Commit Graph

21315 Commits

Author SHA1 Message Date
David Rientjes da39da3a54 mm, oom: remove task_lock protecting comm printing
The oom killer takes task_lock() in a couple of places solely to protect
printing the task's comm.

A process's comm, including current's comm, may change due to
/proc/pid/comm or PR_SET_NAME.

The comm will always be NULL-terminated, so the worst race scenario would
only be during update.  We can tolerate a comm being printed that is in
the middle of an update to avoid taking the lock.

Other locations in the kernel have already dropped task_lock() when
printing comm, so this is consistent.

Signed-off-by: David Rientjes <rientjes@google.com>
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05 19:34:48 -08:00
Ulrich Obergfell 39d2da2161 kernel/watchdog.c: fix race between proc_watchdog_thresh() and watchdog_timer_fn()
Theoretically it is possible that the watchdog timer expires right at the
time when a user sets 'watchdog_thresh' to zero (note: this disables the
lockup detectors).  In this scenario, the is_softlockup() function - which
is called by the timer - could produce a false positive.

Fix this by checking the current value of 'watchdog_thresh'.

Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05 19:34:48 -08:00
Ulrich Obergfell a2a45b85ec kernel/watchdog.c: remove {get|put}_online_cpus() from watchdog_{park|unpark}_threads()
watchdog_{park|unpark}_threads() are now called in code paths that protect
themselves against CPU hotplug, so {get|put}_online_cpus() calls are
redundant and can be removed.

Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05 19:34:48 -08:00
Ulrich Obergfell 8614ddef82 kernel/watchdog.c: avoid races between /proc handlers and CPU hotplug
The handler functions for watchdog parameters in /proc/sys/kernel do not
protect themselves against races with CPU hotplug.  Hence, theoretically
it is possible that a new watchdog thread is started on a hotplugged CPU
while a parameter is being modified, and the thread could thus use a
parameter value that is 'in transition'.

For example, if 'watchdog_thresh' is being set to zero (note: this
disables the lockup detectors) the thread would erroneously use the value
zero as the sample period.

To avoid such races and to keep the /proc handler code consistent,
call
     {get|put}_online_cpus() in proc_watchdog_common()
     {get|put}_online_cpus() in proc_watchdog_thresh()
     {get|put}_online_cpus() in proc_watchdog_cpumask()

Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05 19:34:48 -08:00
Ulrich Obergfell ee89e71eb0 kernel/watchdog.c: avoid race between lockup detector suspend/resume and CPU hotplug
The lockup detector suspend/resume interface that was introduced by
commit 8c073d27d7 ("watchdog: introduce watchdog_suspend() and
watchdog_resume()") does not protect itself against races with CPU
hotplug.  Hence, theoretically it is possible that a new watchdog thread
is started on a hotplugged CPU while the lockup detector is suspended,
and the thread could thus interfere unexpectedly with the code that
requested to suspend the lockup detector.

Avoid the race by calling

  get_online_cpus() in lockup_detector_suspend()
  put_online_cpus() in lockup_detector_resume()

Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05 19:34:48 -08:00
Don Zickus ac1f591249 kernel/watchdog.c: add sysctl knob hardlockup_panic
The only way to enable a hardlockup to panic the machine is to set
'nmi_watchdog=panic' on the kernel command line.

This makes it awkward for end users and folks who want to run automate
tests (like myself).

Mimic the softlockup_panic knob and create a /proc/sys/kernel/hardlockup_panic
knob.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05 19:34:48 -08:00
Jiri Kosina 55537871ef kernel/watchdog.c: perform all-CPU backtrace in case of hard lockup
In many cases of hardlockup reports, it's actually not possible to know
why it triggered, because the CPU that got stuck is usually waiting on a
resource (with IRQs disabled) in posession of some other CPU is holding.

IOW, we are often looking at the stacktrace of the victim and not the
actual offender.

Introduce sysctl / cmdline parameter that makes it possible to have
hardlockup detector perform all-CPU backtrace.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05 19:34:48 -08:00
Ulrich Obergfell ee7fed5405 watchdog: do not unpark threads in watchdog_park_threads() on error
If kthread_park() returns an error, watchdog_park_threads() should not
blindly 'roll back' the already parked threads to the unparked state.
Instead leave it up to the callers to handle such errors appropriately in
their context.  For example, it is redundant to unpark the threads if the
lockup detectors will soon be disabled by the callers anyway.

Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05 19:34:48 -08:00
Ulrich Obergfell c993590c6a watchdog: implement error handling in lockup_detector_suspend()
lockup_detector_suspend() now handles errors from watchdog_park_threads().

Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05 19:34:48 -08:00
Ulrich Obergfell b43cb43cb8 watchdog: implement error handling in update_watchdog_all_cpus() and callers
update_watchdog_all_cpus() now passes errors from watchdog_park_threads()
up to functions in the call chain.  This allows watchdog_enable_all_cpus()
and proc_watchdog_update() to handle such errors too.

Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05 19:34:48 -08:00
Ulrich Obergfell 58cf690a09 watchdog: move watchdog_disable_all_cpus() outside of ifdef
Move watchdog_disable_all_cpus() outside of the ifdef so that it is
available if CONFIG_SYSCTL is not defined.  This is preparation for
"watchdog: implement error handling in update_watchdog_all_cpus() and
callers".

Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05 19:34:48 -08:00
Ulrich Obergfell d283c640ce watchdog: fix error handling in proc_watchdog_thresh()
The original watchdog_park_threads() function that was introduced by
commit 81a4beef91 ("watchdog: introduce watchdog_park_threads() and
watchdog_unpark_threads()") takes a very simple approach to handle
errors returned by kthread_park(): It attempts to roll back all watchdog
threads to the unparked state.  However, this may be undesired behaviour
from the perspective of the caller which may want to handle errors as
appropriate in its specific context.  Currently, there are two possible
call chains:

- watchdog suspend/resume interface

    lockup_detector_suspend
      watchdog_park_threads

- write to parameters in /proc/sys/kernel

    proc_watchdog_update
      watchdog_enable_all_cpus
        update_watchdog_all_cpus
          watchdog_park_threads

Instead of 'blindly' attempting to unpark the watchdog threads if a
kthread_park() call fails, the new approach is to disable the lockup
detectors in the above call chains.  Failure becomes visible to the user
as follows:

- error messages from lockup_detector_suspend()
                   or watchdog_enable_all_cpus()

- the state that can be read from /proc/sys/kernel/watchdog_enabled

- the 'write' system call in the latter call chain returns an error

I did not experience kthread_park() failures in practice, I used some
instrumentation to fake error returns from kthread_park() in order to test
the patches.

This patch (of 5):

Restore the previous value of watchdog_thresh _and_ sample_period if
proc_watchdog_update() returns an error.  The variables must be consistent
to avoid false positives of the lockup detectors.

Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05 19:34:48 -08:00
Yaowei Bai 451637e454 kernel/watchdog.c: is_hardlockup can be boolean
Make is_hardlockup return bool to improve readability due to this
particular function only using either one or zero as its return value.

No functional change.

Signed-off-by: Yaowei Bai <bywxiaobai@163.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05 19:34:48 -08:00
Linus Torvalds e880e87488 driver core update for 4.4-rc1
Here's the "big" driver core updates for 4.4-rc1.  Primarily a bunch of
 debugfs updates, with a smattering of minor driver core fixes and
 updates as well.
 
 All have been in linux-next for a long time.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here's the "big" driver core updates for 4.4-rc1.  Primarily a bunch
  of debugfs updates, with a smattering of minor driver core fixes and
  updates as well.

  All have been in linux-next for a long time"

* tag 'driver-core-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  debugfs: Add debugfs_create_ulong()
  of: to support binding numa node to specified device in devicetree
  debugfs: Add read-only/write-only bool file ops
  debugfs: Add read-only/write-only size_t file ops
  debugfs: Add read-only/write-only x64 file ops
  debugfs: Consolidate file mode checks in debugfs_create_*()
  Revert "mm: Check if section present during memory block (un)registering"
  driver-core: platform: Provide helpers for multi-driver modules
  mm: Check if section present during memory block (un)registering
  devres: fix a for loop bounds check
  CMA: fix CONFIG_CMA_SIZE_MBYTES overflow in 64bit
  base/platform: assert that dev_pm_domain callbacks are called unconditionally
  sysfs: correctly handle short reads on PREALLOC attrs.
  base: soc: siplify ida usage
  kobject: move EXPORT_SYMBOL() macros next to corresponding definitions
  kobject: explain what kobject's sd field is
  debugfs: document that debugfs_remove*() accepts NULL and error values
  debugfs: Pass bool pointer to debugfs_create_bool()
  ACPI / EC: Fix broken 64bit big-endian users of 'global_lock'
2015-11-04 21:50:37 -08:00
Linus Torvalds d9734e0d1c Merge branch 'for-4.4/core' of git://git.kernel.dk/linux-block
Pull core block updates from Jens Axboe:
 "This is the core block pull request for 4.4.  I've got a few more
  topic branches this time around, some of them will layer on top of the
  core+drivers changes and will come in a separate round.  So not a huge
  chunk of changes in this round.

  This pull request contains:

   - Enable blk-mq page allocation tracking with kmemleak, from Catalin.

   - Unused prototype removal in blk-mq from Christoph.

   - Cleanup of the q->blk_trace exchange, using cmpxchg instead of two
     xchg()'s, from Davidlohr.

   - A plug flush fix from Jeff.

   - Also from Jeff, a fix that means we don't have to update shared tag
     sets at init time unless we do a state change.  This cuts down boot
     times on thousands of devices a lot with scsi/blk-mq.

   - blk-mq waitqueue barrier fix from Kosuke.

   - Various fixes from Ming:

        - Fixes for segment merging and splitting, and checks, for
          the old core and blk-mq.

        - Potential blk-mq speedup by marking ctx pending at the end
          of a plug insertion batch in blk-mq.

        - direct-io no page dirty on kernel direct reads.

   - A WRITE_SYNC fix for mpage from Roman"

* 'for-4.4/core' of git://git.kernel.dk/linux-block:
  blk-mq: avoid excessive boot delays with large lun counts
  blktrace: re-write setting q->blk_trace
  blk-mq: mark ctx as pending at batch in flush plug path
  blk-mq: fix for trace_block_plug()
  block: check bio_mergeable() early before merging
  blk-mq: check bio_mergeable() early before merging
  block: avoid to merge splitted bio
  block: setup bi_phys_segments after splitting
  block: fix plug list flushing for nomerge queues
  blk-mq: remove unused blk_mq_clone_flush_request prototype
  blk-mq: fix waitqueue_active without memory barrier in block/blk-mq-tag.c
  fs: direct-io: don't dirtying pages for ITER_BVEC/ITER_KVEC direct read
  fs/mpage.c: forgotten WRITE_SYNC in case of data integrity write
  block: kmemleak: Track the page allocations for struct request
2015-11-04 20:28:10 -08:00
Linus Torvalds 0d51ce9ca1 Power management and ACPI updates for v4.4-rc1
- ACPICA update to upstream revision 20150930 (Bob Moore, Lv Zheng).
 
    The most significant change is to allow the AML debugger to be
    built into the kernel.  On top of that there is an update related
    to the NFIT table (the ACPI persistent memory interface)
    and a few fixes and cleanups.
 
  - ACPI CPPC2 (Collaborative Processor Performance Control v2)
    support along with a cpufreq frontend (Ashwin Chaugule).
 
    This can only be enabled on ARM64 at this point.
 
  - New ACPI infrastructure for the early probing of IRQ chips and
    clock sources (Marc Zyngier).
 
  - Support for a new hierarchical properties extension of the ACPI
    _DSD (Device Specific Data) device configuration object allowing
    the kernel to handle hierarchical properties (provided by the
    platform firmware this way) automatically and make them available
    to device drivers via the generic device properties interface
    (Rafael Wysocki).
 
  - Generic device properties API extension to obtain an index of
    certain string value in an array of strings, along the lines of
    of_property_match_string(), but working for all of the supported
    firmware node types, and support for the "dma-names" device
    property based on it (Mika Westerberg).
 
  - ACPI core fix to parse the MADT (Multiple APIC Description Table)
    entries in the order expected by platform firmware (and mandated
    by the specification) to avoid confusion on systems with more than
    255 logical CPUs (Lukasz Anaczkowski).
 
  - Consolidation of the ACPI-based handling of PCI host bridges
    on x86 and ia64 (Jiang Liu).
 
  - ACPI core fixes to ensure that the correct IRQ number is used to
    represent the SCI (System Control Interrupt) in the cases when
    it has been re-mapped (Chen Yu).
 
  - New ACPI backlight quirk for Lenovo IdeaPad S405 (Hans de Goede).
 
  - ACPI EC driver fixes (Lv Zheng).
 
  - Assorted ACPI fixes and cleanups (Dan Carpenter, Insu Yun, Jiri
    Kosina, Rami Rosen, Rasmus Villemoes).
 
  - New mechanism in the PM core allowing drivers to check if the
    platform firmware is going to be involved in the upcoming system
    suspend or if it has been involved in the suspend the system is
    resuming from at the moment (Rafael Wysocki).
 
    This should allow drivers to optimize their suspend/resume
    handling in some cases and the changes include a couple of users
    of it (the i8042 input driver, PCI PM).
 
  - PCI PM fix to prevent runtime-suspended devices with PME enabled
    from being resumed during system suspend even if they aren't
    configured to wake up the system from sleep (Rafael Wysocki).
 
  - New mechanism to report the number of a wakeup IRQ that woke up
    the system from sleep last time (Alexandra Yates).
 
  - Removal of unused interfaces from the generic power domains
    framework and fixes related to latency measurements in that
    code (Ulf Hansson, Daniel Lezcano).
 
  - cpufreq core sysfs interface rework to make it handle CPUs that
    share performance scaling settings (represented by a common
    cpufreq policy object) more symmetrically (Viresh Kumar).
 
    This should help to simplify the CPU offline/online handling among
    other things.
 
  - cpufreq core fixes and cleanups (Viresh Kumar).
 
  - intel_pstate fixes related to the Turbo Activation Ratio (TAR)
    mechanism on client platforms which causes the turbo P-states
    range to vary depending on platform firmware settings (Srinivas
    Pandruvada).
 
  - intel_pstate sysfs interface fix (Prarit Bhargava).
 
  - Assorted cpufreq driver (imx, tegra20, powernv, integrator) fixes
    and cleanups (Bai Ping, Bartlomiej Zolnierkiewicz, Shilpasri G
    Bhat, Luis de Bethencourt).
 
  - cpuidle mvebu driver cleanups (Russell King).
 
  - OPP (Operating Performance Points) framework code reorganization
    to make it more maintainable (Viresh Kumar).
 
  - Intel Broxton support for the RAPL (Running Average Power Limits)
    power capping driver (Amy Wiles).
 
  - Assorted power management code fixes and cleanups (Dan Carpenter,
    Geert Uytterhoeven, Geliang Tang, Luis de Bethencourt, Rasmus
    Villemoes).
 
 /
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Merge tag 'pm+acpi-4.4-rc1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management and ACPI updates from Rafael Wysocki:
 "Quite a new features are included this time.

  First off, the Collaborative Processor Performance Control interface
  (version 2) defined by ACPI will now be supported on ARM64 along with
  a cpufreq frontend for CPU performance scaling.

  Second, ACPI gets a new infrastructure for the early probing of IRQ
  chips and clock sources (along the lines of the existing similar
  mechanism for DT).

  Next, the ACPI core and the generic device properties API will now
  support a recently introduced hierarchical properties extension of the
  _DSD (Device Specific Data) ACPI device configuration object.  If the
  ACPI platform firmware uses that extension to organize device
  properties in a hierarchical way, the kernel will automatically handle
  it and make those properties available to device drivers via the
  generic device properties API.

  It also will be possible to build the ACPICA's AML interpreter
  debugger into the kernel now and use that to diagnose AML-related
  problems more efficiently.  In the future, this should make it
  possible to single-step AML execution and do similar things.
  Interesting stuff, although somewhat experimental at this point.

  Finally, the PM core gets a new mechanism that can be used by device
  drivers to distinguish between suspend-to-RAM (based on platform
  firmware support) and suspend-to-idle (or other variants of system
  suspend the platform firmware is not involved in) and possibly
  optimize their device suspend/resume handling accordingly.

  In addition to that, some existing features are re-organized quite
  substantially.

  First, the ACPI-based handling of PCI host bridges on x86 and ia64 is
  unified and the common code goes into the ACPI core (so as to reduce
  code duplication and eliminate non-essential differences between the
  two architectures in that area).

  Second, the Operating Performance Points (OPP) framework is
  reorganized to make the code easier to find and follow.

  Next, the cpufreq core's sysfs interface is reorganized to get rid of
  the "primary CPU" concept for configurations in which the same
  performance scaling settings are shared between multiple CPUs.

  Finally, some interfaces that aren't necessary any more are dropped
  from the generic power domains framework.

  On top of the above we have some minor extensions, cleanups and bug
  fixes in multiple places, as usual.

  Specifics:

   - ACPICA update to upstream revision 20150930 (Bob Moore, Lv Zheng).

     The most significant change is to allow the AML debugger to be
     built into the kernel.  On top of that there is an update related
     to the NFIT table (the ACPI persistent memory interface) and a few
     fixes and cleanups.

   - ACPI CPPC2 (Collaborative Processor Performance Control v2) support
     along with a cpufreq frontend (Ashwin Chaugule).

     This can only be enabled on ARM64 at this point.

   - New ACPI infrastructure for the early probing of IRQ chips and
     clock sources (Marc Zyngier).

   - Support for a new hierarchical properties extension of the ACPI
     _DSD (Device Specific Data) device configuration object allowing
     the kernel to handle hierarchical properties (provided by the
     platform firmware this way) automatically and make them available
     to device drivers via the generic device properties interface
     (Rafael Wysocki).

   - Generic device properties API extension to obtain an index of
     certain string value in an array of strings, along the lines of
     of_property_match_string(), but working for all of the supported
     firmware node types, and support for the "dma-names" device
     property based on it (Mika Westerberg).

   - ACPI core fix to parse the MADT (Multiple APIC Description Table)
     entries in the order expected by platform firmware (and mandated by
     the specification) to avoid confusion on systems with more than 255
     logical CPUs (Lukasz Anaczkowski).

   - Consolidation of the ACPI-based handling of PCI host bridges on x86
     and ia64 (Jiang Liu).

   - ACPI core fixes to ensure that the correct IRQ number is used to
     represent the SCI (System Control Interrupt) in the cases when it
     has been re-mapped (Chen Yu).

   - New ACPI backlight quirk for Lenovo IdeaPad S405 (Hans de Goede).

   - ACPI EC driver fixes (Lv Zheng).

   - Assorted ACPI fixes and cleanups (Dan Carpenter, Insu Yun, Jiri
     Kosina, Rami Rosen, Rasmus Villemoes).

   - New mechanism in the PM core allowing drivers to check if the
     platform firmware is going to be involved in the upcoming system
     suspend or if it has been involved in the suspend the system is
     resuming from at the moment (Rafael Wysocki).

     This should allow drivers to optimize their suspend/resume handling
     in some cases and the changes include a couple of users of it (the
     i8042 input driver, PCI PM).

   - PCI PM fix to prevent runtime-suspended devices with PME enabled
     from being resumed during system suspend even if they aren't
     configured to wake up the system from sleep (Rafael Wysocki).

   - New mechanism to report the number of a wakeup IRQ that woke up the
     system from sleep last time (Alexandra Yates).

   - Removal of unused interfaces from the generic power domains
     framework and fixes related to latency measurements in that code
     (Ulf Hansson, Daniel Lezcano).

   - cpufreq core sysfs interface rework to make it handle CPUs that
     share performance scaling settings (represented by a common cpufreq
     policy object) more symmetrically (Viresh Kumar).

     This should help to simplify the CPU offline/online handling among
     other things.

   - cpufreq core fixes and cleanups (Viresh Kumar).

   - intel_pstate fixes related to the Turbo Activation Ratio (TAR)
     mechanism on client platforms which causes the turbo P-states range
     to vary depending on platform firmware settings (Srinivas
     Pandruvada).

   - intel_pstate sysfs interface fix (Prarit Bhargava).

   - Assorted cpufreq driver (imx, tegra20, powernv, integrator) fixes
     and cleanups (Bai Ping, Bartlomiej Zolnierkiewicz, Shilpasri G
     Bhat, Luis de Bethencourt).

   - cpuidle mvebu driver cleanups (Russell King).

   - OPP (Operating Performance Points) framework code reorganization to
     make it more maintainable (Viresh Kumar).

   - Intel Broxton support for the RAPL (Running Average Power Limits)
     power capping driver (Amy Wiles).

   - Assorted power management code fixes and cleanups (Dan Carpenter,
     Geert Uytterhoeven, Geliang Tang, Luis de Bethencourt, Rasmus
     Villemoes)"

* tag 'pm+acpi-4.4-rc1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (108 commits)
  cpufreq: postfix policy directory with the first CPU in related_cpus
  cpufreq: create cpu/cpufreq/policyX directories
  cpufreq: remove cpufreq_sysfs_{create|remove}_file()
  cpufreq: create cpu/cpufreq at boot time
  cpufreq: Use cpumask_copy instead of cpumask_or to copy a mask
  cpufreq: ondemand: Drop unnecessary locks from update_sampling_rate()
  PM / Domains: Merge measurements for PM QoS device latencies
  PM / Domains: Don't measure ->start|stop() latency in system PM callbacks
  PM / clk: Fix broken build due to non-matching code and header #ifdefs
  ACPI / Documentation: add copy_dsdt to ACPI format options
  ACPI / sysfs: correctly check failing memory allocation
  ACPI / video: Add a quirk to force native backlight on Lenovo IdeaPad S405
  ACPI / CPPC: Fix potential memory leak
  ACPI / CPPC: signedness bug in register_pcc_channel()
  ACPI / PAD: power_saving_thread() is not freezable
  ACPI / PM: Fix incorrect wakeup IRQ setting during suspend-to-idle
  ACPI: Using correct irq when waiting for events
  ACPI: Use correct IRQ when uninstalling ACPI interrupt handler
  cpuidle: mvebu: disable the bind/unbind attributes and use builtin_platform_driver
  cpuidle: mvebu: clean up multiple platform drivers
  ...
2015-11-04 18:10:13 -08:00
Linus Torvalds 2dc10ad81f arm64 updates for 4.4:
- "genirq: Introduce generic irq migration for cpu hotunplugged" patch
   merged from tip/irq/for-arm to allow the arm64-specific part to be
   upstreamed via the arm64 tree
 
 - CPU feature detection reworked to cope with heterogeneous systems
   where CPUs may not have exactly the same features. The features
   reported by the kernel via internal data structures or ELF_HWCAP are
   delayed until all the CPUs are up (and before user space starts)
 
 - Support for 16KB pages, with the additional bonus of a 36-bit VA
   space, though the latter only depending on EXPERT
 
 - Implement native {relaxed, acquire, release} atomics for arm64
 
 - New ASID allocation algorithm which avoids IPI on roll-over, together
   with TLB invalidation optimisations (using local vs global where
   feasible)
 
 - KASan support for arm64
 
 - EFI_STUB clean-up and isolation for the kernel proper (required by
   KASan)
 
 - copy_{to,from,in}_user optimisations (sharing the memcpy template)
 
 - perf: moving arm64 to the arm32/64 shared PMU framework
 
 - L1_CACHE_BYTES increased to 128 to accommodate Cavium hardware
 
 - Support for the contiguous PTE hint on kernel mapping (16 consecutive
   entries may be able to use a single TLB entry)
 
 - Generic CONFIG_HZ now used on arm64
 
 - defconfig updates
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:

 - "genirq: Introduce generic irq migration for cpu hotunplugged" patch
   merged from tip/irq/for-arm to allow the arm64-specific part to be
   upstreamed via the arm64 tree

 - CPU feature detection reworked to cope with heterogeneous systems
   where CPUs may not have exactly the same features.  The features
   reported by the kernel via internal data structures or ELF_HWCAP are
   delayed until all the CPUs are up (and before user space starts)

 - Support for 16KB pages, with the additional bonus of a 36-bit VA
   space, though the latter only depending on EXPERT

 - Implement native {relaxed, acquire, release} atomics for arm64

 - New ASID allocation algorithm which avoids IPI on roll-over, together
   with TLB invalidation optimisations (using local vs global where
   feasible)

 - KASan support for arm64

 - EFI_STUB clean-up and isolation for the kernel proper (required by
   KASan)

 - copy_{to,from,in}_user optimisations (sharing the memcpy template)

 - perf: moving arm64 to the arm32/64 shared PMU framework

 - L1_CACHE_BYTES increased to 128 to accommodate Cavium hardware

 - Support for the contiguous PTE hint on kernel mapping (16 consecutive
   entries may be able to use a single TLB entry)

 - Generic CONFIG_HZ now used on arm64

 - defconfig updates

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (91 commits)
  arm64/efi: fix libstub build under CONFIG_MODVERSIONS
  ARM64: Enable multi-core scheduler support by default
  arm64/efi: move arm64 specific stub C code to libstub
  arm64: page-align sections for DEBUG_RODATA
  arm64: Fix build with CONFIG_ZONE_DMA=n
  arm64: Fix compat register mappings
  arm64: Increase the max granular size
  arm64: remove bogus TASK_SIZE_64 check
  arm64: make Timer Interrupt Frequency selectable
  arm64/mm: use PAGE_ALIGNED instead of IS_ALIGNED
  arm64: cachetype: fix definitions of ICACHEF_* flags
  arm64: cpufeature: declare enable_cpu_capabilities as static
  genirq: Make the cpuhotplug migration code less noisy
  arm64: Constify hwcap name string arrays
  arm64/kvm: Make use of the system wide safe values
  arm64/debug: Make use of the system wide safe value
  arm64: Move FP/ASIMD hwcap handling to common code
  arm64/HWCAP: Use system wide safe values
  arm64/capabilities: Make use of system wide safe value
  arm64: Delay cpu feature capability checks
  ...
2015-11-04 14:47:13 -08:00
Linus Torvalds b0f85fa11a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

Changes of note:

 1) Allow to schedule ICMP packets in IPVS, from Alex Gartrell.

 2) Provide FIB table ID in ipv4 route dumps just as ipv6 does, from
    David Ahern.

 3) Allow the user to ask for the statistics to be filtered out of
    ipv4/ipv6 address netlink dumps.  From Sowmini Varadhan.

 4) More work to pass the network namespace context around deep into
    various packet path APIs, starting with the netfilter hooks.  From
    Eric W Biederman.

 5) Add layer 2 TX/RX checksum offloading to qeth driver, from Thomas
    Richter.

 6) Use usec resolution for SYN/ACK RTTs in TCP, from Yuchung Cheng.

 7) Support Very High Throughput in wireless MESH code, from Bob
    Copeland.

 8) Allow setting the ageing_time in switchdev/rocker.  From Scott
    Feldman.

 9) Properly autoload L2TP type modules, from Stephen Hemminger.

10) Fix and enable offload features by default in 8139cp driver, from
    David Woodhouse.

11) Support both ipv4 and ipv6 sockets in a single vxlan device, from
    Jiri Benc.

12) Fix CWND limiting of thin streams in TCP, from Bendik Rønning
    Opstad.

13) Fix IPSEC flowcache overflows on large systems, from Steffen
    Klassert.

14) Convert bridging to track VLANs using rhashtable entries rather than
    a bitmap.  From Nikolay Aleksandrov.

15) Make TCP listener handling completely lockless, this is a major
    accomplishment.  Incoming request sockets now live in the
    established hash table just like any other socket too.

    From Eric Dumazet.

15) Provide more bridging attributes to netlink, from Nikolay
    Aleksandrov.

16) Use hash based algorithm for ipv4 multipath routing, this was very
    long overdue.  From Peter Nørlund.

17) Several y2038 cures, mostly avoiding timespec.  From Arnd Bergmann.

18) Allow non-root execution of EBPF programs, from Alexei Starovoitov.

19) Support SO_INCOMING_CPU as setsockopt, from Eric Dumazet.  This
    influences the port binding selection logic used by SO_REUSEPORT.

20) Add ipv6 support to VRF, from David Ahern.

21) Add support for Mellanox Spectrum switch ASIC, from Jiri Pirko.

22) Add rtl8xxxu Realtek wireless driver, from Jes Sorensen.

23) Implement RACK loss recovery in TCP, from Yuchung Cheng.

24) Support multipath routes in MPLS, from Roopa Prabhu.

25) Fix POLLOUT notification for listening sockets in AF_UNIX, from Eric
    Dumazet.

26) Add new QED Qlogic river, from Yuval Mintz, Manish Chopra, and
    Sudarsana Kalluru.

27) Don't fetch timestamps on AF_UNIX sockets, from Hannes Frederic
    Sowa.

28) Support ipv6 geneve tunnels, from John W Linville.

29) Add flood control support to switchdev layer, from Ido Schimmel.

30) Fix CHECKSUM_PARTIAL handling of potentially fragmented frames, from
    Hannes Frederic Sowa.

31) Support persistent maps and progs in bpf, from Daniel Borkmann.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1790 commits)
  sh_eth: use DMA barriers
  switchdev: respect SKIP_EOPNOTSUPP flag in case there is no recursion
  net: sched: kill dead code in sch_choke.c
  irda: Delete an unnecessary check before the function call "irlmp_unregister_service"
  net: dsa: mv88e6xxx: include DSA ports in VLANs
  net: dsa: mv88e6xxx: disable SA learning for DSA and CPU ports
  net/core: fix for_each_netdev_feature
  vlan: Invoke driver vlan hooks only if device is present
  arcnet/com20020: add LEDS_CLASS dependency
  bpf, verifier: annotate verbose printer with __printf
  dp83640: Only wait for timestamps for packets with timestamping enabled.
  ptp: Change ptp_class to a proper bitmask
  dp83640: Prune rx timestamp list before reading from it
  dp83640: Delay scheduled work.
  dp83640: Include hash in timestamp/packet matching
  ipv6: fix tunnel error handling
  net/mlx5e: Fix LSO vlan insertion
  net/mlx5e: Re-eanble client vlan TX acceleration
  net/mlx5e: Return error in case mlx5e_set_features() fails
  net/mlx5e: Don't allow more than max supported channels
  ...
2015-11-04 09:41:05 -08:00
Linus Torvalds 53528695ff Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler changes from Ingo Molnar:
 "The main changes in this cycle were:

   - sched/fair load tracking fixes and cleanups (Byungchul Park)

   - Make load tracking frequency scale invariant (Dietmar Eggemann)

   - sched/deadline updates (Juri Lelli)

   - stop machine fixes, cleanups and enhancements for bugs triggered by
     CPU hotplug stress testing (Oleg Nesterov)

   - scheduler preemption code rework: remove PREEMPT_ACTIVE and related
     cleanups (Peter Zijlstra)

   - Rework the sched_info::run_delay code to fix races (Peter Zijlstra)

   - Optimize per entity utilization tracking (Peter Zijlstra)

   - ... misc other fixes, cleanups and smaller updates"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits)
  sched: Don't scan all-offline ->cpus_allowed twice if !CONFIG_CPUSETS
  sched: Move cpu_active() tests from stop_two_cpus() into migrate_swap_stop()
  sched: Start stopper early
  stop_machine: Kill cpu_stop_threads->setup() and cpu_stop_unpark()
  stop_machine: Kill smp_hotplug_thread->pre_unpark, introduce stop_machine_unpark()
  stop_machine: Change cpu_stop_queue_two_works() to rely on stopper->enabled
  stop_machine: Introduce __cpu_stop_queue_work() and cpu_stop_queue_two_works()
  stop_machine: Ensure that a queued callback will be called before cpu_stop_park()
  sched/x86: Fix typo in __switch_to() comments
  sched/core: Remove a parameter in the migrate_task_rq() function
  sched/core: Drop unlikely behind BUG_ON()
  sched/core: Fix task and run queue sched_info::run_delay inconsistencies
  sched/numa: Fix task_tick_fair() from disabling numa_balancing
  sched/core: Add preempt_count invariant check
  sched/core: More notrace annotations
  sched/core: Kill PREEMPT_ACTIVE
  sched/core, sched/x86: Kill thread_info::saved_preempt_count
  sched/core: Simplify preempt_count tests
  sched/core: Robustify preemption leak checks
  sched/core: Stop setting PREEMPT_ACTIVE
  ...
2015-11-03 18:03:50 -08:00
Linus Torvalds b831ef2cad Merge branch 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RAS changes from Ingo Molnar:
 "The main system reliability related changes were from x86, but also
  some generic RAS changes:

   - AMD MCE error injection subsystem enhancements.  (Aravind
     Gopalakrishnan)

   - Fix MCE and CPU hotplug interaction bug.  (Ashok Raj)

   - kcrash bootup robustness fix.  (Baoquan He)

   - kcrash cleanups.  (Borislav Petkov)

   - x86 microcode driver rework: simplify it by unmodularizing it and
     other cleanups.  (Borislav Petkov)"

* 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  x86/mce: Add a default case to the switch in __mcheck_cpu_ancient_init()
  x86/mce: Add a Scalable MCA vendor flags bit
  MAINTAINERS: Unify the microcode driver section
  x86/microcode/intel: Move #ifdef DEBUG inside the function
  x86/microcode/amd: Remove maintainers from comments
  x86/microcode: Remove modularization leftovers
  x86/microcode: Merge the early microcode loader
  x86/microcode: Unmodularize the microcode driver
  x86/mce: Fix thermal throttling reporting after kexec
  kexec/crash: Say which char is the unrecognized
  x86/setup/crash: Check memblock_reserve() retval
  x86/setup/crash: Cleanup some more
  x86/setup/crash: Remove alignment variable
  x86/setup: Cleanup crashkernel reservation functions
  x86/amd_nb, EDAC: Rename amd_get_node_id()
  x86/setup: Do not reserve crashkernel high memory if low reservation failed
  x86/microcode/amd: Do not overwrite final patch levels
  x86/microcode/amd: Extract current patch level read to a function
  x86/ras/mce_amd_inj: Inject bank 4 errors on the NBC
  x86/ras/mce_amd_inj: Trigger deferred and thresholding errors interrupts
  ...
2015-11-03 17:51:33 -08:00
Linus Torvalds b02ac6b18c Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "Kernel side changes:

   - Improve accuracy of perf/sched clock on x86.  (Adrian Hunter)

   - Intel DS and BTS updates.  (Alexander Shishkin)

   - Intel cstate PMU support.  (Kan Liang)

   - Add group read support to perf_event_read().  (Peter Zijlstra)

   - Branch call hardware sampling support, implemented on x86 and
     PowerPC.  (Stephane Eranian)

   - Event groups transactional interface enhancements.  (Sukadev
     Bhattiprolu)

   - Enable proper x86/intel/uncore PMU support on multi-segment PCI
     systems.  (Taku Izumi)

   - ... misc fixes and cleanups.

  The perf tooling team was very busy again with 200+ commits, the full
  diff doesn't fit into lkml size limits.  Here's an (incomplete) list
  of the tooling highlights:

  New features:

   - Change the default event used in all tools (record/top): use the
     most precise "cycles" hw counter available, i.e. when the user
     doesn't specify any event, it will try using cycles:ppp, cycles:pp,
     etc and fall back transparently until it finds a working counter.
     (Arnaldo Carvalho de Melo)

   - Integration of perf with eBPF that, given an eBPF .c source file
     (or .o file built for the 'bpf' target with clang), will get it
     automatically built, validated and loaded into the kernel via the
     sys_bpf syscall, which can then be used and seen using 'perf trace'
     and other tools.

     (Wang Nan)

  Various user interface improvements:

   - Automatic pager invocation on long help output.  (Namhyung Kim)

   - Search for more options when passing args to -h, e.g.: (Arnaldo
     Carvalho de Melo)

        $ perf report -h interface

        Usage: perf report [<options>]

         --gtk    Use the GTK2 interface
         --stdio  Use the stdio interface
         --tui    Use the TUI interface

   - Show ordered command line options when -h is used or when an
     unknown option is specified.  (Arnaldo Carvalho de Melo)

   - If options are passed after -h, show just its descriptions, not all
     options.  (Arnaldo Carvalho de Melo)

   - Implement column based horizontal scrolling in the hists browser
     (top, report), making it possible to use the TUI for things like
     'perf mem report' where there are many more columns than can fit in
     a terminal.  (Arnaldo Carvalho de Melo)

   - Enhance the error reporting of tracepoint event parsing, e.g.:

       $ oldperf record -e sched:sched_switc usleep 1
       event syntax error: 'sched:sched_switc'
                            \___ unknown tracepoint
       Run 'perf list' for a list of valid events

     Now we get the much nicer:

       $ perf record -e sched:sched_switc ls
       event syntax error: 'sched:sched_switc'
                            \___ can't access trace events

       Error: No permissions to read /sys/kernel/debug/tracing/events/sched/sched_switc
       Hint:  Try 'sudo mount -o remount,mode=755 /sys/kernel/debug'

     And after we have those mount point permissions fixed:

       $ perf record -e sched:sched_switc ls
       event syntax error: 'sched:sched_switc'
                            \___ unknown tracepoint

       Error: File /sys/kernel/debug/tracing/events/sched/sched_switc not found.
       Hint:  Perhaps this kernel misses some CONFIG_ setting to enable this feature?.

     I.e.  basically now the event parsing routing uses the strerror_open()
     routines introduced by and used in 'perf trace' work.  (Jiri Olsa)

   - Fail properly when pattern matching fails to find a tracepoint,
     i.e. '-e non:existent' was being correctly handled, with a proper
     error message about that not being a valid event, but '-e
     non:existent*' wasn't, fix it.  (Jiri Olsa)

   - Do event name substring search as last resort in 'perf list'.
     (Arnaldo Carvalho de Melo)

     E.g.:

       # perf list clock

       List of pre-defined events (to be used in -e):

        cpu-clock                                          [Software event]
        task-clock                                         [Software event]

        uncore_cbox_0/clockticks/                          [Kernel PMU event]
        uncore_cbox_1/clockticks/                          [Kernel PMU event]

        kvm:kvm_pvclock_update                             [Tracepoint event]
        kvm:kvm_update_master_clock                        [Tracepoint event]
        power:clock_disable                                [Tracepoint event]
        power:clock_enable                                 [Tracepoint event]
        power:clock_set_rate                               [Tracepoint event]
        syscalls:sys_enter_clock_adjtime                   [Tracepoint event]
        syscalls:sys_enter_clock_getres                    [Tracepoint event]
        syscalls:sys_enter_clock_gettime                   [Tracepoint event]
        syscalls:sys_enter_clock_nanosleep                 [Tracepoint event]
        syscalls:sys_enter_clock_settime                   [Tracepoint event]
        syscalls:sys_exit_clock_adjtime                    [Tracepoint event]
        syscalls:sys_exit_clock_getres                     [Tracepoint event]
        syscalls:sys_exit_clock_gettime                    [Tracepoint event]
        syscalls:sys_exit_clock_nanosleep                  [Tracepoint event]
        syscalls:sys_exit_clock_settime                    [Tracepoint event]

  Intel PT hardware tracing enhancements:

   - Accept a zero --itrace period, meaning "as often as possible".  In
     the case of Intel PT that is the same as a period of 1 and a unit
     of 'instructions' (i.e.  --itrace=i1i).  (Adrian Hunter)

   - Harmonize itrace's synthesized callchains with the existing
     --max-stack tool option.  (Adrian Hunter)

   - Allow time to be displayed in nanoseconds in 'perf script'.
     (Adrian Hunter)

   - Fix potential infinite loop when handling Intel PT timestamps.
     (Adrian Hunter)

   - Slighly improve Intel PT debug logging.  (Adrian Hunter)

   - Warn when AUX data has been lost, just like when processing
     PERF_RECORD_LOST.  (Adrian Hunter)

   - Further document export-to-postgresql.py script.  (Adrian Hunter)

   - Add option to synthesize branch stack from auxtrace data.  (Adrian
     Hunter)

  Misc notable changes:

   - Switch the default callchain output mode to 'graph,0.5,caller', to
     make it look like the default for other tools, reducing the
     learning curve for people used to 'caller' based viewing.  (Arnaldo
     Carvalho de Melo)

   - various call chain usability enhancements.  (Namhyung Kim)

   - Introduce the 'P' event modifier, meaning 'max precision level,
     please', i.e.:

        $ perf record -e cycles:P usleep 1

     Is now similar to:

        $ perf record usleep 1

     Useful, for instance, when specifying multiple events.  (Jiri Olsa)

   - Add 'socket' sort entry, to sort by the processor socket in 'perf
     top' and 'perf report'.  (Kan Liang)

   - Introduce --socket-filter to 'perf report', for filtering by
     processor socket.  (Kan Liang)

   - Add new "Zoom into Processor Socket" operation in the perf hists
     browser, used in 'perf top' and 'perf report'.  (Kan Liang)

   - Allow probing on kmodules without DWARF.  (Masami Hiramatsu)

   - Fix 'perf probe -l' for probes added to kernel module functions.
     (Masami Hiramatsu)

   - Preparatory work for the 'perf stat record' feature that will allow
     generating perf.data files with counting data in addition to the
     sampling mode we have now (Jiri Olsa)

   - Update libtraceevent KVM plugin.  (Paolo Bonzini)

   - ... plus lots of other enhancements that I failed to list properly,
     by: Adrian Hunter, Alexander Shishkin, Andi Kleen, Andrzej Hajda,
     Arnaldo Carvalho de Melo, Dima Kogan, Don Zickus, Geliang Tang, He
     Kuang, Huaitong Han, Ingo Molnar, Jan Stancek, Jiri Olsa, Kan
     Liang, Kirill Tkhai, Masami Hiramatsu, Matt Fleming, Namhyung Kim,
     Paolo Bonzini, Peter Zijlstra, Rabin Vincent, Scott Wood, Stephane
     Eranian, Sukadev Bhattiprolu, Taku Izumi, Vaishali Thakkar, Wang
     Nan, Yang Shi and Yunlong Song"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (260 commits)
  perf unwind: Pass symbol source to libunwind
  tools build: Fix libiberty feature detection
  perf tools: Compile scriptlets to BPF objects when passing '.c' to --event
  perf record: Add clang options for compiling BPF scripts
  perf bpf: Attach eBPF filter to perf event
  perf tools: Make sure fixdep is built before libbpf
  perf script: Enable printing of branch stack
  perf trace: Add cmd string table to decode sys_bpf first arg
  perf bpf: Collect perf_evsel in BPF object files
  perf tools: Load eBPF object into kernel
  perf tools: Create probe points for BPF programs
  perf tools: Enable passing bpf object file to --event
  perf ebpf: Add the libbpf glue
  perf tools: Make perf depend on libbpf
  perf symbols: Fix endless loop in dso__split_kallsyms_for_kcore
  perf tools: Enable pre-event inherit setting by config terms
  perf symbols: we can now read separate debug-info files based on a build ID
  perf symbols: Fix type error when reading a build-id
  perf tools: Search for more options when passing args to -h
  perf stat: Cache aggregated map entries in extra cpumap
  ...
2015-11-03 17:38:09 -08:00
Linus Torvalds 105ff3cbf2 atomic: remove all traces of READ_ONCE_CTRL() and atomic*_read_ctrl()
This seems to be a mis-reading of how alpha memory ordering works, and
is not backed up by the alpha architecture manual.  The helper functions
don't do anything special on any other architectures, and the arguments
that support them being safe on other architectures also argue that they
are safe on alpha.

Basically, the "control dependency" is between a previous read and a
subsequent write that is dependent on the value read.  Even if the
subsequent write is actually done speculatively, there is no way that
such a speculative write could be made visible to other cpu's until it
has been committed, which requires validating the speculation.

Note that most weakely ordered architectures (very much including alpha)
do not guarantee any ordering relationship between two loads that depend
on each other on a control dependency:

    read A
    if (val == 1)
        read B

because the conditional may be predicted, and the "read B" may be
speculatively moved up to before reading the value A.  So we require the
user to insert a smp_rmb() between the two accesses to be correct:

    read A;
    if (A == 1)
        smp_rmb()
        read B

Alpha is further special in that it can break that ordering even if the
*address* of B depends on the read of A, because the cacheline that is
read later may be stale unless you have a memory barrier in between the
pointer read and the read of the value behind a pointer:

    read ptr
    read offset(ptr)

whereas all other weakly ordered architectures guarantee that the data
dependency (as opposed to just a control dependency) will order the two
accesses.  As a result, alpha needs a "smp_read_barrier_depends()" in
between those two reads for them to be ordered.

The coontrol dependency that "READ_ONCE_CTRL()" and "atomic_read_ctrl()"
had was a control dependency to a subsequent *write*, however, and
nobody can finalize such a subsequent write without having actually done
the read.  And were you to write such a value to a "stale" cacheline
(the way the unordered reads came to be), that would seem to lose the
write entirely.

So the things that make alpha able to re-order reads even more
aggressively than other weak architectures do not seem to be relevant
for a subsequent write.  Alpha memory ordering may be strange, but
there's no real indication that it is *that* strange.

Also, the alpha architecture reference manual very explicitly talks
about the definition of "Dependence Constraints" in section 5.6.1.7,
where a preceding read dominates a subsequent write.

Such a dependence constraint admittedly does not impose a BEFORE (alpha
architecture term for globally visible ordering), but it does guarantee
that there can be no "causal loop".  I don't see how you could avoid
such a loop if another cpu could see the stored value and then impact
the value of the first read.  Put another way: the read and the write
could not be seen as being out of order wrt other cpus.

So I do not see how these "x_ctrl()" functions can currently be necessary.

I may have to eat my words at some point, but in the absense of clear
proof that alpha actually needs this, or indeed even an explanation of
how alpha could _possibly_ need it, I do not believe these functions are
called for.

And if it turns out that alpha really _does_ need a barrier for this
case, that barrier still should not be "smp_read_barrier_depends()".
We'd have to make up some new speciality barrier just for alpha, along
with the documentation for why it really is necessary.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul E McKenney <paulmck@us.ibm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-03 17:22:17 -08:00
Linus Torvalds d63a978865 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking changes from Ingo Molnar:
 "The main changes in this cycle were:

   - More gradual enhancements to atomic ops: new atomic*_read_ctrl()
     ops, synchronize atomic_{read,set}() ordering requirements between
     architectures, add atomic_long_t bitops.  (Peter Zijlstra)

   - Add _{relaxed|acquire|release}() variants for inc/dec atomics and
     use them in various locking primitives: mutex, rtmutex, mcs, rwsem.
     This enables weakly ordered architectures (such as arm64) to make
     use of more locking related optimizations.  (Davidlohr Bueso)

   - Implement atomic[64]_{inc,dec}_relaxed() on ARM.  (Will Deacon)

   - Futex kernel data cache footprint micro-optimization.  (Rasmus
     Villemoes)

   - pvqspinlock runtime overhead micro-optimization.  (Waiman Long)

   - misc smaller fixlets"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ARM, locking/atomics: Implement _relaxed variants of atomic[64]_{inc,dec}
  locking/rwsem: Use acquire/release semantics
  locking/mcs: Use acquire/release semantics
  locking/rtmutex: Use acquire/release semantics
  locking/mutex: Use acquire/release semantics
  locking/asm-generic: Add _{relaxed|acquire|release}() variants for inc/dec atomics
  atomic: Implement atomic_read_ctrl()
  atomic, arch: Audit atomic_{read,set}()
  atomic: Add atomic_long_t bitops
  futex: Force hot variables into a single cache line
  locking/pvqspinlock: Kick the PV CPU unconditionally when _Q_SLOW_VAL
  locking/osq: Relax atomic semantics
  locking/qrwlock: Rename ->lock to ->wait_lock
  locking/Documentation/lockstat: Fix typo - lokcing -> locking
  locking/atomics, cmpxchg: Privatize the inclusion of asm/cmpxchg.h
2015-11-03 16:10:43 -08:00
Linus Torvalds 2814228699 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU changes from Ingo Molnar:
 "The main changes in this cycle were:

   - Improvements to expedited grace periods (Paul E McKenney)

   - Performance improvements to and locktorture tests for percpu-rwsem
     (Oleg Nesterov, Paul E McKenney)

   - Torture-test changes (Paul E McKenney, Davidlohr Bueso)

   - Documentation updates (Paul E McKenney)

   - Miscellaneous fixes (Paul E McKenney, Boqun Feng, Oleg Nesterov,
     Patrick Marlier)"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
  fs/writeback, rcu: Don't use list_entry_rcu() for pointer offsetting in bdi_split_work_to_wbs()
  rcu: Better hotplug handling for synchronize_sched_expedited()
  rcu: Enable stall warnings for synchronize_rcu_expedited()
  rcu: Add tasks to expedited stall-warning messages
  rcu: Add online/offline info to expedited stall warning message
  rcu: Consolidate expedited CPU selection
  rcu: Prepare for consolidating expedited CPU selection
  cpu: Remove try_get_online_cpus()
  rcu: Stop excluding CPU hotplug in synchronize_sched_expedited()
  rcu: Stop silencing lockdep false positive for expedited grace periods
  rcu: Switch synchronize_sched_expedited() to IPI
  locktorture: Fix module unwind when bad torture_type specified
  torture: Forgive non-plural arguments
  rcutorture: Fix unused-function warning for torturing_tasks()
  rcutorture: Fix module unwind when bad torture_type specified
  rcu_sync: Cleanup the CONFIG_PROVE_RCU checks
  locking/percpu-rwsem: Clean up the lockdep annotations in percpu_down_read()
  locking/percpu-rwsem: Fix the comments outdated by rcu_sync
  locking/percpu-rwsem: Make use of the rcu_sync infrastructure
  locking/percpu-rwsem: Make percpu_free_rwsem() after kzalloc() safe
  ...
2015-11-03 15:40:38 -08:00
Linus Torvalds 6aa2fdb87c Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
 "The irq departement delivers:

   - Rework the irqdomain core infrastructure to accomodate ACPI based
     systems.  This is required to support ARM64 without creating
     artificial device tree nodes.

   - Sanitize the ACPI based ARM GIC initialization by making use of the
     new firmware independent irqdomain core

   - Further improvements to the generic MSI management

   - Generalize the irq migration on CPU hotplug

   - Improvements to the threaded interrupt infrastructure

   - Allow the migration of "chained" low level interrupt handlers

   - Allow optional force masking of interrupts in disable_irq[_nosysnc]

   - Support for two new interrupt chips - Sigh!

   - A larger set of errata fixes for ARM gicv3

   - The usual pile of fixes, updates, improvements and cleanups all
     over the place"

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits)
  Document that IRQ_NONE should be returned when IRQ not actually handled
  PCI/MSI: Allow the MSI domain to be device-specific
  PCI: Add per-device MSI domain hook
  of/irq: Use the msi-map property to provide device-specific MSI domain
  of/irq: Split of_msi_map_rid to reuse msi-map lookup
  irqchip/gic-v3-its: Parse new version of msi-parent property
  PCI/MSI: Use of_msi_get_domain instead of open-coded "msi-parent" parsing
  of/irq: Use of_msi_get_domain instead of open-coded "msi-parent" parsing
  of/irq: Add support code for multi-parent version of "msi-parent"
  irqchip/gic-v3-its: Add handling of PCI requester id.
  PCI/MSI: Add helper function pci_msi_domain_get_msi_rid().
  of/irq: Add new function of_msi_map_rid()
  Docs: dt: Add PCI MSI map bindings
  irqchip/gic-v2m: Add support for multiple MSI frames
  irqchip/gic-v3: Fix translation of LPIs after conversion to irq_fwspec
  irqchip/mxs: Add Alphascale ASM9260 support
  irqchip/mxs: Prepare driver for hardware with different offsets
  irqchip/mxs: Panic if ioremap or domain creation fails
  irqdomain: Documentation updates
  irqdomain/msi: Use fwnode instead of of_node
  ...
2015-11-03 14:40:01 -08:00
Linus Torvalds 7b2a4306f9 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "The timer departement provides:

   - More y2038 work in the area of ntp and pps.

   - Optimization of posix cpu timers

   - New time related selftests

   - Some new clocksource drivers

   - The usual pile of fixes, cleanups and improvements"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
  timeconst: Update path in comment
  timers/x86/hpet: Type adjustments
  clocksource/drivers/armada-370-xp: Implement ARM delay timer
  clocksource/drivers/tango_xtal: Add new timer for Tango SoCs
  clocksource/drivers/imx: Allow timer irq affinity change
  clocksource/drivers/exynos_mct: Use container_of() instead of this_cpu_ptr()
  clocksource/drivers/h8300_*: Remove unneeded memset()s
  clocksource/drivers/sh_cmt: Remove unneeded memset() in sh_cmt_setup()
  clocksource/drivers/em_sti: Remove unneeded memset()s
  clocksource/drivers/mediatek: Use GPT as sched clock source
  clockevents/drivers/mtk: Fix spurious interrupt leading to crash
  posix_cpu_timer: Reduce unnecessary sighand lock contention
  posix_cpu_timer: Convert cputimer->running to bool
  posix_cpu_timer: Check thread timers only when there are active thread timers
  posix_cpu_timer: Optimize fastpath_timer_check()
  timers, kselftest: Add 'adjtick' test to validate adjtimex() tick adjustments
  timers: Use __fls in apply_slack()
  clocksource: Remove return statement from void functions
  net: sfc: avoid using timespec
  ntp/pps: use y2038 safe types in pps_event_time
  ...
2015-11-03 14:13:41 -08:00
Daniel Borkmann 1d056d9c95 bpf, verifier: annotate verbose printer with __printf
The verbose() printer dumps the verifier state to user space, so let gcc
take care to check calls to verbose() for (future) errors. make with W=1
correctly suggests: function might be possible candidate for 'gnu_printf'
format attribute [-Wsuggest-attribute=format].

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-03 11:29:56 -05:00
Daniel Borkmann b2197755b2 bpf: add support for persistent maps/progs
This work adds support for "persistent" eBPF maps/programs. The term
"persistent" is to be understood that maps/programs have a facility
that lets them survive process termination. This is desired by various
eBPF subsystem users.

Just to name one example: tc classifier/action. Whenever tc parses
the ELF object, extracts and loads maps/progs into the kernel, these
file descriptors will be out of reach after the tc instance exits.
So a subsequent tc invocation won't be able to access/relocate on this
resource, and therefore maps cannot easily be shared, f.e. between the
ingress and egress networking data path.

The current workaround is that Unix domain sockets (UDS) need to be
instrumented in order to pass the created eBPF map/program file
descriptors to a third party management daemon through UDS' socket
passing facility. This makes it a bit complicated to deploy shared
eBPF maps or programs (programs f.e. for tail calls) among various
processes.

We've been brainstorming on how we could tackle this issue and various
approches have been tried out so far, which can be read up further in
the below reference.

The architecture we eventually ended up with is a minimal file system
that can hold map/prog objects. The file system is a per mount namespace
singleton, and the default mount point is /sys/fs/bpf/. Any subsequent
mounts within a given namespace will point to the same instance. The
file system allows for creating a user-defined directory structure.
The objects for maps/progs are created/fetched through bpf(2) with
two new commands (BPF_OBJ_PIN/BPF_OBJ_GET). I.e. a bpf file descriptor
along with a pathname is being passed to bpf(2) that in turn creates
(we call it eBPF object pinning) the file system nodes. Only the pathname
is being passed to bpf(2) for getting a new BPF file descriptor to an
existing node. The user can use that to access maps and progs later on,
through bpf(2). Removal of file system nodes is being managed through
normal VFS functions such as unlink(2), etc. The file system code is
kept to a very minimum and can be further extended later on.

The next step I'm working on is to add dump eBPF map/prog commands
to bpf(2), so that a specification from a given file descriptor can
be retrieved. This can be used by things like CRIU but also applications
can inspect the meta data after calling BPF_OBJ_GET.

Big thanks also to Alexei and Hannes who significantly contributed
in the design discussion that eventually let us end up with this
architecture here.

Reference: https://lkml.org/lkml/2015/10/15/925
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-02 22:48:39 -05:00
Daniel Borkmann e9d8afa90b bpf: consolidate bpf_prog_put{, _rcu} dismantle paths
We currently have duplicated cleanup code in bpf_prog_put() and
bpf_prog_put_rcu() cleanup paths. Back then we decided that it was
not worth it to make it a common helper called by both, but with
the recent addition of resource charging, we could have avoided
the fix in commit ac00737f4e ("bpf: Need to call bpf_prog_uncharge_memlock
from bpf_prog_put") if we would have had only a single, common path.
We can simplify it further by assigning aux->prog only once during
allocation time.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-02 22:48:39 -05:00
Daniel Borkmann c210129760 bpf: align and clean bpf_{map,prog}_get helpers
Add a bpf_map_get() function that we're going to use later on and
align/clean the remaining helpers a bit so that we have them a bit
more consistent:

  - __bpf_map_get() and __bpf_prog_get() that both work on the fd
    struct, check whether the descriptor is eBPF and return the
    pointer to the map/prog stored in the private data.

    Also, we can return f.file->private_data directly, the function
    signature is enough of a documentation already.

  - bpf_map_get() and bpf_prog_get() that both work on u32 user fd,
    call their respective __bpf_map_get()/__bpf_prog_get() variants,
    and take a reference.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-02 22:48:39 -05:00
Daniel Borkmann aa79781b65 bpf: abstract anon_inode_getfd invocations
Since we're going to use anon_inode_getfd() invocations in more than just
the current places, make a helper function for both, so that we only need
to pass a map/prog pointer to the helper itself in order to get a fd. The
new helpers are called bpf_map_new_fd() and bpf_prog_new_fd().

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-02 22:48:39 -05:00
Yang Shi ac00881f92 bpf: convert hashtab lock to raw lock
When running bpf samples on rt kernel, it reports the below warning:

BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:917
in_atomic(): 1, irqs_disabled(): 128, pid: 477, name: ping
Preemption disabled at:[<ffff80000017db58>] kprobe_perf_func+0x30/0x228

CPU: 3 PID: 477 Comm: ping Not tainted 4.1.10-rt8 #4
Hardware name: Freescale Layerscape 2085a RDB Board (DT)
Call trace:
[<ffff80000008a5b0>] dump_backtrace+0x0/0x128
[<ffff80000008a6f8>] show_stack+0x20/0x30
[<ffff8000007da90c>] dump_stack+0x7c/0xa0
[<ffff8000000e4830>] ___might_sleep+0x188/0x1a0
[<ffff8000007e2200>] rt_spin_lock+0x28/0x40
[<ffff80000018bf9c>] htab_map_update_elem+0x124/0x320
[<ffff80000018c718>] bpf_map_update_elem+0x40/0x58
[<ffff800000187658>] __bpf_prog_run+0xd48/0x1640
[<ffff80000017ca6c>] trace_call_bpf+0x8c/0x100
[<ffff80000017db58>] kprobe_perf_func+0x30/0x228
[<ffff80000017dd84>] kprobe_dispatcher+0x34/0x58
[<ffff8000007e399c>] kprobe_handler+0x114/0x250
[<ffff8000007e3bf4>] kprobe_breakpoint_handler+0x1c/0x30
[<ffff800000085b80>] brk_handler+0x88/0x98
[<ffff8000000822f0>] do_debug_exception+0x50/0xb8
Exception stack(0xffff808349687460 to 0xffff808349687580)
7460: 4ca2b600 ffff8083 4a3a7000 ffff8083 49687620 ffff8083 0069c5f8 ffff8000
7480: 00000001 00000000 007e0628 ffff8000 496874b0 ffff8083 007e1de8 ffff8000
74a0: 496874d0 ffff8083 0008e04c ffff8000 00000001 00000000 4ca2b600 ffff8083
74c0: 00ba2e80 ffff8000 49687528 ffff8083 49687510 ffff8083 000e5c70 ffff8000
74e0: 00c22348 ffff8000 00000000 ffff8083 49687510 ffff8083 000e5c74 ffff8000
7500: 4ca2b600 ffff8083 49401800 ffff8083 00000001 00000000 00000000 00000000
7520: 496874d0 ffff8083 00000000 00000000 00000000 00000000 00000000 00000000
7540: 2f2e2d2c 33323130 00000000 00000000 4c944500 ffff8083 00000000 00000000
7560: 00000000 00000000 008751e0 ffff8000 00000001 00000000 124e2d1d 00107b77

Convert hashtab lock to raw lock to avoid such warning.

Signed-off-by: Yang Shi <yang.shi@linaro.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-02 15:45:43 -05:00
Rafael J. Wysocki 9bb4064ca3 Merge branch 'pm-sleep'
* pm-sleep:
  PM / hibernate: fix a comment typo
  input: i8042: Avoid resetting controller on system suspend/resume
  PM / PCI / ACPI: Kick devices that might have been reset by firmware
  PM / sleep: Add flags to indicate platform firmware involvement
  PM / sleep: Drop pm_request_idle() from pm_generic_complete()
  PCI / PM: Avoid resuming more devices during system suspend
  PM / wakeup: wakeup_source_create: use kstrdup_const
  PM / sleep: Report interrupt that caused system wakeup
2015-11-02 00:52:19 +01:00
Linus Torvalds 95fc00a4e1 Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull memremap fix from Dan Williams:
 "The new memremap() api introduced in the 4.3 cycle to unify/replace
  ioremap_cache() and ioremap_wt() is mishandling the highmem case.
  This patch has received a build success notification from a
  0day-kbuild-robot run and has received an ack from Ard"

From the commit message:
 "The impact of this bug is low for now since the pmem driver is the
  only user of memremap(), but this is important to fix before more
  conversions to memremap arrive in 4.4"

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  memremap: fix highmem support
2015-11-01 14:13:54 -08:00
David S. Miller b75ec3af27 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-11-01 00:15:30 -04:00
Davidlohr Bueso cdea01b2bf blktrace: re-write setting q->blk_trace
This is really about simplifying the double xchg patterns into
a single cmpxchg, with the same logic. Other than the immediate
cleanup, there are some subtleties this change deals with:

(i) While the load of the old bt is fully ordered wrt everything,
ie:

        old_bt = xchg(&q->blk_trace, bt);             [barrier]
        if (old_bt)
	     (void) xchg(&q->blk_trace, old_bt);    [barrier]

blk_trace could still be changed between the xchg and the old_bt
load. Note that this description is merely theoretical and afaict
very small, but doing everything in a single context with cmpxchg
closes this potential race.

(ii) Ordering guarantees are obviously kept with cmpxchg.

(iii) Gets rid of the hacky-by-nature (void)xchg pattern.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
eviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-10-30 05:25:59 +09:00
Ingo Molnar e4340bbb07 Merge branch 'linus' into core/rcu, to fix up a semantic conflict
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-28 13:17:20 +01:00
Tycho Andersen f8e529ed94 seccomp, ptrace: add support for dumping seccomp filters
This patch adds support for dumping a process' (classic BPF) seccomp
filters via ptrace.

PTRACE_SECCOMP_GET_FILTER allows the tracer to dump the user's classic BPF
seccomp filters. addr should be an integer which represents the ith seccomp
filter (0 is the most recently installed filter). data should be a struct
sock_filter * with enough room for the ith filter, or NULL, in which case
the filter is not saved. The return value for this command is the number of
BPF instructions the program represents, or negative in the case of errors.
Command specific errors are ENOENT: which indicates that there is no ith
filter in this seccomp tree, and EMEDIUMTYPE, which indicates that the ith
filter was not installed as a classic BPF filter.

A caveat with this approach is that there is no way to get explicitly at
the heirarchy of seccomp filters, and users need to memcmp() filters to
decide which are inherited. This means that a task which installs two of
the same filter can potentially confuse users of this interface.

v2: * make save_orig const
    * check that the orig_prog exists (not necessary right now, but when
       grows eBPF support it will be)
    * s/n/filter_off and make it an unsigned long to match ptrace
    * count "down" the tree instead of "up" when passing a filter offset

v3: * don't take the current task's lock for inspecting its seccomp mode
    * use a 0x42** constant for the ptrace command value

v4: * don't copy to userspace while holding spinlocks

v5: * add another condition to WARN_ON

v6: * rebase on net-next

Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Acked-by: Kees Cook <keescook@chromium.org>
CC: Will Drewry <wad@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Pavel Emelyanov <xemul@parallels.com>
CC: Serge E. Hallyn <serge.hallyn@ubuntu.com>
CC: Alexei Starovoitov <ast@kernel.org>
CC: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-27 19:55:13 -07:00
Linus Torvalds 9e17f90702 Turns out we should have always been disabling preemption here;
someone finally caught it thanks to Peter Z's additional checks.
 
 Cheers,
 Rusty.
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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module preemption fix from Rusty Russell:
 "Turns out we should have always been disabling preemption here;
  someone finally caught it thanks to Peter Z's additional checks"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  module: Fix locking in symbol_put_addr()
2015-10-28 07:17:50 +09:00
Alexei Starovoitov 1075ef5950 bpf: make tracing helpers gpl only
exported perf symbols are GPL only, mark eBPF helper functions
used in tracing as GPL only as well.

Suggested-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-26 21:53:34 -07:00
Alexei Starovoitov 62544ce8e0 bpf: fix bpf_perf_event_read() helper
Fix safety checks for bpf_perf_event_read():
- only non-inherited events can be added to perf_event_array map
  (do this check statically at map insertion time)
- dynamically check that event is local and !pmu->count
Otherwise buggy bpf program can cause kernel splat.

Also fix error path after perf_event_attrs()
and remove redundant 'extern'.

Fixes: 35578d7984 ("bpf: Implement function bpf_perf_event_read() that get the selected hardware PMU conuter")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-26 21:49:26 -07:00
Dan Williams 182475b7a2 memremap: fix highmem support
Currently memremap checks if the range is "System RAM" and returns the
kernel linear address.  This is broken for highmem platforms where a
range may be "System RAM", but is not part of the kernel linear mapping.
Fallback to ioremap_cache() in these cases, to let the arch code attempt
to handle it.

Note that ARM ioremap will WARN when attempting to remap ram, and in
that case the caller needs to be fixed.  For this reason, existing
ioremap_cache() usages for ARM are already trained to avoid attempts to
remap ram.

The impact of this bug is low for now since the pmem driver is the only
user of memremap(), but this is important to fix before more conversions
to memremap arrive in 4.4.

Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-10-26 16:55:56 -04:00
Jason A. Donenfeld 03f136a207 timeconst: Update path in comment
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: hofrat@osadl.org
Link: http://lkml.kernel.org/r/1436894685-5868-1-git-send-email-Jason@zx2c4.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-10-26 10:06:06 +09:00
Linus Torvalds df55793680 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Misc fixes all around the map: an instrumentation fix, a nohz
  usability fix, a lockdep annotation fix and two task group scheduling
  fixes"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/core: Add missing lockdep_unpin() annotations
  sched/deadline: Fix migration of SCHED_DEADLINE tasks
  nohz: Revert "nohz: Set isolcpus when nohz_full is set"
  sched/fair: Update task group's load_avg after task migration
  sched/fair: Fix overly small weight for interactive group entities
  sched, tracing: Stop/start critical timings around the idle=poll idle loop
2015-10-23 22:31:39 +09:00
Linus Torvalds 9f30931a54 Merge branch 'akpm' (patches from Andrew)
Merge fixes from Andrew Morton:
 "9 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  ocfs2/dlm: unlock lockres spinlock before dlm_lockres_put
  fault-inject: fix inverted interval/probability values in printk
  lib/Kconfig.debug: disable -Wframe-larger-than warnings with KASAN=y
  mm: make sendfile(2) killable
  thp: use is_zero_pfn() only after pte_present() check
  mailmap: update Javier Martinez Canillas' email
  MAINTAINERS: add Sergey as zsmalloc reviewer
  mm: cma: fix incorrect type conversion for size during dma allocation
  kmod: don't run async usermode helper as a child of kworker thread
2015-10-23 22:10:51 +09:00
Peter Zijlstra 0aaafaabfc sched/core: Add missing lockdep_unpin() annotations
Luca and Wanpeng reported two missing annotations that led to
false lockdep complaints. Add the missing annotations.

Reported-by: Luca Abeni <luca.abeni@unitn.it>
Reported-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: cbce1a6867 ("sched,lockdep: Employ lock pinning")
Link: http://lkml.kernel.org/r/20151023095008.GY17308@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-23 12:02:10 +02:00
Oleg Nesterov 5211613978 kmod: don't run async usermode helper as a child of kworker thread
call_usermodehelper_exec_sync() does fork() + wait() with "unignored"
SIGCHLD.  What we have missed is that this worker thread can have other
children previously forked by call_usermodehelper_exec_work() without
UMH_WAIT_PROC.  If such a child exits in between it becomes a zombie
because auto-reaping only works if SIGCHLD is ignored, and nobody can
reap it (unless/until this worker thread exits too).

Change the !UMH_WAIT_PROC case to use CLONE_PARENT.

Note: this is only first step.  All PF_KTHREAD tasks, even created by
kernel_thread() should have ->parent == kthreadd by default.

Fixes: bb304a5c6f ("kmod: handle UMH_WAIT_PROC from system unbound workqueue")
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-10-23 17:55:10 +09:00
Catalin Marinas 6bccb4955c Merge branch 'irq/for-arm' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
This is an incremental fix for a patch previously pulled from tip
irq/for-arm.

* 'irq/for-arm' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Make the cpuhotplug migration code less noisy
2015-10-22 17:31:10 +01:00
Alexei Starovoitov a43eec3042 bpf: introduce bpf_perf_event_output() helper
This helper is used to send raw data from eBPF program into
special PERF_TYPE_SOFTWARE/PERF_COUNT_SW_BPF_OUTPUT perf_event.
User space needs to perf_event_open() it (either for one or all cpus) and
store FD into perf_event_array (similar to bpf_perf_event_read() helper)
before eBPF program can send data into it.

Today the programs triggered by kprobe collect the data and either store
it into the maps or print it via bpf_trace_printk() where latter is the debug
facility and not suitable to stream the data. This new helper replaces
such bpf_trace_printk() usage and allows programs to have dedicated
channel into user space for post-processing of the raw data collected.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-22 06:42:15 -07:00
Alexei Starovoitov fa128e6a14 perf: pad raw data samples automatically
Instead of WARN_ON in perf_event_output() on unpaded raw samples,
pad them automatically.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-22 06:42:13 -07:00