trace-v4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
"This patch series contains several clean ups and even a new trace
clock "monitonic raw". Also some enhancements to make the ring buffer
even faster. But the biggest and most noticeable change is the
renaming of the ftrace* files, structures and variables that have to
deal with trace events.
Over the years I've had several developers tell me about their
confusion with what ftrace is compared to events. Technically,
"ftrace" is the infrastructure to do the function hooks, which include
tracing and also helps with live kernel patching. But the trace
events are a separate entity altogether, and the files that affect the
trace events should not be named "ftrace". These include:
include/trace/ftrace.h -> include/trace/trace_events.h
include/linux/ftrace_event.h -> include/linux/trace_events.h
Also, functions that are specific for trace events have also been renamed:
ftrace_print_*() -> trace_print_*()
(un)register_ftrace_event() -> (un)register_trace_event()
ftrace_event_name() -> trace_event_name()
ftrace_trigger_soft_disabled() -> trace_trigger_soft_disabled()
ftrace_define_fields_##call() -> trace_define_fields_##call()
ftrace_get_offsets_##call() -> trace_get_offsets_##call()
Structures have been renamed:
ftrace_event_file -> trace_event_file
ftrace_event_{call,class} -> trace_event_{call,class}
ftrace_event_buffer -> trace_event_buffer
ftrace_subsystem_dir -> trace_subsystem_dir
ftrace_event_raw_##call -> trace_event_raw_##call
ftrace_event_data_offset_##call-> trace_event_data_offset_##call
ftrace_event_type_funcs_##call -> trace_event_type_funcs_##call
And a few various variables and flags have also been updated.
This has been sitting in linux-next for some time, and I have not
heard a single complaint about this rename breaking anything. Mostly
because these functions, variables and structures are mostly internal
to the tracing system and are seldom (if ever) used by anything
external to that"
* tag 'trace-v4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (33 commits)
ring_buffer: Allow to exit the ring buffer benchmark immediately
ring-buffer-benchmark: Fix the wrong type
ring-buffer-benchmark: Fix the wrong param in module_param
ring-buffer: Add enum names for the context levels
ring-buffer: Remove useless unused tracing_off_permanent()
ring-buffer: Give NMIs a chance to lock the reader_lock
ring-buffer: Add trace_recursive checks to ring_buffer_write()
ring-buffer: Allways do the trace_recursive checks
ring-buffer: Move recursive check to per_cpu descriptor
ring-buffer: Add unlikelys to make fast path the default
tracing: Rename ftrace_get_offsets_##call() to trace_event_get_offsets_##call()
tracing: Rename ftrace_define_fields_##call() to trace_event_define_fields_##call()
tracing: Rename ftrace_event_type_funcs_##call to trace_event_type_funcs_##call
tracing: Rename ftrace_data_offset_##call to trace_event_data_offset_##call
tracing: Rename ftrace_raw_##call event structures to trace_event_raw_##call
tracing: Rename ftrace_trigger_soft_disabled() to trace_trigger_soft_disabled()
tracing: Rename FTRACE_EVENT_FL_* flags to EVENT_FILE_FL_*
tracing: Rename struct ftrace_subsystem_dir to trace_subsystem_dir
tracing: Rename ftrace_event_name() to trace_event_name()
tracing: Rename FTRACE_MAX_EVENT to TRACE_EVENT_TYPE_MAX
...
The tracing_off_permanent() call is a way to disable all ring_buffers.
Nothing uses it and nothing should use it, as tracing_off() and
friends are better, as they disable the ring buffers related to
tracing. The tracing_off_permanent() even disabled non tracing
ring buffers. This is a bit drastic, and was added to handle NMIs
doing outputs that could corrupt the ring buffer when only tracing
used them. It is now obsolete and adds a little overhead, it should
be removed.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
There were some inconsistency in restriction to VERIFY_OCTAL_PERMISSIONS().
Previously the test was "User perms >= group perms >= other perms". The
permission field of User, Group or Other consists of three bits. LSB is
EXECUTE permission, MSB is READ permission and the middle bit is WRITE
permission. But logically WRITE is "more privileged" than READ.
Say for example, permission value is "0430". Here User has only READ
permission whereas Group has both WRITE and EXECUTE permission.
So, the checks could be tightened and the tests are separated to
USER_READABLE >= GROUP_READABLE >= OTHER_READABLE,
USER_WRITABLE >= GROUP_WRITABLE and OTHER_WRITABLE is not permitted.
Signed-off-by: Gobinda Charan Maji <gobinda.cemk07@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Commit 662bbcb274 ("mm, sched: Allow uaccess in atomic with
pagefault_disable()") removed might_sleep() checks for all user access
code (that uses might_fault()).
The reason was to disable wrong "sleep in atomic" warnings in the
following scenario:
pagefault_disable()
rc = copy_to_user(...)
pagefault_enable()
Which is valid, as pagefault_disable() increments the preempt counter
and therefore disables the pagefault handler. copy_to_user() will not
sleep and return an error code if a page is not available.
However, as all might_sleep() checks are removed,
CONFIG_DEBUG_ATOMIC_SLEEP would no longer detect the following scenario:
spin_lock(&lock);
rc = copy_to_user(...)
spin_unlock(&lock)
If the kernel is compiled with preemption turned on, preempt_disable()
will make in_atomic() detect disabled preemption. The fault handler would
correctly never sleep on user access.
However, with preemption turned off, preempt_disable() is usually a NOP
(with !CONFIG_PREEMPT_COUNT), therefore in_atomic() will not be able to
detect disabled preemption nor disabled pagefaults. The fault handler
could sleep.
We really want to enable CONFIG_DEBUG_ATOMIC_SLEEP checks for user access
functions again, otherwise we can end up with horrible deadlocks.
Root of all evil is that pagefault_disable() acts almost as
preempt_disable(), depending on preemption being turned on/off.
As we now have pagefault_disabled(), we can use it to distinguish
whether user acces functions might sleep.
Convert might_fault() into a makro that calls __might_fault(), to
allow proper file + line messages in case of a might_sleep() warning.
Reviewed-and-tested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: airlied@linux.ie
Cc: akpm@linux-foundation.org
Cc: benh@kernel.crashing.org
Cc: bigeasy@linutronix.de
Cc: borntraeger@de.ibm.com
Cc: daniel.vetter@intel.com
Cc: heiko.carstens@de.ibm.com
Cc: herbert@gondor.apana.org.au
Cc: hocko@suse.cz
Cc: hughd@google.com
Cc: mst@redhat.com
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: schwidefsky@de.ibm.com
Cc: yang.shi@windriver.com
Link: http://lkml.kernel.org/r/1431359540-32227-3-git-send-email-dahi@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We have grown a number of different implementations of
DIV_ROUND_CLOSEST_ULL throughout the kernel. Move the i915 one to
kernel.h so that it can be reused.
Signed-off-by: Javi Merino <javi.merino@arm.com>
Reviewed-by: Jeff Epler <jepler@unpythonic.net>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Guenter Roeck <linux@roeck-us.net>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Alex Elder <elder@linaro.org>
Cc: Antti Palosaari <crope@iki.fi>
Cc: Javi Merino <javi.merino@arm.com>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
__FUNCTION__ hasn't been treated as a string literal since gcc 3.4, so
this only helps people who only test-compile using 3.3 (compiler-gcc3.h
barks at anything older than that). Besides, there are almost no
occurrences of __FUNCTION__ left in the tree.
[akpm@linux-foundation.org: convert remaining __FUNCTION__ references]
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull live patching infrastructure from Jiri Kosina:
"Let me provide a bit of history first, before describing what is in
this pile.
Originally, there was kSplice as a standalone project that implemented
stop_machine()-based patching for the linux kernel. This project got
later acquired, and the current owner is providing live patching as a
proprietary service, without any intentions to have their
implementation merged.
Then, due to rising user/customer demand, both Red Hat and SUSE
started working on their own implementation (not knowing about each
other), and announced first versions roughly at the same time [1] [2].
The principle difference between the two solutions is how they are
making sure that the patching is performed in a consistent way when it
comes to different execution threads with respect to the semantic
nature of the change that is being introduced.
In a nutshell, kPatch is issuing stop_machine(), then looking at
stacks of all existing processess, and if it decides that the system
is in a state that can be patched safely, it proceeds insterting code
redirection machinery to the patched functions.
On the other hand, kGraft provides a per-thread consistency during one
single pass of a process through the kernel and performs a lazy
contignuous migration of threads from "unpatched" universe to the
"patched" one at safe checkpoints.
If interested in a more detailed discussion about the consistency
models and its possible combinations, please see the thread that
evolved around [3].
It pretty quickly became obvious to the interested parties that it's
absolutely impractical in this case to have several isolated solutions
for one task to co-exist in the kernel. During a dedicated Live
Kernel Patching track at LPC in Dusseldorf, all the interested parties
sat together and came up with a joint aproach that would work for both
distro vendors. Steven Rostedt took notes [4] from this meeting.
And the foundation for that aproach is what's present in this pull
request.
It provides a basic infrastructure for function "live patching" (i.e.
code redirection), including API for kernel modules containing the
actual patches, and API/ABI for userspace to be able to operate on the
patches (look up what patches are applied, enable/disable them, etc).
It's relatively simple and minimalistic, as it's making use of
existing kernel infrastructure (namely ftrace) as much as possible.
It's also self-contained, in a sense that it doesn't hook itself in
any other kernel subsystem (it doesn't even touch any other code).
It's now implemented for x86 only as a reference architecture, but
support for powerpc, s390 and arm is already in the works (adding
arch-specific support basically boils down to teaching ftrace about
regs-saving).
Once this common infrastructure gets merged, both Red Hat and SUSE
have agreed to immediately start porting their current solutions on
top of this, abandoning their out-of-tree code. The plan basically is
that each patch will be marked by flag(s) that would indicate which
consistency model it is willing to use (again, the details have been
sketched out already in the thread at [3]).
Before this happens, the current codebase can be used to patch a large
group of secruity/stability problems the patches for which are not too
complex (in a sense that they don't introduce non-trivial change of
function's return value semantics, they don't change layout of data
structures, etc) -- this corresponds to LEAVE_FUNCTION &&
SWITCH_FUNCTION semantics described at [3].
This tree has been in linux-next since December.
[1] https://lkml.org/lkml/2014/4/30/477
[2] https://lkml.org/lkml/2014/7/14/857
[3] https://lkml.org/lkml/2014/11/7/354
[4] http://linuxplumbersconf.org/2014/wp-content/uploads/2014/10/LPC2014_LivePatching.txt
[ The core code is introduced by the three commits authored by Seth
Jennings, which got a lot of changes incorporated during numerous
respins and reviews of the initial implementation. All the followup
commits have materialized only after public tree has been created,
so they were not folded into initial three commits so that the
public tree doesn't get rebased ]"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
livepatch: add missing newline to error message
livepatch: rename config to CONFIG_LIVEPATCH
livepatch: fix uninitialized return value
livepatch: support for repatching a function
livepatch: enforce patch stacking semantics
livepatch: change ARCH_HAVE_LIVE_PATCHING to HAVE_LIVE_PATCHING
livepatch: fix deferred module patching order
livepatch: handle ancient compilers with more grace
livepatch: kconfig: use bool instead of boolean
livepatch: samples: fix usage example comments
livepatch: MAINTAINERS: add git tree location
livepatch: use FTRACE_OPS_FL_IPMODIFY
livepatch: move x86 specific ftrace handler code to arch/x86
livepatch: samples: add sample live patching module
livepatch: kernel: add support for live patching
livepatch: kernel: add TAINT_LIVEPATCH
Commit 8eb23b9f35 ("sched: Debug nested sleeps") added code to report
on nested sleep conditions, which we generally want to avoid because the
inner sleeping operation can re-set the thread state to TASK_RUNNING,
but that will then cause the outer sleep loop not actually sleep when it
calls schedule.
However, that's actually valid traditional behavior, with the inner
sleep being some fairly rare case (like taking a sleeping lock that
normally doesn't actually need to sleep).
And the debug code would actually change the state of the task to
TASK_RUNNING internally, which makes that kind of traditional and
working code not work at all, because now the nested sleep doesn't just
sometimes cause the outer one to not block, but will cause it to happen
every time.
In particular, it will cause the cardbus kernel daemon (pccardd) to
basically busy-loop doing scheduling, converting a laptop into a heater,
as reported by Bruno Prémont. But there may be other legacy uses of
that nested sleep model in other drivers that are also likely to never
get converted to the new model.
This fixes both cases:
- don't set TASK_RUNNING when the nested condition happens (note: even
if WARN_ONCE() only _warns_ once, the return value isn't whether the
warning happened, but whether the condition for the warning was true.
So despite the warning only happening once, the "if (WARN_ON(..))"
would trigger for every nested sleep.
- in the cases where we knowingly disable the warning by using
"sched_annotate_sleep()", don't change the task state (that is used
for all core scheduling decisions), instead use '->task_state_change'
that is used for the debugging decision itself.
(Credit for the second part of the fix goes to Oleg Nesterov: "Can't we
avoid this subtle change in behaviour DEBUG_ATOMIC_SLEEP adds?" with the
suggested change to use 'task_state_change' as part of the test)
Reported-and-bisected-by: Bruno Prémont <bonbons@linux-vserver.org>
Tested-by: Rafael J Wysocki <rjw@rjwysocki.net>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>,
Cc: Ilya Dryomov <ilya.dryomov@inktank.com>,
Cc: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Hurley <peter@hurleysoftware.com>,
Cc: Davidlohr Bueso <dave@stgolabs.net>,
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds a new taint flag to indicate when the kernel or a kernel
module has been live patched. This will provide a clean indication in
bug reports that live patching was used.
Additionally, if the crash occurs in a live patched function, the live
patch module will appear beside the patched function in the backtrace.
Signed-off-by: Seth Jennings <sjenning@redhat.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Here's the big tty/serial driver update for 3.19-rc1.
There are a number of TTY core changes/fixes in here from Peter Hurley
that have all been teted in linux-next for a long time now. There are
also the normal serial driver updates as well, full details in the
changelog below.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver updates from Greg KH:
"Here's the big tty/serial driver update for 3.19-rc1.
There are a number of TTY core changes/fixes in here from Peter Hurley
that have all been teted in linux-next for a long time now. There are
also the normal serial driver updates as well, full details in the
changelog below"
* tag 'tty-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (219 commits)
serial: pxa: hold port.lock when reporting modem line changes
tty-hvsi_lib: Deletion of an unnecessary check before the function call "tty_kref_put"
tty: Deletion of unnecessary checks before two function calls
n_tty: Fix read_buf race condition, increment read_head after pushing data
serial: of-serial: add PM suspend/resume support
Revert "serial: of-serial: add PM suspend/resume support"
Revert "serial: of-serial: fix up PM ops on no_console_suspend and port type"
serial: 8250: don't attempt a trylock if in sysrq
serial: core: Add big-endian iotype
serial: samsung: use port->fifosize instead of hardcoded values
serial: samsung: prefer to use fifosize from driver data
serial: samsung: fix style problems
serial: samsung: wait for transfer completion before clock disable
serial: icom: fix error return code
serial: tegra: clean up tty-flag assignments
serial: Fix io address assign flow with Fintek PCI-to-UART Product
serial: mxs-auart: fix tx_empty against shift register
serial: mxs-auart: fix gpio change detection on interrupt
serial: mxs-auart: Fix mxs_auart_set_ldisc()
serial: 8250_dw: Use 64-bit access for OCTEON.
...
There have been several times where I have had to rebuild a kernel to
cause a panic when hitting a WARN() in the code in order to get a crash
dump from a system. Sometimes this is easy to do, other times (such as
in the case of a remote admin) it is not trivial to send new images to
the user.
A much easier method would be a switch to change the WARN() over to a
panic. This makes debugging easier in that I can now test the actual
image the WARN() was seen on and I do not have to engage in remote
debugging.
This patch adds a panic_on_warn kernel parameter and
/proc/sys/kernel/panic_on_warn calls panic() in the
warn_slowpath_common() path. The function will still print out the
location of the warning.
An example of the panic_on_warn output:
The first line below is from the WARN_ON() to output the WARN_ON()'s
location. After that the panic() output is displayed.
WARNING: CPU: 30 PID: 11698 at /home/prarit/dummy_module/dummy-module.c:25 init_dummy+0x1f/0x30 [dummy_module]()
Kernel panic - not syncing: panic_on_warn set ...
CPU: 30 PID: 11698 Comm: insmod Tainted: G W OE 3.17.0+ #57
Hardware name: Intel Corporation S2600CP/S2600CP, BIOS RMLSDP.86I.00.29.D696.1311111329 11/11/2013
0000000000000000 000000008e3f87df ffff88080f093c38 ffffffff81665190
0000000000000000 ffffffff818aea3d ffff88080f093cb8 ffffffff8165e2ec
ffffffff00000008 ffff88080f093cc8 ffff88080f093c68 000000008e3f87df
Call Trace:
[<ffffffff81665190>] dump_stack+0x46/0x58
[<ffffffff8165e2ec>] panic+0xd0/0x204
[<ffffffffa038e05f>] ? init_dummy+0x1f/0x30 [dummy_module]
[<ffffffff81076b90>] warn_slowpath_common+0xd0/0xd0
[<ffffffffa038e040>] ? dummy_greetings+0x40/0x40 [dummy_module]
[<ffffffff81076c8a>] warn_slowpath_null+0x1a/0x20
[<ffffffffa038e05f>] init_dummy+0x1f/0x30 [dummy_module]
[<ffffffff81002144>] do_one_initcall+0xd4/0x210
[<ffffffff811b52c2>] ? __vunmap+0xc2/0x110
[<ffffffff810f8889>] load_module+0x16a9/0x1b30
[<ffffffff810f3d30>] ? store_uevent+0x70/0x70
[<ffffffff810f49b9>] ? copy_module_from_fd.isra.44+0x129/0x180
[<ffffffff810f8ec6>] SyS_finit_module+0xa6/0xd0
[<ffffffff8166cf29>] system_call_fastpath+0x12/0x17
Successfully tested by me.
hpa said: There is another very valid use for this: many operators would
rather a machine shuts down than being potentially compromised either
functionally or security-wise.
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
tiocspgrp() is the lone caller of session_of_pgrp(); relocate and
limit to file scope.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cond_resched() is a preemption point, not strictly a blocking
primitive, so exclude it from the ->state test.
In particular, preemption preserves task_struct::state.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: tglx@linutronix.de
Cc: ilya.dryomov@inktank.com
Cc: umgwanakikbuti@gmail.com
Cc: oleg@redhat.com
Cc: Alex Elder <alex.elder@linaro.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Axel Lin <axel.lin@ingics.com>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20140924082242.656559952@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
do_wait() is a big wait loop, but we set TASK_RUNNING too late; we end
up calling potential sleeps before we reset it.
Not strictly a bug since we're guaranteed to exit the loop and not
call schedule(); put in annotations to quiet might_sleep().
WARNING: CPU: 0 PID: 1 at ../kernel/sched/core.c:7123 __might_sleep+0x7e/0x90()
do not call blocking ops when !TASK_RUNNING; state=1 set at [<ffffffff8109a788>] do_wait+0x88/0x270
Call Trace:
[<ffffffff81694991>] dump_stack+0x4e/0x7a
[<ffffffff8109877c>] warn_slowpath_common+0x8c/0xc0
[<ffffffff8109886c>] warn_slowpath_fmt+0x4c/0x50
[<ffffffff810bca6e>] __might_sleep+0x7e/0x90
[<ffffffff811a1c15>] might_fault+0x55/0xb0
[<ffffffff8109a3fb>] wait_consider_task+0x90b/0xc10
[<ffffffff8109a804>] do_wait+0x104/0x270
[<ffffffff8109b837>] SyS_wait4+0x77/0x100
[<ffffffff8169d692>] system_call_fastpath+0x16/0x1b
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: tglx@linutronix.de
Cc: umgwanakikbuti@gmail.com
Cc: ilya.dryomov@inktank.com
Cc: Alex Elder <alex.elder@linaro.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Axel Lin <axel.lin@ingics.com>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Guillaume Morin <guillaume@morinfr.org>
Cc: Ionut Alexa <ionut.m.alexa@gmail.com>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Michal Schmidt <mschmidt@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20140924082242.186408915@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 EFI updates from Peter Anvin:
"This patchset falls under the "maintainers that grovel" clause in the
v3.18-rc1 announcement. We had intended to push it late in the merge
window since we got it into the -tip tree relatively late.
Many of these are relatively simple things, but there are a couple of
key bits, especially Ard's and Matt's patches"
* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
rtc: Disable EFI rtc for x86
efi: rtc-efi: Export platform:rtc-efi as module alias
efi: Delete the in_nmi() conditional runtime locking
efi: Provide a non-blocking SetVariable() operation
x86/efi: Adding efi_printks on memory allocationa and pci.reads
x86/efi: Mark initialization code as such
x86/efi: Update comment regarding required phys mapped EFI services
x86/efi: Unexport add_efi_memmap variable
x86/efi: Remove unused efi_call* macros
efi: Resolve some shadow warnings
arm64: efi: Format EFI memory type & attrs with efi_md_typeattr_format()
ia64: efi: Format EFI memory type & attrs with efi_md_typeattr_format()
x86: efi: Format EFI memory type & attrs with efi_md_typeattr_format()
efi: Introduce efi_md_typeattr_format()
efi: Add macro for EFI_MEMORY_UCE memory attribute
x86/efi: Clear EFI_RUNTIME_SERVICES if failing to enter virtual mode
arm64/efi: Do not enter virtual mode if booting with efi=noruntime or noefi
arm64/efi: uefi_init error handling fix
efi: Add kernel param efi=noruntime
lib: Add a generic cmdline parse function parse_option_str
...
Remove obsolete and unused strict_strto* functions
Signed-off-by: Daniel Walter <dwalter@google.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull security subsystem updates from James Morris.
Mostly ima, selinux, smack and key handling updates.
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (65 commits)
integrity: do zero padding of the key id
KEYS: output last portion of fingerprint in /proc/keys
KEYS: strip 'id:' from ca_keyid
KEYS: use swapped SKID for performing partial matching
KEYS: Restore partial ID matching functionality for asymmetric keys
X.509: If available, use the raw subjKeyId to form the key description
KEYS: handle error code encoded in pointer
selinux: normalize audit log formatting
selinux: cleanup error reporting in selinux_nlmsg_perm()
KEYS: Check hex2bin()'s return when generating an asymmetric key ID
ima: detect violations for mmaped files
ima: fix race condition on ima_rdwr_violation_check and process_measurement
ima: added ima_policy_flag variable
ima: return an error code from ima_add_boot_aggregate()
ima: provide 'ima_appraise=log' kernel option
ima: move keyring initialization to ima_init()
PKCS#7: Handle PKCS#7 messages that contain no X.509 certs
PKCS#7: Better handling of unsupported crypto
KEYS: Overhaul key identification when searching for asymmetric keys
KEYS: Implement binary asymmetric key ID handling
...
Instead of open-coding clamp_t macro min_t and max_t the way clamp macro
does and instead of open-coding clamp_val simply use clamp_t.
Furthermore, normalise argument naming in the macros to be lo and hi.
Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Cc: Mark Rustad <mark.d.rustad@intel.com>
Cc: "Kirsher, Jeffrey T" <jeffrey.t.kirsher@intel.com>
Cc: Hagen Paul Pfeifer <hagen@jauu.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There should be a generic function to parse params like a=b,c
Adding parse_option_str in lib/cmdline.c which will return true
if there's specified option set in the params.
Also updated efi=old_map parsing code to use the new function
Signed-off-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Provide a function to convert a buffer of binary data into an unterminated
ascii hex string representation of that data.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
This taint flag will be set if the system has ever entered a softlockup
state. Similar to TAINT_WARN it is useful to know whether or not the
system has been in a softlockup state when debugging.
[akpm@linux-foundation.org: apply the taint before calling panic()]
Signed-off-by: Josh Hunt <johunt@akamai.com>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It's been nearly 3 years now since commit 55036ba76b ("lib: rename
pack_hex_byte() to hex_byte_pack()") so it's time to remove this
deprecated and unused static inline.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This check was introduced in 2006 by Alexey Dobriyan (9774a1f54f)
for module parameters; we removed it when we unified the check into
VERIFY_OCTAL_PERMISSIONS() as sysfs didn't have the same requirement.
Now all those users are fixed, reintroduce it.
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Use bool instead of int as the return type.
All uses are tested with !.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
a staging driver; fix included. Greg KH said he'd take the patch
but hadn't as the merge window opened, so it's included here
to avoid breaking build.
Cheers,
Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull module updates from Rusty Russell:
"Nothing major: the stricter permissions checking for sysfs broke a
staging driver; fix included. Greg KH said he'd take the patch but
hadn't as the merge window opened, so it's included here to avoid
breaking build"
* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
staging: fix up speakup kobject mode
Use 'E' instead of 'X' for unsigned module taint flag.
VERIFY_OCTAL_PERMISSIONS: stricter checking for sysfs perms.
kallsyms: fix percpu vars on x86-64 with relocation.
kallsyms: generalize address range checking
module: LLVMLinux: Remove unused function warning from __param_check macro
Fix: module signature vs tracepoints: add new TAINT_UNSIGNED_MODULE
module: remove MODULE_GENERIC_TABLE
module: allow multiple calls to MODULE_DEVICE_TABLE() per module
module: use pr_cont
Summary of http://lkml.org/lkml/2014/3/14/363 :
Ted: module_param(queue_depth, int, 444)
Joe: 0444!
Rusty: User perms >= group perms >= other perms?
Joe: CLASS_ATTR, DEVICE_ATTR, SENSOR_ATTR and SENSOR_ATTR_2?
Side effect of stricter permissions means removing the unnecessary
S_IFREG from several callers.
Note that the BUILD_BUG_ON_ZERO((perm) & 2) test was removed: a fair
number of drivers fail this test, so that will be the debate for a
future patch.
Suggested-by: Joe Perches <joe@perches.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> for drivers/pci/slot.c
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Andy Shevchenko