Tetsuo has reported that oom_kill_allocating_task=1 will cause
oom_reaper_list corruption because oom_kill_process doesn't follow
standard OOM exclusion (aka ignores TIF_MEMDIE) and allows to enqueue
the same task multiple times - e.g.  by sacrificing the same child
multiple times.

This patch fixes the issue by introducing a new MMF_OOM_KILLED mm flag
which is set in oom_kill_process atomically and oom reaper is disabled
if the flag was already set.
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

wake_oom_reaper has allowed only 1 oom victim to be queued.  The main
reason for that was the simplicity as other solutions would require some
way of queuing.  The current approach is racy and that was deemed
sufficient as the oom_reaper is considered a best effort approach to
help with oom handling when the OOM victim cannot terminate in a
reasonable time.  The race could lead to missing an oom victim which can
get stuck

out_of_memory
  wake_oom_reaper
    cmpxchg // OK
    			oom_reaper
			  oom_reap_task
			    __oom_reap_task
oom_victim terminates
			      atomic_inc_not_zero // fail
out_of_memory
  wake_oom_reaper
    cmpxchg // fails
			  task_to_reap = NULL

This race requires 2 OOM invocations in a short time period which is not
very likely but certainly not impossible.  E.g.  the original victim
might have not released a lot of memory for some reason.

The situation would improve considerably if wake_oom_reaper used a more
robust queuing.  This is what this patch implements.  This means adding
oom_reaper_list list_head into task_struct (eat a hole before embeded
thread_struct for that purpose) and a oom_reaper_lock spinlock for
queuing synchronization.  wake_oom_reaper will then add the task on the
queue and oom_reaper will dequeue it.
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Andrea Argangeli <andrea@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Inform about the successful/failed oom_reaper attempts and dump all the
held locks to tell us more who is blocking the progress.

[akpm@linux-foundation.org: fix CONFIG_MMU=n build]
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Andrea Argangeli <andrea@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When oom_reaper manages to unmap all the eligible vmas there shouldn't
be much of the freable memory held by the oom victim left anymore so it
makes sense to clear the TIF_MEMDIE flag for the victim and allow the
OOM killer to select another task.

The lack of TIF_MEMDIE also means that the victim cannot access memory
reserves anymore but that shouldn't be a problem because it would get
the access again if it needs to allocate and hits the OOM killer again
due to the fatal_signal_pending resp.  PF_EXITING check.  We can safely
hide the task from the OOM killer because it is clearly not a good
candidate anymore as everyhing reclaimable has been torn down already.

This patch will allow to cap the time an OOM victim can keep TIF_MEMDIE
and thus hold off further global OOM killer actions granted the oom
reaper is able to take mmap_sem for the associated mm struct.  This is
not guaranteed now but further steps should make sure that mmap_sem for
write should be blocked killable which will help to reduce such a lock
contention.  This is not done by this patch.

Note that exit_oom_victim might be called on a remote task from
__oom_reap_task now so we have to check and clear the flag atomically
otherwise we might race and underflow oom_victims or wake up waiters too
early.
Signed-off-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
Suggested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Andrea Argangeli <andrea@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This patch (of 5):

This is based on the idea from Mel Gorman discussed during LSFMM 2015
and independently brought up by Oleg Nesterov.

The OOM killer currently allows to kill only a single task in a good
hope that the task will terminate in a reasonable time and frees up its
memory.  Such a task (oom victim) will get an access to memory reserves
via mark_oom_victim to allow a forward progress should there be a need
for additional memory during exit path.

It has been shown (e.g.  by Tetsuo Handa) that it is not that hard to
construct workloads which break the core assumption mentioned above and
the OOM victim might take unbounded amount of time to exit because it
might be blocked in the uninterruptible state waiting for an event (e.g.
lock) which is blocked by another task looping in the page allocator.

This patch reduces the probability of such a lockup by introducing a
specialized kernel thread (oom_reaper) which tries to reclaim additional
memory by preemptively reaping the anonymous or swapped out memory owned
by the oom victim under an assumption that such a memory won't be needed
when its owner is killed and kicked from the userspace anyway.  There is
one notable exception to this, though, if the OOM victim was in the
process of coredumping the result would be incomplete.  This is
considered a reasonable constrain because the overall system health is
more important than debugability of a particular application.

A kernel thread has been chosen because we need a reliable way of
invocation so workqueue context is not appropriate because all the
workers might be busy (e.g.  allocating memory).  Kswapd which sounds
like another good fit is not appropriate as well because it might get
blocked on locks during reclaim as well.

oom_reaper has to take mmap_sem on the target task for reading so the
solution is not 100% because the semaphore might be held or blocked for
write but the probability is reduced considerably wrt.  basically any
lock blocking forward progress as described above.  In order to prevent
from blocking on the lock without any forward progress we are using only
a trylock and retry 10 times with a short sleep in between.  Users of
mmap_sem which need it for write should be carefully reviewed to use
_killable waiting as much as possible and reduce allocations requests
done with the lock held to absolute minimum to reduce the risk even
further.

The API between oom killer and oom reaper is quite trivial.
wake_oom_reaper updates mm_to_reap with cmpxchg to guarantee only
NULL->mm transition and oom_reaper clear this atomically once it is done
with the work.  This means that only a single mm_struct can be reaped at
the time.  As the operation is potentially disruptive we are trying to
limit it to the ncessary minimum and the reaper blocks any updates while
it operates on an mm.  mm_struct is pinned by mm_count to allow parallel
exit_mmap and a race is detected by atomic_inc_not_zero(mm_users).
Signed-off-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Suggested-by: Mel Gorman <mgorman@suse.de>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Argangeli <andrea@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This will be needed in the patch "mm, oom: introduce oom reaper".
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Ingo Molnar <mingo@elte.hu>
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 reverts commit e7223f18.

It causes problems when a ppdev tries to register before the parport
driver has been registered with the device model. That will trigger the

        BUG_ON(!drv->bus->p);

at drivers/base/driver.c:153. The call chain is

  kernel_init ->
    kernel_init_freeable ->
      do_one_initcall ->
        ppdev_init ->
          __parport_register_driver ->
            driver_register *BOOM*
Reported-by: kernel test robot <fengguang.wu@intel.com>
Reported-by: Ross Zwisler <zwisler@gmail.com>
Reported-by: Petr Mladek <pmladek@suse.com>
Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull firewire leftover from Stefan Richter:
 "Occurrences of timeval were supposed to be eliminated last round, now
  remove a last forgotten one"

* tag 'firewire-update2' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394:
  firewire: nosy: Replace timeval with timespec64

Pull drm fixes from Dave Airlie:
 "Just a couple of dma-buf related fixes and some amdgpu fixes, along
  with a regression fix for radeon off but default feature, but makes my
  30" monitor happy again"

* 'drm-next' of git://people.freedesktop.org/~airlied/linux:
  drm/radeon/mst: cleanup code indentation
  drm/radeon/mst: fix regression in lane/link handling.
  drm/amdgpu: add invalidate_page callback for userptrs
  drm/amdgpu: Revert "remove the userptr rmn->lock"
  drm/amdgpu: clean up path handling for powerplay
  drm/amd/powerplay: fix memory leak of tdp_table
  dma-buf/fence: fix fence_is_later v2
  dma-buf: Update docs for SYNC ioctl
  drm: remove excess description
  dma-buf, drm, ion: Propagate error code from dma_buf_start_cpu_access()
  drm/atmel-hlcdc: use helper to get crtc state
  drm/atomic: use helper to get crtc state

Pull asm-generic updates from Arnd Bergmann:
 "There are only three patches this time, most other changes to files in
  include/asm-generic tend to go through the tree of whoever depends on
  the change.

  Two patches are cleanups for stuff that is no longer needed, the main
  change is to adapt the generic version of BUG_ON() for CONFIG_BUG=n to
  make it behave consistently with BUG().

  This avoids undefined behavior along with a number of warnings about
  that undefined behavior in randconfig builds when we keep going on
  after hitting a BUG_ON()"

* tag 'asm-generic-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
  asm-generic: remove old nonatomic-io wrapper files
  asm-generic: default BUG_ON(x) to if(x)BUG()
  asm-generic: page.h: Remove useless get_user_page and free_user_page

some amd fixes
* 'drm-next-4.6' of git://people.freedesktop.org/~agd5f/linux:
  drm/radeon/mst: cleanup code indentation
  drm/radeon/mst: fix regression in lane/link handling.
  drm/amdgpu: add invalidate_page callback for userptrs
  drm/amdgpu: Revert "remove the userptr rmn->lock"
  drm/amdgpu: clean up path handling for powerplay
  drm/amd/powerplay: fix memory leak of tdp_table

Pull more power management and ACPI updates from Rafael Wysocki:
 "The second batch of power management and ACPI updates for v4.6.

  Included are fixups on top of the previous PM/ACPI pull request and
  other material that didn't make into it but still should go into 4.6.

  Among other things, there's a fix for an intel_pstate driver issue
  uncovered by recent cpufreq changes, a workaround for a boot hang on
  Skylake-H related to the handling of deep C-states by the platform and
  a PCI/ACPI fix for the handling of IO port resources on non-x86
  architectures plus some new device IDs and similar.

  Specifics:

   - Fix for an intel_pstate driver issue related to the handling of MSR
     updates uncovered by the recent cpufreq rework (Rafael Wysocki).

   - cpufreq core cleanups related to starting governors and frequency
     synchronization during resume from system suspend and a locking fix
     for cpufreq_quick_get() (Rafael Wysocki, Richard Cochran).

   - acpi-cpufreq and powernv cpufreq driver updates (Jisheng Zhang,
     Michael Neuling, Richard Cochran, Shilpasri Bhat).

   - intel_idle driver update preventing some Skylake-H systems from
     hanging during initialization by disabling deep C-states mishandled
     by the platform in the problematic configurations (Len Brown).

   - Intel Xeon Phi Processor x200 support for intel_idle
     (Dasaratharaman Chandramouli).

   - cpuidle menu governor updates to make it always honor PM QoS
     latency constraints (and prevent C1 from being used as the fallback
     C-state on x86 when they are set below its exit latency) and to
     restore the previous behavior to fall back to C1 if the next timer
     event is set far enough in the future that was changed in 4.4 which
     led to an energy consumption regression (Rik van Riel, Rafael
     Wysocki).

   - New device ID for a future AMD UART controller in the ACPI driver
     for AMD SoCs (Wang Hongcheng).

   - Rockchip rk3399 support for the rockchip-io-domain adaptive voltage
     scaling (AVS) driver (David Wu).

   - ACPI PCI resources management fix for the handling of IO space
     resources on architectures where the IO space is memory mapped
     (IA64 and ARM64) broken by the introduction of common ACPI
     resources parsing for PCI host bridges in 4.4 (Lorenzo Pieralisi).

   - Fix for the ACPI backend of the generic device properties API to
     make it parse non-device (data node only) children of an ACPI
     device correctly (Irina Tirdea).

   - Fixes for the handling of global suspend flags (introduced in 4.4)
     during hibernation and resume from it (Lukas Wunner).

   - Support for obtaining configuration information from Device Trees
     in the PM clocks framework (Jon Hunter).

   - ACPI _DSM helper code and devfreq framework cleanups (Colin Ian
     King, Geert Uytterhoeven)"

* tag 'pm+acpi-4.6-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (23 commits)
  PM / AVS: rockchip-io: add io selectors and supplies for rk3399
  intel_idle: Support for Intel Xeon Phi Processor x200 Product Family
  intel_idle: prevent SKL-H boot failure when C8+C9+C10 enabled
  ACPI / PM: Runtime resume devices when waking from hibernate
  PM / sleep: Clear pm_suspend_global_flags upon hibernate
  cpufreq: governor: Always schedule work on the CPU running update
  cpufreq: Always update current frequency before startig governor
  cpufreq: Introduce cpufreq_update_current_freq()
  cpufreq: Introduce cpufreq_start_governor()
  cpufreq: powernv: Add sysfs attributes to show throttle stats
  cpufreq: acpi-cpufreq: make Intel/AMD MSR access, io port access static
  PCI: ACPI: IA64: fix IO port generic range check
  ACPI / util: cast data to u64 before shifting to fix sign extension
  cpufreq: powernv: Define per_cpu chip pointer to optimize hot-path
  cpuidle: menu: Fall back to polling if next timer event is near
  cpufreq: acpi-cpufreq: Clean up hot plug notifier callback
  intel_pstate: Do not call wrmsrl_on_cpu() with disabled interrupts
  cpufreq: Make cpufreq_quick_get() safe to call
  ACPI / property: fix data node parsing in acpi_get_next_subnode()
  ACPI / APD: Add device HID for future AMD UART controller
  ...

Pull more RTC updates from Alexandre Belloni:
 "A second pull request for v4.6 with a few fixesi before -rc1.  The new
  features for abx80x actually make the RTC behave correctly.

  Drivers:
   - abx80x: handle both XT and RC oscillators, XT failure bit and
     autocalibration
   - m41t80: avoid out of range year values
   - rv8803: workaround an i2c HW issue"

* tag 'rtc-4.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux:
  rtc: abx80x: handle the oscillator failure bit
  rtc: abx80x: handle autocalibration
  rtc: rv8803: workaround i2c HW issue
  rtc: mcp795: add devicetree support
  rtc: asm9260: remove incorrect __init/__exit annotations
  rtc: m41t80: avoid out of range year values
  rtc: s3c: Don't print an error on probe deferral
  rtc: rv3029: stop mentioning rv3029c2

Merge tag 'hwmon-for-linus-v4.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull more hwmon updates from Guenter Roeck:
 "Update hwmon mailing list and web page"

* tag 'hwmon-for-linus-v4.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  MAINTAINERS: Update mailing list and web page for hwmon subsystem

Pull block fixes from Jens Axboe:
 "Final round of fixes for this merge window - some of this has come up
  after the initial pull request, and some of it was put in a post-merge
  branch before the merge window.

  This contains:

   - Fix for a bad check for an error on dma mapping in the mtip32xx
     driver, from Alexey Khoroshilov.

   - A set of fixes for lightnvm, from Javier, Matias, and Wenwei.

   - An NVMe completion record corruption fix from Marta, ensuring that
     we read things in the right order.

   - Two writeback fixes from Tejun, marked for stable@ as well.

   - A blk-mq sw queue iterator fix from Thomas, fixing an oops for
     sparse CPU maps.  They hit this in the hot plug/unplug rework"

* 'for-linus' of git://git.kernel.dk/linux-block:
  nvme: avoid cqe corruption when update at the same time as read
  writeback, cgroup: fix use of the wrong bdi_writeback which mismatches the inode
  writeback, cgroup: fix premature wb_put() in locked_inode_to_wb_and_lock_list()
  blk-mq: Use proper cpumask iterator
  mtip32xx: fix checks for dma mapping errors
  lightnvm: do not load L2P table if not supported
  lightnvm: do not reserve lun on l2p loading
  nvme: lightnvm: return ppa completion status
  lightnvm: add a bitmap of luns
  lightnvm: specify target's logical address area
  null_blk: add lightnvm null_blk device to the nullb_list

Pull MTD updates from Brian Norris:
 "NAND:
   - Add sunxi_nand randomizer support
   - begin refactoring NAND ecclayout structs
   - fix pxa3xx_nand dmaengine usage
   - brcmnand: fix support for v7.1 controller
   - add Qualcomm NAND controller driver

  SPI NOR:
   - add new ls1021a, ls2080a support to Freescale QuadSPI
   - add new flash ID entries
   - support bottom-block protection for Winbond flash
   - support Status Register Write Protect
   - remove broken QPI support for Micron SPI flash

  JFFS2:
   - improve post-mount CRC scan efficiency

  General:
   - refactor bcm63xxpart parser, to later extend for NAND
   - add writebuf size parameter to mtdram

  Other minor code quality improvements"

* tag 'for-linus-20160324' of git://git.infradead.org/linux-mtd: (72 commits)
  mtd: nand: remove kerneldoc for removed function parameter
  mtd: nand: Qualcomm NAND controller driver
  dt/bindings: qcom_nandc: Add DT bindings
  mtd: nand: don't select chip in nand_chip's block_bad op
  mtd: spi-nor: support lock/unlock for a few Winbond chips
  mtd: spi-nor: add TB (Top/Bottom) protect support
  mtd: spi-nor: add SPI_NOR_HAS_LOCK flag
  mtd: spi-nor: use BIT() for flash_info flags
  mtd: spi-nor: disallow further writes to SR if WP# is low
  mtd: spi-nor: make lock/unlock bounds checks more obvious and robust
  mtd: spi-nor: silently drop lock/unlock for already locked/unlocked region
  mtd: spi-nor: wait for SR_WIP to clear on initial unlock
  mtd: nand: simplify nand_bch_init() usage
  mtd: mtdswap: remove useless if (!mtd->ecclayout) test
  mtd: create an mtd_oobavail() helper and make use of it
  mtd: kill the ecclayout->oobavail field
  mtd: nand: check status before reporting timeout
  mtd: bcm63xxpart: give width specifier an 'int', not 'size_t'
  mtd: mtdram: Add parameter for setting writebuf size
  mtd: nand: pxa3xx_nand: kill unused field 'drcmr_cmd'
  ...

Pull UBI/UBIFS updates from Richard Weinberger:
 "This contains cleanups and a maintainer update for UBI and UBIFS"

* tag 'upstream-4.6-rc1' of git://git.infradead.org/linux-ubifs:
  ubifs: Remove unused header
  MAINTAINERS: Update UBIFS entry
  mtd: ubi: Add logging functions ubi_msg, ubi_warn and ubi_err
  ubifs: Add logging functions for ubifs_msg, ubifs_err and ubifs_warn

Pull more nfsd updates from Bruce Fields:
 "Apologies for the previous request, which omitted the top 8 commits
  from my for-next branch (including the SCSI layout commits).  Thanks
  to Trond for spotting my error!"

This actually includes the new layout types, so here's that part of
the pull message repeated:

 "Support for a new pnfs layout type from Christoph Hellwig.  The new
  layout type is a variant of the block layout which uses SCSI features
  to offer improved fencing and device identification.

  Note this pull request also includes the client side of SCSI layout,
  with Trond's permission"

* tag 'nfsd-4.6-1' of git://linux-nfs.org/~bfields/linux:
  nfsd: use short read as well as i_size to set eof
  nfsd: better layoutupdate bounds-checking
  nfsd: block and scsi layout drivers need to depend on CONFIG_BLOCK
  nfsd: add SCSI layout support
  nfsd: move some blocklayout code
  nfsd: add a new config option for the block layout driver
  nfs/blocklayout: add SCSI layout support
  nfs4.h: add SCSI layout definitions

Pull kbuild misc updates from Michal Marek:
 "The non-critical part of kbuild for v4.6-rc1:

   - coccinelle cleanup and a new patch
   - make tags rule for kprobe helpers
   - make rpm fix to avoid spurious grub2 entries
   - make rpm support for %postun script (Fedora only at the moment)"

* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild/mkspec: clean boot loader configuration on rpm removal
  kbuild/mkspec: fix grub2 installkernel issue
  Coccinelle: Add api/setup_timer.cocci
  coccinelle: bugon: reduce rule applicability
  Coccinelle: pm_runtime: reduce rule applicability
  Coccinelle: array_size: reduce rule applicability
  Coccinelle: reduce rule applicability
  scripts/tags.sh: add regex to map kprobe helpers
  scripts/coccinelle: modernize &

Pull kconfig updates from Michal Marek:
 "Just two kconfig commits this time:

   - kconfig Makefile fix for make 3.80

   - Fix calculating symbols so that KCONFIG_ALLCONFIG=... does not
     disable CONFIG_MODULES silently"

* 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  unbreak allmodconfig KCONFIG_ALLCONFIG=...
  scripts/kconfig: allow building with make 3.80 again

Pull kbuild updates from Michal Marek:

 - make dtbs_install fix

 - Error handling fix fixdep and link-vmlinux.sh

 - __UNIQUE_ID fix for clang

 - Fix for if_changed_* to suppress the "is up to date." message

 - The kernel is built with -Werror=incompatible-pointer-types

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild: Add option to turn incompatible pointer check into error
  kbuild: suppress annoying "... is up to date." message
  kbuild: fixdep: Check fstat(2) return value
  scripts/link-vmlinux.sh: force error on kallsyms failure
  Kbuild: provide a __UNIQUE_ID for clang
  dtbsinstall: don't move target directory out of the way

Pull parisc updates from Helge Deller:
 "This patchset adds stack usage debug info for parisc and metag (on
  both the stack grows upwards), switches to the new generic realative
  extable search and sort routines, drops the long time ago removed
  syscalls alloc_hugepages and free_hugepages and wires up the new
  preadv2 and pwritev2 syscalls"

* 'parisc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Wire up preadv2 and pwritev2 syscalls
  parisc: Use generic extable search and sort routines
  parisc: Panic immediately when panic_on_oops
  parisc,metag: Implement CONFIG_DEBUG_STACK_USAGE option
  parisc: Drop alloc_hugepages and free_hugepages syscalls

Pull second set of arm64 updates from Catalin Marinas:

 - KASLR bug fixes: use callee-saved register, boot-time I-cache
   maintenance

 - inv_entry asm macro fix (EL0 check typo)

 - pr_notice("Virtual kernel memory layout...") splitting

 - Clean-ups: use p?d_set_huge consistently, allow preemption around
   copy_to_user_page, remove unused __local_flush_icache_all()

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: mm: allow preemption in copy_to_user_page
  arm64: consistently use p?d_set_huge
  arm64: kaslr: use callee saved register to preserve SCTLR across C call
  arm64: Split pr_notice("Virtual kernel memory layout...") into multiple pr_cont()
  arm64: drop unused __local_flush_icache_all()
  arm64: fix KASLR boot-time I-cache maintenance
  arm64/kernel: fix incorrect EL0 check in inv_entry macro

Pull more ARM DT changes from Arnd Bergmann:
 "Here are some final updates for ARM SoC specific dts files:

   - The i.MX changes were sent relatively late, and had a dependency on
     the clk tree, so I delayed that a bit.  Support for the new i.MX6qp
     SoC and a couple of new boards is added in this branch.

   - Uniphier renames a few files to match the final product names that
     were decided by the company, kudos to the kernel developer(s) for
     getting support upstream before the product release.  Also two
     boards are added.  The patches were posted early enough and nice
     overall, but we forgot to apply them and decided to give it some
     more time in linux-next

   - at91 has two small bug fixes"

* tag 'armsoc-dt2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (83 commits)
  ARM: dts: at91: sama5d4 Xplained: don't disable hsmci regulator
  ARM: dts: at91: sama5d3 Xplained: don't disable hsmci regulator
  ARM: dts: uniphier: add pinmux node for I2C ch4
  ARM: dts: uniphier: add @{address} to EEPROM node
  ARM: dts: uniphier: add PH1-Pro4 Sanji board support
  ARM: dts: uniphier: add PH1-Pro4 Ace board support
  ARM: dts: uniphier: enable I2C channel 2 of ProXstream2 Gentil board
  ARM: dts: uniphier: add EEPROM node for ProXstream2 Gentil board
  ARM: dts: uniphier: add reference clock nodes
  ARM: dts: uniphier: rework UniPhier System Bus nodes
  ARM: dts: uniphier: factor out ranges property of support card
  arm64: dts: uniphier: rename PH1-LD10 to PH1-LD20
  ARM: dts: imx53-qsb: Fix gpio button polarity
  ARM: dts: vfxxx: Add DAC node for Vybrid SoC
  ARM: dts: imx6q: add missing links between ipu2 and mipi dsi
  ARM: dts: imx: Add support for Advantech/GE B850v3
  ARM: dts: imx: Add support for Advantech/GE B650v3
  ARM: dts: imx: Add support for Advantech/GE B450v3
  ARM: dts: imx: Add support for Advantech/GE Bx50v3
  ARM: dts: imx: Add Advantech BA-16 Qseven module
  ...

Pull h8300 updates from Yoshinori Sato:
 "Various h8300 fixes"

* tag 'for-4.6' of git://git.osdn.jp/gitroot/uclinux-h8/linux:
  h8300: switch EARLYCON
  h8300: dts: Rename the serial port clock to fck

Handle the Oscillator Failure ('OF') bit from Oscillator Status register
(0x1D). This bit is cleared on set_time function and is read each time the
date/time is read, but only in case of XT Oscillator selection.
In RC mode, this bit is always set.
Signed-off-by: Mylène Josserand <mylene.josserand@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

The autocalibration is separated in two bits to set in Oscillator
Control register (0x1c) :
 - OSEL bit to select the oscillator type (XT or RC).
 - ACAL bit to select the autocalibration type.

These functionnalities are exported in sysfs entries : "oscillator"
and "autocalibration". Respectively, the values are "xtal" for XT
oscillator and "rc" for RC oscillator and 0 to disable the
autocalibration cycle, 512 for a 512 seconds autocalibration cycle
and 1024 for a cycle of 1024 seconds.

Examples :
Set to XT Oscillator
echo xtal > /sys/class/rtc/rtc0/device/oscillator
Activate an autocalibration every 512 seconds
echo 512 > /sys/class/rtc/rtc0/device/autocalibration
Signed-off-by: Mylène Josserand <mylene.josserand@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

The rv8803 has a 60µs window where it will not answer on the i2c bus.
It also means there will be no ack for the communication. Make sure
communication is tried multiple times when this happens (the i2c subsystem
mandates -ENXIO is that case but the number of retries is host specific).
The critical parts are the probe function and the alarm callback so make
sure we handle the failure there.

Cc: stable@vger.kernel.org # v4.4
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

* acpi-soc:
  ACPI / APD: Add device HID for future AMD UART controller

* acpi-misc:
  ACPI / util: cast data to u64 before shifting to fix sign extension

* acpi-pci:
  PCI: ACPI: IA64: fix IO port generic range check

* device-properties:
  ACPI / property: fix data node parsing in acpi_get_next_subnode()

* pm-avs:
  PM / AVS: rockchip-io: add io selectors and supplies for rk3399

* pm-clk:
  PM / clk: Add support for obtaining clocks from device-tree

* pm-devfreq:
  PM / devfreq: Spelling s/frequnecy/frequency/

* pm-sleep:
  ACPI / PM: Runtime resume devices when waking from hibernate
  PM / sleep: Clear pm_suspend_global_flags upon hibernate

* pm-cpufreq:
  cpufreq: governor: Always schedule work on the CPU running update
  cpufreq: Always update current frequency before startig governor
  cpufreq: Introduce cpufreq_update_current_freq()
  cpufreq: Introduce cpufreq_start_governor()
  cpufreq: powernv: Add sysfs attributes to show throttle stats
  cpufreq: acpi-cpufreq: make Intel/AMD MSR access, io port access static
  cpufreq: powernv: Define per_cpu chip pointer to optimize hot-path
  cpufreq: acpi-cpufreq: Clean up hot plug notifier callback
  intel_pstate: Do not call wrmsrl_on_cpu() with disabled interrupts
  cpufreq: Make cpufreq_quick_get() safe to call

* pm-cpuidle:
  intel_idle: Support for Intel Xeon Phi Processor x200 Product Family
  intel_idle: prevent SKL-H boot failure when C8+C9+C10 enabled
  cpuidle: menu: Fall back to polling if next timer event is near
  cpuidle: menu: use high confidence factors only when considering polling

The old web page for the hwmon subsystem is no longer operational,
and the mailing list has become unreliable. Move both to kernel.org.
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

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
  ...

Pull thermal updates from Zhang Rui:

 - Fix a regression where bogus trip points on some Lenovo laptops start
   to screw up thermal control after commit 81ad4276 ("Thermal:
   initialize thermal zone device correctly").

   On these Lenovo laptops, a bogus passive trip point is reported,
   which is 0 degree Celsius.  Without commit 81ad4276, thermal zone
   fails to set cooling devices to proper cooling state, which is a bug.
   But with commit 81ad4276 applied, the processors are always
   throttled on these Lenovo laptops because the current temperature is
   always higher than the passive trip point.

   Fix things to ignore such bogus trip points.  (Zhang Rui)

 - Introduce Mediatek thermal driver.  (Sascha Hauer)

 - Introduce devm_ versions of OF thermal sensor register API.  (Laxman
   Dewangan)

 - Changes in Kconfigs to allow compile test on UM arch.  (Krzysztof
   Kozlowski)

 - Introduce Skylake support in intel_pch_thermal driver.  (Srinivas
   Pandruvada)

 - Several small fixes on Rockchip, TI-SoC, Tegra, RCar, and Exynos
   thermal drivers.

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux: (26 commits)
  Thermal: Ignore invalid trip points
  thermal: trace: migrating thermal traces to use TRACE_DEFINE_ENUM() macros
  thermal: intel_pch_thermal: Enable Skylake PCH thermal
  thermal: doc: Add details of devm_thermal_zone_of_sensor_{register,unregister}
  thermal: of-thermal: Add devm version of thermal_zone_of_sensor_register
  thermal: doc: Add details of thermal_zone_of_sensor_{register,unregister}
  thermal: exynos: Defer probe if vtmu is present but not registered
  thermal: exynos: Use devm_regulator_get_optional() for vtmu
  thermal: exynos: List vtmu-supply as optional property in DT binding
  thermal: exynos: Print a message about exceeded number of supported trip-points
  thermal: exynos: Document number of supported trip-points
  thermal: exynos: Document compatible for Exynos5433 TMU
  thermal: mtk: allow compile testing on UM
  thermal: tegra_soctherm: fix sign bit of temperature
  thermal: Fix build error of missing devm_ioremap_resource on UM
  thermal: ti-soc-thermal: clean up the error handling a bit
  thermal: rcar: Use ARCH_RENESAS
  thermal: rcar_thermal: don't open code of_device_get_match_data()
  thermal: db8500_cpufreq_cooling: Compile with COMPILE_TEST
  thermal: rockchip: fix the tsadc sequence output on rk3228/rk3399
  ...

Pull nfsd updates from Bruce Fields:
 "Various bugfixes, a RDMA update from Chuck Lever, and support for a
  new pnfs layout type from Christoph Hellwig.  The new layout type is a
  variant of the block layout which uses SCSI features to offer improved
  fencing and device identification.

  (Also: note this pull request also includes the client side of SCSI
  layout, with Trond's permission.)"

* tag 'nfsd-4.6' of git://linux-nfs.org/~bfields/linux:
  sunrpc/cache: drop reference when sunrpc_cache_pipe_upcall() detects a race
  nfsd: recover: fix memory leak
  nfsd: fix deadlock secinfo+readdir compound
  nfsd4: resfh unused in nfsd4_secinfo
  svcrdma: Use new CQ API for RPC-over-RDMA server send CQs
  svcrdma: Use new CQ API for RPC-over-RDMA server receive CQs
  svcrdma: Remove close_out exit path
  svcrdma: Hook up the logic to return ERR_CHUNK
  svcrdma: Use correct XID in error replies
  svcrdma: Make RDMA_ERROR messages work
  rpcrdma: Add RPCRDMA_HDRLEN_ERR
  svcrdma: svc_rdma_post_recv() should close connection on error
  svcrdma: Close connection when a send error occurs
  nfsd: Lower NFSv4.1 callback message size limit
  svcrdma: Do not send Write chunk XDR pad with inline content
  svcrdma: Do not write xdr_buf::tail in a Write chunk
  svcrdma: Find client-provided write and reply chunks once per reply
  nfsd: Update NFS server comments related to RDMA support
  nfsd: Fix a memory leak when meeting unsupported state_protect_how4
  nfsd4: fix bad bounds checking

Pull staging driver fixes from Greg KH:
 "Here are some fixes that poped up due to the big staging tree merge,
  as well as the removal of a staging driver that now is covered by a
  "real" driver.

  All of these have been in linux-next for a few days with no reported
  issues"

* tag 'staging-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: delete STE RMI4 hackish driver
  staging: android: ion_test: fix check of platform_device_register_simple() error code
  staging: wilc1000: fix a couple of memory leaks
  staging: fsl-mc: fix incorrect type passed to dev_err macros
  staging: fsl-mc: fix incorrect type passed to dev_dbg macros
  staging: wilc1000: fixed kernel panic when firmware is not started
  staging: comedi: ni_mio_common: fix the ni_write[blw]() functions
  staging: most: hdm-dim2: Remove possible dereference error
  staging: lustre: checking for NULL instead of IS_ERR
  staging: lustre: really make lustre dependent on LNet
  staging: refresh TODO for rtl8712
  staging: refresh TODO for rtl8723au

Pull timer fix from Thomas Gleixner:
 "A single fix to the pistachio clocksource driver using the proper
  signedness in the error print format"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource/drivers/pistachio: Correct output format of PTR_ERR()

Pull irq fixes from Thomas Gleixner:
 "A small set of fixes for the usual ARM/SOC irqchip drivers

   - A set of fixes for mbigen to handle multiple devices in a hardware
     module proper

   - A cleanup for the mbigen config option which was pointlessly user
     configurable.

   - A cleanup for tegra replacing open coded functionality by the
     proper core function

  The config cleanup touches arch/arm64/Kconfig.platforms to select the
  irq chip for the related platform"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/mbigen: Make CONFIG_HISILICON_IRQ_MBIGEN a hidden option
  ARM64: Kconfig: Select mbigen interrupt controller on Hisilicon platform
  irqchip/mbigen: Handle multiple device nodes in a mbigen module
  irqchip/mbigen: Adjust DT bindings to handle multiple devices in a module
  irqchip/tegra: Switch to use irq_domain_free_irqs_common

Pull perf fixes from Ingo Molnar:
 "This tree contains various perf fixes on the kernel side, plus three
  hw/event-enablement late additions:

   - Intel Memory Bandwidth Monitoring events and handling
   - the AMD Accumulated Power Mechanism reporting facility
   - more IOMMU events

  ... and a final round of perf tooling updates/fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits)
  perf llvm: Use strerror_r instead of the thread unsafe strerror one
  perf llvm: Use realpath to canonicalize paths
  perf tools: Unexport some methods unused outside strbuf.c
  perf probe: No need to use formatting strbuf method
  perf help: Use asprintf instead of adhoc equivalents
  perf tools: Remove unused perf_pathdup, xstrdup functions
  perf tools: Do not include stringify.h from the kernel sources
  tools include: Copy linux/stringify.h from the kernel
  tools lib traceevent: Remove redundant CPU output
  perf tools: Remove needless 'extern' from function prototypes
  perf tools: Simplify die() mechanism
  perf tools: Remove unused DIE_IF macro
  perf script: Remove lots of unused arguments
  perf thread: Rename perf_event__preprocess_sample_addr to thread__resolve
  perf machine: Rename perf_event__preprocess_sample to machine__resolve
  perf tools: Add cpumode to struct perf_sample
  perf tests: Forward the perf_sample in the dwarf unwind test
  perf tools: Remove misplaced __maybe_unused
  perf list: Fix documentation of :ppp
  perf bench numa: Fix assertion for nodes bitfield
  ...

Merge tag 'at91-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nferre/linux-at91 into next/dt2

Merge "First fixes batch for AT91 on 4.6 - DT only fixes" from Nicolas Ferre:
- prevent the boards from having glitches when inserting/removing SD card on
  sama5d3/d4 Xplained. The regulators should be kept on.

* tag 'at91-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nferre/linux-at91:
  ARM: dts: at91: sama5d4 Xplained: don't disable hsmci regulator
  ARM: dts: at91: sama5d3 Xplained: don't disable hsmci regulator
  ARM: dts: at91: sama5d2 Xplained: add leds node
  ARM: dts: at91: sama5d2 Xplained: add user push button
  ARM: dts: at91: sama5d2 Xplained: set pin muxing for usb gadget and usb host
  ARM: dts: at91: sama5d2: add nand0 and nfc0 nodes
  ARM: dts: at91: sama5d2: add dma properties to UART nodes
  ARM: dts: at91: sama5d2 Xplained: Correct the macb irq pinctrl node