openwrt/staging/blogic.git
8 years agodrivers/pinctrl/intel/pinctrl-baytrail.c: fix build with gcc-4.4
Andrew Morton [Thu, 26 May 2016 22:16:30 +0000 (15:16 -0700)]
drivers/pinctrl/intel/pinctrl-baytrail.c: fix build with gcc-4.4

gcc-4.4 and thereabouts has issues with initializers of anonymous
unions, and it generates the following warnings:

  drivers/pinctrl/intel/pinctrl-baytrail.c:413: error: unknown field 'simple_funcs' specified in initializer
  drivers/pinctrl/intel/pinctrl-baytrail.c:413: warning: missing braces around initializer
  drivers/pinctrl/intel/pinctrl-baytrail.c:413: warning: (near initialization for 'byt_score_groups[0].<anonymous>')
  drivers/pinctrl/intel/pinctrl-baytrail.c:415: error: unknown field 'simple_funcs' specified in initializer
  drivers/pinctrl/intel/pinctrl-baytrail.c:417: error: unknown field 'simple_funcs' specified in initializer
  ...

Work around this.

Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agoupdate "mm/zsmalloc: don't fail if can't create debugfs info"
Dan Streetman [Thu, 26 May 2016 22:16:27 +0000 (15:16 -0700)]
update "mm/zsmalloc: don't fail if can't create debugfs info"

Some updates to commit d34f615720d1 ("mm/zsmalloc: don't fail if can't
create debugfs info"):

 - add pr_warn to all stat failure cases
 - do not prevent module loading on stat failure

Link: http://lkml.kernel.org/r/1463671123-5479-1-git-send-email-ddstreet@ieee.org
Signed-off-by: Dan Streetman <ddstreet@ieee.org>
Reviewed-by: Ganesh Mahendran <opensource.ganesh@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Dan Streetman <dan.streetman@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agodma-debug: avoid spinlock recursion when disabling dma-debug
Ville Syrjälä [Thu, 26 May 2016 22:16:25 +0000 (15:16 -0700)]
dma-debug: avoid spinlock recursion when disabling dma-debug

With netconsole (at least) the pr_err("...  disablingn") call can
recurse back into the dma-debug code, where it'll try to grab
free_entries_lock again.  Avoid the problem by doing the printk after
dropping the lock.

Link: http://lkml.kernel.org/r/1463678421-18683-1-git-send-email-ville.syrjala@linux.intel.com
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agomm: oom_reaper: remove some bloat
Michal Hocko [Thu, 26 May 2016 22:16:22 +0000 (15:16 -0700)]
mm: oom_reaper: remove some bloat

mmput_async is currently used only from the oom_reaper which is defined
only for CONFIG_MMU.  We can save work_struct in mm_struct for
!CONFIG_MMU.

[akpm@linux-foundation.org: fix typo, per Minchan]
Link: http://lkml.kernel.org/r/20160520061658.GB19172@dhcp22.suse.cz
Reported-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Minchan Kim <minchan@kernel.org>
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>
8 years agomemcg: fix mem_cgroup_out_of_memory() return value.
Tetsuo Handa [Thu, 26 May 2016 22:16:19 +0000 (15:16 -0700)]
memcg: fix mem_cgroup_out_of_memory() return value.

mem_cgroup_out_of_memory() is returning "true" if it finds a TIF_MEMDIE
task after an eligible task was found, "false" if it found a TIF_MEMDIE
task before an eligible task is found.

This difference confuses memory_max_write() which checks the return
value of mem_cgroup_out_of_memory().  Since memory_max_write() wants to
continue looping, mem_cgroup_out_of_memory() should return "true" in
this case.

This patch sets a dummy pointer in order to return "true".

Link: http://lkml.kernel.org/r/1463753327-5170-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agoocfs2: fix improper handling of return errno
Eric Ren [Thu, 26 May 2016 22:16:16 +0000 (15:16 -0700)]
ocfs2: fix improper handling of return errno

Previously, if a bad inode was found in ocfs2_iget(), -ESTALE was
returned back to the caller anyway.  Since commit d2b9d71a2da7 ("ocfs2:
check/fix inode block for online file check") can handle with return
value from ocfs2_read_locked_inode() now, we know the exact errno
returned for us.

Link: http://lkml.kernel.org/r/1463970656-18413-1-git-send-email-zren@suse.com
Signed-off-by: Eric Ren <zren@suse.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agomm: slub: remove unused virt_to_obj()
Andrey Ryabinin [Thu, 26 May 2016 22:16:14 +0000 (15:16 -0700)]
mm: slub: remove unused virt_to_obj()

It's unused since commit 7ed2f9e66385 ("mm, kasan: SLAB support")

Link: http://lkml.kernel.org/r/1464020961-2242-1-git-send-email-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agomm: kasan: remove unused 'reserved' field from struct kasan_alloc_meta
Andrey Ryabinin [Thu, 26 May 2016 22:16:11 +0000 (15:16 -0700)]
mm: kasan: remove unused 'reserved' field from struct kasan_alloc_meta

Commit cd11016e5f52 ("mm, kasan: stackdepot implementation.  Enable
stackdepot for SLAB") added 'reserved' field, but never used it.

Link: http://lkml.kernel.org/r/1464021054-2307-1-git-send-email-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agomm: make CONFIG_DEFERRED_STRUCT_PAGE_INIT depends on !FLATMEM explicitly
Yang Shi [Thu, 26 May 2016 22:16:08 +0000 (15:16 -0700)]
mm: make CONFIG_DEFERRED_STRUCT_PAGE_INIT depends on !FLATMEM explicitly

Per the suggestion from Michal Hocko [1], DEFERRED_STRUCT_PAGE_INIT
requires some ordering wrt other initialization operations, e.g.
page_ext_init has to happen after the whole memmap is initialized
properly.

For SPARSEMEM this requires to wait for page_alloc_init_late.  Other
memory models (e.g.  flatmem) might have different initialization
layouts (page_ext_init_flatmem).  Currently DEFERRED_STRUCT_PAGE_INIT
depends on MEMORY_HOTPLUG which in turn

depends on SPARSEMEM || X86_64_ACPI_NUMA
depends on ARCH_ENABLE_MEMORY_HOTPLUG

and X86_64_ACPI_NUMA depends on NUMA which in turn disable FLATMEM
memory model:

config ARCH_FLATMEM_ENABLE
def_bool y
depends on X86_32 && !NUMA

so FLATMEM is ruled out via dependency maze.  Be explicit and disable
FLATMEM for DEFERRED_STRUCT_PAGE_INIT so that we do not reintroduce
subtle initialization bugs

[1] http://lkml.kernel.org/r/20160523073157.GD2278@dhcp22.suse.cz

Link: http://lkml.kernel.org/r/1464027356-32282-1-git-send-email-yang.shi@linaro.org
Signed-off-by: Yang Shi <yang.shi@linaro.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agoseqlock: fix raw_read_seqcount_latch()
Alexey Dobriyan [Thu, 26 May 2016 22:16:06 +0000 (15:16 -0700)]
seqlock: fix raw_read_seqcount_latch()

lockless_dereference() is supposed to take pointer not integer.

Link: http://lkml.kernel.org/r/20160521201448.GA7429@p183.telecom.by
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agoMerge tag 'nfs-for-4.7-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
Linus Torvalds [Thu, 26 May 2016 17:33:33 +0000 (10:33 -0700)]
Merge tag 'nfs-for-4.7-1' of git://git.linux-nfs.org/projects/anna/linux-nfs

Pull NFS client updates from Anna Schumaker:
 "Highlights include:

  Features:
   - Add support for the NFS v4.2 COPY operation
   - Add support for NFS/RDMA over IPv6

  Bugfixes and cleanups:
   - Avoid race that crashes nfs_init_commit()
   - Fix oops in callback path
   - Fix LOCK/OPEN race when unlinking an open file
   - Choose correct stateids when using delegations in setattr, read and
     write
   - Don't send empty SETATTR after OPEN_CREATE
   - xprtrdma: Prevent server from writing a reply into memory client
     has released
   - xprtrdma: Support using Read list and Reply chunk in one RPC call"

* tag 'nfs-for-4.7-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (61 commits)
  pnfs: pnfs_update_layout needs to consider if strict iomode checking is on
  nfs/flexfiles: Use the layout segment for reading unless it a IOMODE_RW and reading is disabled
  nfs/flexfiles: Helper function to detect FF_FLAGS_NO_READ_IO
  nfs: avoid race that crashes nfs_init_commit
  NFS: checking for NULL instead of IS_ERR() in nfs_commit_file()
  pnfs: make pnfs_layout_process more robust
  pnfs: rework LAYOUTGET retry handling
  pnfs: lift retry logic from send_layoutget to pnfs_update_layout
  pnfs: fix bad error handling in send_layoutget
  flexfiles: add kerneldoc header to nfs4_ff_layout_prepare_ds
  flexfiles: remove pointless setting of NFS_LAYOUT_RETURN_REQUESTED
  pnfs: only tear down lsegs that precede seqid in LAYOUTRETURN args
  pnfs: keep track of the return sequence number in pnfs_layout_hdr
  pnfs: record sequence in pnfs_layout_segment when it's created
  pnfs: don't merge new ff lsegs with ones that have LAYOUTRETURN bit set
  pNFS/flexfiles: When initing reads or writes, we might have to retry connecting to DSes
  pNFS/flexfiles: When checking for available DSes, conditionally check for MDS io
  pNFS/flexfile: Fix erroneous fall back to read/write through the MDS
  NFS: Reclaim writes via writepage are opportunistic
  NFSv4: Use the right stateid for delegations in setattr, read and write
  ...

8 years agoMerge tag 'xfs-for-linus-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Thu, 26 May 2016 17:13:40 +0000 (10:13 -0700)]
Merge tag 'xfs-for-linus-4.7-rc1' of git://git./linux/kernel/git/dgc/linux-xfs

Pull xfs updates from Dave Chinner:
 "A pretty average collection of fixes, cleanups and improvements in
  this request.

  Summary:
   - fixes for mount line parsing, sparse warnings, read-only compat
     feature remount behaviour
   - allow fast path symlink lookups for inline symlinks.
   - attribute listing cleanups
   - writeback goes direct to bios rather than indirecting through
     bufferheads
   - transaction allocation cleanup
   - optimised kmem_realloc
   - added configurable error handling for metadata write errors,
     changed default error handling behaviour from "retry forever" to
     "retry until unmount then fail"
   - fixed several inode cluster writeback lookup vs reclaim race
     conditions
   - fixed inode cluster writeback checking wrong inode after lookup
   - fixed bugs where struct xfs_inode freeing wasn't actually RCU safe
   - cleaned up inode reclaim tagging"

* tag 'xfs-for-linus-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (39 commits)
  xfs: fix warning in xfs_finish_page_writeback for non-debug builds
  xfs: move reclaim tagging functions
  xfs: simplify inode reclaim tagging interfaces
  xfs: rename variables in xfs_iflush_cluster for clarity
  xfs: xfs_iflush_cluster has range issues
  xfs: mark reclaimed inodes invalid earlier
  xfs: xfs_inode_free() isn't RCU safe
  xfs: optimise xfs_iext_destroy
  xfs: skip stale inodes in xfs_iflush_cluster
  xfs: fix inode validity check in xfs_iflush_cluster
  xfs: xfs_iflush_cluster fails to abort on error
  xfs: remove xfs_fs_evict_inode()
  xfs: add "fail at unmount" error handling configuration
  xfs: add configuration handlers for specific errors
  xfs: add configuration of error failure speed
  xfs: introduce table-based init for error behaviors
  xfs: add configurable error support to metadata buffers
  xfs: introduce metadata IO error class
  xfs: configurable error behavior via sysfs
  xfs: buffer ->bi_end_io function requires irq-safe lock
  ...

8 years agoMerge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelv...
Linus Torvalds [Thu, 26 May 2016 16:48:23 +0000 (09:48 -0700)]
Merge branch 'hwmon-for-linus' of git://git./linux/kernel/git/jdelvare/staging

Pull hwmon fixlets from Jean Delvare.

* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  Documentation/hwmon: Update links in max34440
  hwmon: (emc2103) Fix typo in MODULE_PARM_DESC

8 years agoMerge tag 'mmc-v4.7-rc1' of git://git.linaro.org/people/ulf.hansson/mmc
Linus Torvalds [Thu, 26 May 2016 16:36:10 +0000 (09:36 -0700)]
Merge tag 'mmc-v4.7-rc1' of git://git.linaro.org/people/ulf.hansson/mmc

Pull MMC fixes from Ulf Hansson:
 "Here are some mmc fixes intended for v4.7 rc1.  They are based on a
  commit earlier in the merge window and have been tested in linux-next
  for a while.

  MMC core:
   - Prevent re-tuning while serving requests for RPMB partitions
   - Extend timeout for long read time quirk to support more eMMCs

  MMC host:
   - sdhci-acpi: Ensure connected devices are powered when probing
   - sdhci-pci|acpi: Remove unreliable MMC_CAP_BUS_WIDTH_TEST for Intel HWs
   - dw_mmc: Correct the assigning of max_blk_size
   - dw_mmc-rockchip: Allow RPMB partitions to be created
   - dw_mmc-rockchip: Set the drive phase properly"

* tag 'mmc-v4.7-rc1' of git://git.linaro.org/people/ulf.hansson/mmc:
  mmc: sdhci-acpi: Remove MMC_CAP_BUS_WIDTH_TEST for Intel controllers
  mmc: sdhci-pci: Remove MMC_CAP_BUS_WIDTH_TEST for Intel controllers
  mmc: longer timeout for long read time quirk
  mmc: dw_mmc: rockchip: Set the drive phase properly
  mmc: dw_mmc: fix the wrong max_blk_size
  mmc: dw_mmc-rockchip: add MMC_CAP_CMD23 capabilities
  mmc: sdhci-acpi: Ensure connected devices are powered when probing
  ACPI / PM: Export acpi_device_fix_up_power()
  mmc: block: Pause re-tuning while switched to the RPMB partition
  mmc: block: Always switch back to main area after RPMB access
  mmc: core: Add a facility to "pause" re-tuning

8 years agoMerge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux
Linus Torvalds [Thu, 26 May 2016 16:23:43 +0000 (09:23 -0700)]
Merge branch 'next' of git://git./linux/kernel/git/rzhang/linux

Pull thermal management updates from Zhang Rui:

 - Introduce generic ADC thermal driver, based on OF thermal (Laxman
   Dewangan)

 - Introduce new thermal driver for Tango chips (Marc Gonzalez)

 - Rockchip driver support for RK3399, RK3366, and some fixes (Caesar
   Wang, Elaine Zhang and Shawn Lin)

 - Add CPU power cooling model to Mediatek thermal driver (Dawei Chien)

 - Wider usage of dev_thermal_zone_of_sensor_register (Eduardo Valentin)

 - TI thermal driver gained a new maintainer (Keerthy).

 - Enabled powerclamp driver by checking CPU feature and package cstate
   counter instead of CPU whitelist (Jacob Pan)

 - Various fixes on thermal governor, OF thermal, Tegra, and RCAR

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux: (50 commits)
  thermal: tango: initialize TEMPSI_CFG
  thermal: rockchip: use the usleep_range instead of udelay
  thermal: rockchip: add the notes for better reading
  thermal: rockchip: Support RK3366 SoCs in the thermal driver
  thermal: rockchip: handle the power sequence for tsadc controller
  thermal: rockchip: update the tsadc table for rk3399
  thermal: rockchip: fixes the code_to_temp for tsadc driver
  thermal: rockchip: disable thermal->clk in err case
  thermal: tegra: add Tegra132 specific SOC_THERM driver
  thermal: fix ptr_ret.cocci warnings
  thermal: mediatek: Add cpu dynamic power cooling model.
  thermal: generic-adc: Add ADC based thermal sensor driver
  thermal: generic-adc: Add DT binding for ADC based thermal sensor
  thermal: tegra: fix static checker warning
  thermal: tegra: mark PM functions __maybe_unused
  thermal: add temperature sensor support for tango SoC
  thermal: hisilicon: fix IRQ imbalance enabling
  thermal: hisilicon: support to use any sensor
  thermal: rcar: Remove binding docs for r8a7794
  thermal: tegra: add PM support
  ...

8 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris...
Linus Torvalds [Thu, 26 May 2016 16:15:19 +0000 (09:15 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/jmorris/linux-security

Pull Yama locking fix from James Morris:
 "Fix for the Yama LSM"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  Yama: fix double-spinlock and user access in atomic context

8 years agopnfs: pnfs_update_layout needs to consider if strict iomode checking is on
Tom Haynes [Wed, 25 May 2016 14:31:14 +0000 (07:31 -0700)]
pnfs: pnfs_update_layout needs to consider if strict iomode checking is on

As flexfiles has FF_FLAGS_NO_READ_IO, there is a need to generically
support enforcing that a IOMODE_RW segment will not allow READ I/O.

Signed-off-by: Tom Haynes <loghyr@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
8 years agonfs/flexfiles: Use the layout segment for reading unless it a IOMODE_RW and reading...
Tom Haynes [Wed, 25 May 2016 14:31:13 +0000 (07:31 -0700)]
nfs/flexfiles: Use the layout segment for reading unless it a IOMODE_RW and reading is disabled

Signed-off-by: Tom Haynes <loghyr@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
8 years agoDocumentation/hwmon: Update links in max34440
Glenn Dayton [Thu, 26 May 2016 09:06:53 +0000 (11:06 +0200)]
Documentation/hwmon: Update links in max34440

It appears the website for maxim-ic.com changed to
maximintegrated.com.

Signed-off-by: Glenn Dayton <glenn.dayton24@gmail.com>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
8 years agohwmon: (emc2103) Fix typo in MODULE_PARM_DESC
Dan Carpenter [Thu, 26 May 2016 09:06:53 +0000 (11:06 +0200)]
hwmon: (emc2103) Fix typo in MODULE_PARM_DESC

"apd" was intended here instead of "init".

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
8 years agoMerge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Thu, 26 May 2016 00:37:33 +0000 (17:37 -0700)]
Merge branch 'x86-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull x86 fixes from Ingo Molnar:
 "Misc fixes: EFI, entry code, pkeys and MPX fixes, TASK_SIZE cleanups
  and a tsc frequency table fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Switch from TASK_SIZE to TASK_SIZE_MAX in the page fault code
  x86/fsgsbase/64: Use TASK_SIZE_MAX for FSBASE/GSBASE upper limits
  x86/mm/mpx: Work around MPX erratum SKD046
  x86/entry/64: Fix stack return address retrieval in thunk
  x86/efi: Fix 7-parameter efi_call()s
  x86/cpufeature, x86/mm/pkeys: Fix broken compile-time disabling of pkeys
  x86/tsc: Add missing Cherrytrail frequency to the table

8 years agoMerge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Thu, 26 May 2016 00:11:43 +0000 (17:11 -0700)]
Merge branch 'sched-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull scheduler fixes from Ingo Molnar:
 "Two fixes: one for a lost wakeup, the other to fix the compiler
  optimizing out preempt operations on ARM64 (and possibly other non-x86
  architectures)"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/core: Fix remote wakeups
  sched/preempt: Fix preempt_count manipulations

8 years agoMerge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Thu, 26 May 2016 00:05:40 +0000 (17:05 -0700)]
Merge branch 'perf-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull perf updates from Ingo Molnar:
 "Mostly tooling and PMU driver fixes, but also a number of late updates
  such as the reworking of the call-chain size limiting logic to make
  call-graph recording more robust, plus tooling side changes for the
  new 'backwards ring-buffer' extension to the perf ring-buffer"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits)
  perf record: Read from backward ring buffer
  perf record: Rename variable to make code clear
  perf record: Prevent reading invalid data in record__mmap_read
  perf evlist: Add API to pause/resume
  perf trace: Use the ptr->name beautifier as default for "filename" args
  perf trace: Use the fd->name beautifier as default for "fd" args
  perf report: Add srcline_from/to branch sort keys
  perf evsel: Record fd into perf_mmap
  perf evsel: Add overwrite attribute and check write_backward
  perf tools: Set buildid dir under symfs when --symfs is provided
  perf trace: Only auto set call-graph to "dwarf" when syscalls are being traced
  perf annotate: Sort list of recognised instructions
  perf annotate: Fix identification of ARM blt and bls instructions
  perf tools: Fix usage of max_stack sysctl
  perf callchain: Stop validating callchains by the max_stack sysctl
  perf trace: Fix exit_group() formatting
  perf top: Use machine->kptr_restrict_warned
  perf trace: Warn when trying to resolve kernel addresses with kptr_restrict=1
  perf machine: Do not bail out if not managing to read ref reloc symbol
  perf/x86/intel/p4: Trival indentation fix, remove space
  ...

8 years agoYama: fix double-spinlock and user access in atomic context
Jann Horn [Sun, 22 May 2016 04:01:34 +0000 (06:01 +0200)]
Yama: fix double-spinlock and user access in atomic context

Commit 8a56038c2aef ("Yama: consolidate error reporting") causes lockups
when someone hits a Yama denial. Call chain:

process_vm_readv -> process_vm_rw -> process_vm_rw_core -> mm_access
-> ptrace_may_access
task_lock(...) is taken
__ptrace_may_access -> security_ptrace_access_check
-> yama_ptrace_access_check -> report_access -> kstrdup_quotable_cmdline
-> get_cmdline -> access_process_vm -> get_task_mm
task_lock(...) is taken again

task_lock(p) just calls spin_lock(&p->alloc_lock), so at this point,
spin_lock() is called on a lock that is already held by the current
process.

Also: Since the alloc_lock is a spinlock, sleeping inside
security_ptrace_access_check hooks is probably not allowed at all? So it's
not even possible to print the cmdline from in there because that might
involve paging in userspace memory.

It would be tempting to rewrite ptrace_may_access() to drop the alloc_lock
before calling the LSM, but even then, ptrace_may_access() itself might be
called from various contexts in which you're not allowed to sleep; for
example, as far as I understand, to be able to hold a reference to another
task, usually an RCU read lock will be taken (see e.g. kcmp() and
get_robust_list()), so that also prohibits sleeping. (And using e.g. FUSE,
a user can cause pagefault handling to take arbitrary amounts of time -
see https://bugs.chromium.org/p/project-zero/issues/detail?id=808.)

Therefore, AFAIK, in order to print the name of a process below
security_ptrace_access_check(), you'd have to either grab a reference to
the mm_struct and defer the access violation reporting or just use the
"comm" value that's stored in kernelspace and accessible without big
complications. (Or you could try to use some kind of atomic remote VM
access that fails if the memory isn't paged in, similar to
copy_from_user_inatomic(), and if necessary fall back to comm, but
that'd be kind of ugly because the comm/cmdline choice would look
pretty random to the user.)

Fix it by deferring reporting of the access violation until current
exits kernelspace the next time.

v2: Don't oops on PTRACE_TRACEME, call report_access under
task_lock(current). Also fix nonsensical comment. And don't use
GPF_ATOMIC for memory allocation with no locks held.
This patch is tested both for ptrace attach and ptrace traceme.

Fixes: 8a56038c2aef ("Yama: consolidate error reporting")
Signed-off-by: Jann Horn <jann@thejh.net>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.l.morris@oracle.com>
8 years agoMerge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Wed, 25 May 2016 23:52:19 +0000 (16:52 -0700)]
Merge branch 'core-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull objtool build fix from Ingo Molnar:
 "An libtool fix for older libelf versions"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Allow building with older libelf

8 years agoMerge branch 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Linus Torvalds [Wed, 25 May 2016 22:59:09 +0000 (15:59 -0700)]
Merge branch 'work.iov_iter' of git://git./linux/kernel/git/viro/vfs

Pull vfs iov_iter regression fix from Al Viro:
 "Fix for braino in 'fold checks into iterate_and_advance()'"

* 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  do "fold checks into iterate_and_advance()" right

8 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Linus Torvalds [Wed, 25 May 2016 22:54:35 +0000 (15:54 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/viro/vfs

Pull vfs xattr regression fixes from Al Viro.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  make xattr_resolve_handlers() safe to use with NULL ->s_xattr
  xattr: Fail with -EINVAL for NULL attribute names

8 years agoMerge tag 'acpi-4.7-rc1-more' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael...
Linus Torvalds [Wed, 25 May 2016 22:38:56 +0000 (15:38 -0700)]
Merge tag 'acpi-4.7-rc1-more' of git://git./linux/kernel/git/rafael/linux-pm

Pull ACPI fix from Rafael Wysocki:
 "Additional ACPI update for v4.7-rc1

  Just one fix for incorrect async_synchronize_cookie() usage in the
  ACPI battery driver (Chris Wilson)"

* tag 'acpi-4.7-rc1-more' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / battery: Correctly serialise with the pending async probe

8 years agoMerge tag 'pm-4.7-rc1-more' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael...
Linus Torvalds [Wed, 25 May 2016 22:29:21 +0000 (15:29 -0700)]
Merge tag 'pm-4.7-rc1-more' of git://git./linux/kernel/git/rafael/linux-pm

Pull more power management updates from Rafael Wysocki:
 "These are two stable-candidate fixes (PM core, cpuidle) and a bunch of
  cpufreq cleanups.

  Specifics:

   - Stable-candidate cpuidle fix to make it check the right variable
     when deciding whether or not to enable interrupts on the local CPU
     so as to avoid enabling iterrupts too early in some cases if the
     system has both coupled and per-core idle states (Daniel Lezcano).

   - Stable-candidate PM core fix to make it handle failures at the
     "late suspend" stage of device suspend consistently for all devices
     regardless of whether or not async suspend/resume is enabled for
     them (Rafael Wysocki).

   - Cleanups in the cpufreq core, the schedutil governor and the
     intel_pstate driver (Rafael Wysocki, Pankaj Gupta, Viresh Kumar)"

* tag 'pm-4.7-rc1-more' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / sleep: Handle failures in device_suspend_late() consistently
  cpufreq: schedutil: Improve prints messages with pr_fmt
  cpuidle: Fix cpuidle_state_is_coupled() argument in cpuidle_enter()
  cpufreq: simplified goto out in cpufreq_register_driver()
  cpufreq: governor: CPUFREQ_GOV_STOP never fails
  cpufreq: governor: CPUFREQ_GOV_POLICY_EXIT never fails
  intel_pstate: Simplify conditional in intel_pstate_set_policy()

8 years agodo "fold checks into iterate_and_advance()" right
Al Viro [Wed, 25 May 2016 21:36:19 +0000 (17:36 -0400)]
do "fold checks into iterate_and_advance()" right

the only case when we should skip the iterate_and_advance() guts
is when nothing's left in the iterator, _not_ just when requested
amount is 0.  Said guts will do nothing in the latter case anyway;
the problem we tried to deal with in the aforementioned commit is
that when there's nothing left *and* the amount requested is 0,
we might end up deferencing one iovec too many; the value we fetch
from there is discarded in that case, but theoretically it might
oops if the iovec array ends exactly at the end of page with the
next page not mapped.

Bailing out on zero size requested had an unexpected side effect -
zero-length segment in the beginning of iovec array ended up
throwing do_loop_readv_writev() into infinite spin; we do not
advance past the empty segment at all.  Reproducer is trivial:
echo '#include <sys/uio.h>' >a.c
echo 'main() {char c; struct iovec v[] = {{&c,0},{&c,1}}; readv(0,v,2);}' >>a.c
cc a.c && ./a.out </proc/uptime

which should end up with the process not hanging.  Probably ought to
go into LTP or xfstests...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
8 years agomake xattr_resolve_handlers() safe to use with NULL ->s_xattr
Al Viro [Wed, 25 May 2016 21:34:41 +0000 (17:34 -0400)]
make xattr_resolve_handlers() safe to use with NULL ->s_xattr

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
8 years agoxattr: Fail with -EINVAL for NULL attribute names
Andreas Gruenbacher [Mon, 9 May 2016 11:28:49 +0000 (13:28 +0200)]
xattr: Fail with -EINVAL for NULL attribute names

Commit 98e9cb57 improved the xattr name checks in xattr_resolve_name but
didn't update the NULL attribute name check appropriately, so NULL
attribute names lead to NULL pointer dereferences.  Turn that into
-EINVAL results instead.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
  fs/xattr.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
8 years agoMerge branch 'acpi-battery'
Rafael J. Wysocki [Wed, 25 May 2016 20:11:28 +0000 (22:11 +0200)]
Merge branch 'acpi-battery'

* acpi-battery:
  ACPI / battery: Correctly serialise with the pending async probe

8 years agoMerge branches 'pm-cpufreq', 'pm-cpuidle' and 'pm-core'
Rafael J. Wysocki [Wed, 25 May 2016 19:54:45 +0000 (21:54 +0200)]
Merge branches 'pm-cpufreq', 'pm-cpuidle' and 'pm-core'

* pm-cpufreq:
  cpufreq: schedutil: Improve prints messages with pr_fmt
  cpufreq: simplified goto out in cpufreq_register_driver()
  cpufreq: governor: CPUFREQ_GOV_STOP never fails
  cpufreq: governor: CPUFREQ_GOV_POLICY_EXIT never fails
  intel_pstate: Simplify conditional in intel_pstate_set_policy()

* pm-cpuidle:
  cpuidle: Fix cpuidle_state_is_coupled() argument in cpuidle_enter()

* pm-core:
  PM / sleep: Handle failures in device_suspend_late() consistently

8 years agoMerge tag 'pwm/for-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry...
Linus Torvalds [Wed, 25 May 2016 17:40:15 +0000 (10:40 -0700)]
Merge tag 'pwm/for-4.7-rc1' of git://git./linux/kernel/git/thierry.reding/linux-pwm

Pull pwm updates from Thierry Reding:
 "This set of changes introduces an atomic API to the PWM subsystem.
  This is influenced by the DRM atomic API that was introduced a while
  back, though it is obviously a lot simpler.  The fundamental idea
  remains the same, though: drivers provide a single callback to
  implement the atomic configuration of a PWM channel.

  As a side-effect the PWM subsystem gains the ability for initial state
  retrieval, so that the logical state mirrors that of the hardware.
  Many use-cases don't care about this, but for others it is essential.

  These new features require changes in all users, which these patches
  take care of.  The core is transitioned to use the atomic callback if
  available and provides a fallback mechanism for other drivers.

  Changes to transition users and drivers to the atomic API are
  postponed to v4.8"

* tag 'pwm/for-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: (30 commits)
  pwm: Add information about polarity, duty cycle and period to debugfs
  pwm: Switch to the atomic API
  pwm: Update documentation
  pwm: Add core infrastructure to allow atomic updates
  pwm: Add hardware readout infrastructure
  pwm: Move the enabled/disabled info into pwm_state
  pwm: Introduce the pwm_state concept
  pwm: Keep PWM state in sync with hardware state
  ARM: Explicitly apply PWM config extracted from pwm_args
  drm: i915: Explicitly apply PWM config extracted from pwm_args
  input: misc: pwm-beeper: Explicitly apply PWM config extracted from pwm_args
  input: misc: max8997: Explicitly apply PWM config extracted from pwm_args
  backlight: lm3630a: explicitly apply PWM config extracted from pwm_args
  backlight: lp855x: Explicitly apply PWM config extracted from pwm_args
  backlight: lp8788: Explicitly apply PWM config extracted from pwm_args
  backlight: pwm_bl: Use pwm_get_args() where appropriate
  fbdev: ssd1307fb: Use pwm_get_args() where appropriate
  regulator: pwm: Use pwm_get_args() where appropriate
  leds: pwm: Use pwm_get_args() where appropriate
  input: misc: max77693: Use pwm_get_args() where appropriate
  ...

8 years agonfs/flexfiles: Helper function to detect FF_FLAGS_NO_READ_IO
Tom Haynes [Wed, 25 May 2016 14:31:12 +0000 (07:31 -0700)]
nfs/flexfiles: Helper function to detect FF_FLAGS_NO_READ_IO

The mds can inform the client not to use the IOMODE_RW layout
segment for doing READs. I.e., it is basically a
IOMODE_WRITE layout segment.

It would do this to not interfere with the WRITEs.

Signed-off-by: Tom Haynes <loghyr@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
8 years agoMerge git://www.linux-watchdog.org/linux-watchdog
Linus Torvalds [Wed, 25 May 2016 17:19:17 +0000 (10:19 -0700)]
Merge git://www.linux-watchdog.org/linux-watchdog

Pull watchdog updates from Wim Van Sebroeck:

 - add support for Fintek F81865 Super-IO chip

 - add support for watchdogs (RWDT and SWDT) found on RCar Gen3 based
   SoCs from Renesas

 - octeon: Handle the FROZEN hot plug notifier actions

 - f71808e_wdt fixes and cleanups

 - some small improvements in code and documentation

* git://www.linux-watchdog.org/linux-watchdog:
  MAINTAINERS: Add file patterns for watchdog device tree bindings
  Documentation: Add ebc-c384_wdt watchdog-parameters.txt entry
  watchdog: shwdt: Use setup_timer()
  watchdog: cpwd: Use setup_timer()
  arm64: defconfig: enable Renesas Watchdog Timer
  watchdog: renesas-wdt: add driver
  watchdog: remove error message when unable to allocate watchdog device
  watchdog: f71808e_wdt: Fix WDTMOUT_STS register read
  watchdog: f71808e_wdt: Fix typo
  watchdog: f71808e_wdt: Add F81865 support
  watchdog: sp5100_tco: properly check for new register layouts
  watchdog: core: Fix circular locking dependency
  watchdog: core: fix trivial typo in a comment
  watchdog: hpwdt: Adjust documentation to match latest kernel module parameters.
  watchdog: imx2_wdt: add external reset support via dt prop
  watchdog: octeon: Handle the FROZEN hot plug notifier actions.
  watchdog: qcom: Report reboot reason

8 years agonfs: avoid race that crashes nfs_init_commit
Weston Andros Adamson [Wed, 25 May 2016 14:07:23 +0000 (10:07 -0400)]
nfs: avoid race that crashes nfs_init_commit

Since the patch "NFS: Allow multiple commit requests in flight per file"
we can run multiple simultaneous commits on the same inode.  This
introduced a race over collecting pages to commit that made it possible
to call nfs_init_commit() with an empty list - which causes crashes like
the one below.

The fix is to catch this race and avoid calling nfs_init_commit and
initiate_commit when there is no work to do.

Here is the crash:

[600522.076832] BUG: unable to handle kernel NULL pointer dereference at 0000000000000040
[600522.078475] IP: [<ffffffffa0479e72>] nfs_init_commit+0x22/0x130 [nfs]
[600522.078745] PGD 4272b1067 PUD 4272cb067 PMD 0
[600522.078972] Oops: 0000 [#1] SMP
[600522.079204] Modules linked in: nfsv3 nfs_layout_flexfiles rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache dcdbas ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw vmw_vsock_vmci_transport vsock bonding ipmi_devintf ipmi_msghandler coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel ppdev vmw_balloon parport_pc parport acpi_cpufreq vmw_vmci i2c_piix4 shpchp nfsd auth_rpcgss nfs_acl lockd grace sunrpc xfs libcrc32c vmwgfx drm_kms_helper ttm drm crc32c_intel serio_raw vmxnet3
[600522.081380]  vmw_pvscsi ata_generic pata_acpi
[600522.081809] CPU: 3 PID: 15667 Comm: /usr/bin/python Not tainted 4.1.9-100.pd.88.el7.x86_64 #1
[600522.082281] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 09/30/2014
[600522.082814] task: ffff8800bbbfa780 ti: ffff88042ae84000 task.ti: ffff88042ae84000
[600522.083378] RIP: 0010:[<ffffffffa0479e72>]  [<ffffffffa0479e72>] nfs_init_commit+0x22/0x130 [nfs]
[600522.083973] RSP: 0018:ffff88042ae87438  EFLAGS: 00010246
[600522.084571] RAX: 0000000000000000 RBX: ffff880003485e40 RCX: ffff88042ae87588
[600522.085188] RDX: 0000000000000000 RSI: ffff88042ae874b0 RDI: ffff880003485e40
[600522.085756] RBP: ffff88042ae87448 R08: ffff880003486010 R09: ffff88042ae874b0
[600522.086332] R10: 0000000000000000 R11: 0000000000000005 R12: ffff88042ae872d0
[600522.086905] R13: ffff88042ae874b0 R14: ffff880003485e40 R15: ffff88042704c840
[600522.087484] FS:  00007f4728ff2740(0000) GS:ffff88043fd80000(0000) knlGS:0000000000000000
[600522.088070] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[600522.088663] CR2: 0000000000000040 CR3: 000000042b6aa000 CR4: 00000000001406e0
[600522.089327] Stack:
[600522.089926]  0000000000000001 ffff88042ae87588 ffff88042ae874f8 ffffffffa04f09fa
[600522.090549]  0000000000017840 0000000000017840 ffff88042ae87588 ffff8803258d9930
[600522.091169]  ffff88042ae87578 ffffffffa0563d80 0000000000000000 ffff88042704c840
[600522.091789] Call Trace:
[600522.092420]  [<ffffffffa04f09fa>] pnfs_generic_commit_pagelist+0x1da/0x320 [nfsv4]
[600522.093052]  [<ffffffffa0563d80>] ? ff_layout_commit_prepare_v3+0x30/0x30 [nfs_layout_flexfiles]
[600522.093696]  [<ffffffffa0562645>] ff_layout_commit_pagelist+0x15/0x20 [nfs_layout_flexfiles]
[600522.094359]  [<ffffffffa047bc78>] nfs_generic_commit_list+0xe8/0x120 [nfs]
[600522.095032]  [<ffffffffa047bd6a>] nfs_commit_inode+0xba/0x110 [nfs]
[600522.095719]  [<ffffffffa046ac54>] nfs_release_page+0x44/0xd0 [nfs]
[600522.096410]  [<ffffffff811a8122>] try_to_release_page+0x32/0x50
[600522.097109]  [<ffffffff811bd4f1>] shrink_page_list+0x961/0xb30
[600522.097812]  [<ffffffff811bdced>] shrink_inactive_list+0x1cd/0x550
[600522.098530]  [<ffffffff811bea65>] shrink_lruvec+0x635/0x840
[600522.099250]  [<ffffffff811bed60>] shrink_zone+0xf0/0x2f0
[600522.099974]  [<ffffffff811bf312>] do_try_to_free_pages+0x192/0x470
[600522.100709]  [<ffffffff811bf6ca>] try_to_free_pages+0xda/0x170
[600522.101464]  [<ffffffff811b2198>] __alloc_pages_nodemask+0x588/0x970
[600522.102235]  [<ffffffff811fbbd5>] alloc_pages_vma+0xb5/0x230
[600522.103000]  [<ffffffff813a1589>] ? cpumask_any_but+0x39/0x50
[600522.103774]  [<ffffffff811d6115>] wp_page_copy.isra.55+0x95/0x490
[600522.104558]  [<ffffffff810e3438>] ? __wake_up+0x48/0x60
[600522.105357]  [<ffffffff811d7d3b>] do_wp_page+0xab/0x4f0
[600522.106137]  [<ffffffff810a1bbb>] ? release_task+0x36b/0x470
[600522.106902]  [<ffffffff8126dbd7>] ? eventfd_ctx_read+0x67/0x1c0
[600522.107659]  [<ffffffff811da2a8>] handle_mm_fault+0xc78/0x1900
[600522.108431]  [<ffffffff81067ef1>] __do_page_fault+0x181/0x420
[600522.109173]  [<ffffffff811446a6>] ? __audit_syscall_exit+0x1e6/0x280
[600522.109893]  [<ffffffff810681c0>] do_page_fault+0x30/0x80
[600522.110594]  [<ffffffff81024f36>] ? syscall_trace_leave+0xc6/0x120
[600522.111288]  [<ffffffff81790a58>] page_fault+0x28/0x30
[600522.111947] Code: 5d c3 0f 1f 80 00 00 00 00 0f 1f 44 00 00 55 4c 8d 87 d0 01 00 00 48 89 e5 53 48 89 fb 48 83 ec 08 4c 8b 0e 49 8b 41 18 4c 39 ce <48> 8b 40 40 4c 8b 50 30 74 24 48 8b 87 d0 01 00 00 48 8b 7e 08
[600522.113343] RIP  [<ffffffffa0479e72>] nfs_init_commit+0x22/0x130 [nfs]
[600522.114003]  RSP <ffff88042ae87438>
[600522.114636] CR2: 0000000000000040

Fixes: af7cf057 (NFS: Allow multiple commit requests in flight per file)
CC: stable@vger.kernel.org
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
8 years agoMerge tag 'vfio-v4.7-rc1' of git://github.com/awilliam/linux-vfio
Linus Torvalds [Wed, 25 May 2016 16:47:26 +0000 (09:47 -0700)]
Merge tag 'vfio-v4.7-rc1' of git://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - Hide INTx on certain known broken devices (Alex Williamson)

 - Additional backdoor reset detection (Alex Williamson)

 - Remove unused iommudata reference (Alexey Kardashevskiy)

 - Use cfg_size to avoid probing extended config space (Alexey
   Kardashevskiy)

* tag 'vfio-v4.7-rc1' of git://github.com/awilliam/linux-vfio:
  vfio_pci: Test for extended capabilities if config space > 256 bytes
  vfio_iommu_spapr_tce: Remove unneeded iommu_group_get_iommudata
  vfio/pci: Add test for BAR restore
  vfio/pci: Hide broken INTx support from user

8 years agoMerge tag 'drm-4.7-rc1-headers-fix' of git://people.freedesktop.org/~airlied/linux
Linus Torvalds [Wed, 25 May 2016 16:37:50 +0000 (09:37 -0700)]
Merge tag 'drm-4.7-rc1-headers-fix' of git://people.freedesktop.org/~airlied/linux

Pull header warning fix from Dave Airlie:
 "Here is the C++ guards warning fix from Arnd"

[ Background: there are 'extern "C" { }' guards in include/uapi for the
  GPU headers.

  They should arguably be wrapped somehow, but as it is they caused
  checkpatch to warn because it would trigger on the 'extern' and think
  it's exporting a function or variable from the kernel to user space.

  This just fixes checkpatch.  Whether we wrap the C++ guards some way
  in the future will be an independent issue. ]

* tag 'drm-4.7-rc1-headers-fix' of git://people.freedesktop.org/~airlied/linux:
  headers_check: don't warn about c++ guards

8 years agoMerge branch 'parisc-4.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller...
Linus Torvalds [Wed, 25 May 2016 16:27:52 +0000 (09:27 -0700)]
Merge branch 'parisc-4.7-1' of git://git./linux/kernel/git/deller/parisc-linux

Pull parisc updates from Helge Deller:

 - Add native high-resolution timing code for sched_clock() and other
   timing functions based on the processor internal cr16 cycle counters

 - Add syscall tracepoint support

 - Add regset support

 - Speed up get_user() and put_user() functions

 - Updated futex.h to match generic implementation (John David Anglin)

 - A few smaller ftrace build fixes

 - Fixed thuge-gen kernel self test to utilize architectured MAP_HUGETLB
   value

 - Added parisc architecture to seccomp_bpf kernel self test

 - Various typo fixes (Andrea Gelmini)

* 'parisc-4.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Whitespace cleanups in unistd.h
  parisc: Use long jump to reach ftrace_return_to_handler()
  parisc: Fix typo in fpudispatch.c
  parisc: Fix typos in eisa_eeprom.h
  parisc: Fix typo in ldcw.h
  parisc: Fix typo in pdc.h
  parisc: Update futex.h to match generic implementation
  parisc: Merge ftrace C-helper and assembler functions into .text.hot section
  selftests/thuge-gen: Use platform specific MAP_HUGETLB value
  parisc: Add native high-resolution sched_clock() implementation
  parisc: Add ARCH_TRACEHOOK and regset support
  parisc: Add 64bit get_user() and put_user() for 32bit kernel
  parisc: Simplify and speed up get_user() and put_user()
  parisc: Add syscall tracepoint support

8 years agoNFS: checking for NULL instead of IS_ERR() in nfs_commit_file()
Dan Carpenter [Mon, 23 May 2016 10:21:01 +0000 (13:21 +0300)]
NFS: checking for NULL instead of IS_ERR() in nfs_commit_file()

nfs_create_request() doesn't return NULL, it returns error pointers.

Fixes: 67911c8f18b5 ('NFS: Add nfs_commit_file()')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
8 years agoparisc: Whitespace cleanups in unistd.h
Helge Deller [Wed, 25 May 2016 13:40:49 +0000 (15:40 +0200)]
parisc: Whitespace cleanups in unistd.h

Clean up whitespaces and mark unused syscalls as such.

Signed-off-by: Helge Deller <deller@gmx.de>
8 years agosched/core: Fix remote wakeups
Peter Zijlstra [Mon, 23 May 2016 09:19:07 +0000 (11:19 +0200)]
sched/core: Fix remote wakeups

Commit:

  b5179ac70de8 ("sched/fair: Prepare to fix fairness problems on migration")

... introduced a bug: Mike Galbraith found that it introduced a
performance regression, while Paul E. McKenney reported lost
wakeups and bisected it to this commit.

The reason is that I mis-read ttwu_queue() such that I assumed any
wakeup that got a remote queue must have had the task migrated.

Since this is not so; we need to transfer this information between
queueing the wakeup and actually doing the wakeup. Use a new
task_struct::sched_flag for this, we already write to
sched_contributes_to_load in the wakeup path so this is a hot and
modified cacheline.

Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reported-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Tested-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Hunter <ahh@google.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ben Segall <bsegall@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul Turner <pjt@google.com>
Cc: Pavan Kondeti <pkondeti@codeaurora.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: byungchul.park@lge.com
Fixes: b5179ac70de8 ("sched/fair: Prepare to fix fairness problems on migration")
Link: http://lkml.kernel.org/r/20160523091907.GD15728@worktop.ger.corp.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
8 years agoMerge tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Linus Torvalds [Tue, 24 May 2016 22:50:58 +0000 (15:50 -0700)]
Merge tag 'armsoc-fixes' of git://git./linux/kernel/git/arm/arm-soc

Pull ARM SoC fixes from Arnd Bergmann:
 "This is a first set of bug fixes on top of what was merged for 4.7.

  Two patches for lpc32xx address a harmless build warning that was just
  introduced, one patch for the mediatek soc driver fixes a warning for
  arm64, and the pxa changes are minor cleanups that should have been
  part of the original pull requests but that I forgot to apply to the
  cleanup-fixes branch earlier"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: lpc32xx: fix NR_IRQS confict
  ARM: lpc32xx: remove legacy irq controller driver
  soc: mtk-pmic-wrap: avoid integer overflow warning
  ARM: pxa: Remove CLK_IS_ROOT
  ARM: pxa: activate pinctrl for device-tree machines

8 years agoMerge tag 'armsoc-late' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Linus Torvalds [Tue, 24 May 2016 22:46:06 +0000 (15:46 -0700)]
Merge tag 'armsoc-late' of git://git./linux/kernel/git/arm/arm-soc

Pull ARM SoC late DT updates from Arnd Bergmann:
 "This is a collection of a few late fixes and other misc stuff that had
  dependencies on things being merged from other trees.

  The Renesas R-Car power domain handling, and the Nvidia Tegra USB
  support both hand notable changes that required changing the DT
  binding in a way that only provides compatibility with old DT blobs on
  new kernels but not vice versa.  As a consequence, the DT changes are
  based on top of the driver changes and are now in this branch.

  For NXP i.MX and Samsung Exynos, the changes in here depend on other
  changes that got merged through the clk maintainer tree"

* tag 'armsoc-late' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (35 commits)
  ARM: dts: exynos: Add support of Bus frequency using VDD_INT for exynos5422-odroidxu3
  ARM: dts: exynos: Add bus nodes using VDD_INT for Exynos542x SoC
  ARM: dts: exynos: Add NoC Probe dt node for Exynos542x SoC
  ARM: dts: exynos: Add support of bus frequency for exynos4412-trats/odroidu3
  ARM: dts: exynos: Expand the voltage range of buck1/3 regulator for exynos4412-odroidu3
  ARM: dts: exynos: Add support of bus frequency using VDD_INT for exynos3250-rinato
  ARM: dts: exynos: Add exynos4412-ppmu-common dtsi to delete duplicate PPMU nodes
  ARM: dts: exynos: Add bus nodes using VDD_MIF for Exynos4210
  ARM: dts: exynos: Add bus nodes using VDD_INT for Exynos4x12
  ARM: dts: exynos: Add bus nodes using VDD_MIF for Exynos4x12
  ARM: dts: exynos: Add bus nodes using VDD_INT for Exynos3250
  ARM: dts: exynos: Add DMC bus frequency for exynos3250-rinato/monk
  ARM: dts: exynos: Add DMC bus node for Exynos3250
  ARM: tegra: Enable XUSB on Nyan
  ARM: tegra: Enable XUSB on Jetson TK1
  ARM: tegra: Enable XUSB on Venice2
  ARM: tegra: Add Tegra124 XUSB controller
  ARM: tegra: Move Tegra124 to the new XUSB pad controller binding
  ARM: dts: r8a7794: Use SYSC "always-on" PM Domain
  ARM: dts: r8a7793: Use SYSC "always-on" PM Domain
  ...

8 years agoMerge tag 'asm-generic-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd...
Linus Torvalds [Tue, 24 May 2016 22:24:37 +0000 (15:24 -0700)]
Merge tag 'asm-generic-4.7' of git://git./linux/kernel/git/arnd/asm-generic

Pull asm-generic cleanup from Arnd Bergmann:
 "I have only one patch for asm-generic in this release, this one is
  from James Hogan and updates the generic system call table for
  renameat2 so we don't need to provide both renameat and renameat2 in
  newly added architectures"

* tag 'asm-generic-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
  asm-generic: Drop renameat syscall from default list

8 years agoMerge tag 'nfsd-4.7' of git://linux-nfs.org/~bfields/linux
Linus Torvalds [Tue, 24 May 2016 21:39:20 +0000 (14:39 -0700)]
Merge tag 'nfsd-4.7' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "A very quiet cycle for nfsd, mainly just an RDMA update from Chuck
  Lever"

* tag 'nfsd-4.7' of git://linux-nfs.org/~bfields/linux:
  sunrpc: fix stripping of padded MIC tokens
  svcrpc: autoload rdma module
  svcrdma: Generalize svc_rdma_xdr_decode_req()
  svcrdma: Eliminate code duplication in svc_rdma_recvfrom()
  svcrdma: Drain QP before freeing svcrdma_xprt
  svcrdma: Post Receives only for forward channel requests
  svcrdma: Remove superfluous line from rdma_read_chunks()
  svcrdma: svc_rdma_put_context() is invoked twice in Send error path
  svcrdma: Do not add XDR padding to xdr_buf page vector
  svcrdma: Support IPv6 with NFS/RDMA
  nfsd: handle seqid wraparound in nfsd4_preprocess_layout_stateid
  Remove unnecessary allocation

8 years agoMerge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso...
Linus Torvalds [Tue, 24 May 2016 19:55:26 +0000 (12:55 -0700)]
Merge tag 'ext4_for_linus' of git://git./linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "Fix a number of bugs, most notably a potential stale data exposure
  after a crash and a potential BUG_ON crash if a file has the data
  journalling flag enabled while it has dirty delayed allocation blocks
  that haven't been written yet.  Also fix a potential crash in the new
  project quota code and a maliciously corrupted file system.

  In addition, fix some DAX-specific bugs, including when there is a
  transient ENOSPC situation and races between writes via direct I/O and
  an mmap'ed segment that could lead to lost I/O.

  Finally the usual set of miscellaneous cleanups"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (23 commits)
  ext4: pre-zero allocated blocks for DAX IO
  ext4: refactor direct IO code
  ext4: fix race in transient ENOSPC detection
  ext4: handle transient ENOSPC properly for DAX
  dax: call get_blocks() with create == 1 for write faults to unwritten extents
  ext4: remove unmeetable inconsisteny check from ext4_find_extent()
  jbd2: remove excess descriptions for handle_s
  ext4: remove unnecessary bio get/put
  ext4: silence UBSAN in ext4_mb_init()
  ext4: address UBSAN warning in mb_find_order_for_block()
  ext4: fix oops on corrupted filesystem
  ext4: fix check of dqget() return value in ext4_ioctl_setproject()
  ext4: clean up error handling when orphan list is corrupted
  ext4: fix hang when processing corrupted orphaned inode list
  ext4: remove trailing \n from ext4_warning/ext4_error calls
  ext4: fix races between changing inode journal mode and ext4_writepages
  ext4: handle unwritten or delalloc buffers before enabling data journaling
  ext4: fix jbd2 handle extension in ext4_ext_truncate_extend_restart()
  ext4: do not ask jbd2 to write data for delalloc buffers
  jbd2: add support for avoiding data writes during transaction commits
  ...

8 years agoARM: lpc32xx: fix NR_IRQS confict
Arnd Bergmann [Thu, 19 May 2016 08:31:31 +0000 (10:31 +0200)]
ARM: lpc32xx: fix NR_IRQS confict

With the change to sparse IRQs, the lpc32xx platform gets a warning about
conflicting macros:

In file included from arch/arm/mach-lpc32xx/irq.c:31:0:
arch/arm/mach-lpc32xx/include/mach/irqs.h:115:0: warning: "NR_IRQS" redefined
 #define NR_IRQS    96
arch/arm/include/asm/irq.h:9:0: note: this is the location of the previous definition
 #define NR_IRQS NR_IRQS_LEGACY

One such instance was in the old irq driver that is now removed by
the previous patch, but any other file including mach/irqs.h still
has the issue. Since none of them use this constant, we can just
remove the old definition.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 8cb17b5ed017 ("irqchip: Add LPC32xx interrupt controller driver")
8 years agoARM: lpc32xx: remove legacy irq controller driver
Vladimir Zapolskiy [Mon, 25 Apr 2016 01:00:44 +0000 (04:00 +0300)]
ARM: lpc32xx: remove legacy irq controller driver

New NXP LPC32xx irq chip driver is used instead of a legacy one.

[this also fixes a harmless build warning about the NR_IRQS redefinition]

Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Acked-by: Sylvain Lemieux <slemieux.tyco@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
8 years agoMerge tag 'spi-v4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Linus Torvalds [Tue, 24 May 2016 18:12:32 +0000 (11:12 -0700)]
Merge tag 'spi-v4.7' of git://git./linux/kernel/git/broonie/spi

Pull spi updates from Mark Brown:
 "Another quiet release for SPI, almost entirely driver specific changes
  with the diffstat dominated by two new drivers which are about two
  thirds of it in terms of lines of code:

   - new drivers for PIC32 standard and SQI controllers
   - the Cadence driver has had runtime PM support added and quite a few
     fixes and cleanups
   - flash-specific accelerated path support now has a feature query
     interface
   - the pxa2xx driver has been moved to use the core DMA mapping support"

* tag 'spi-v4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (48 commits)
  spi: pic32-sqi: Fix linker error, undefined reference to `bad_dma_ops'
  spi: dw-pci: Spelling s/paltforms/platforms/g
  spi: pic32-sqi: Remove pic32_sqi_setup and pic32_sqi_cleanup
  spi: Fix simple typo s/impelment/implement
  spi: rockchip: potential NULL dereference on error
  spi: zynqmp: disable clocks in error paths
  spi: Drop unnecessary dependencies on relaxed I/O accessors
  spi: qup: Add spi_master_put in remove function
  spi: qup: Handle clocks in pm_runtime suspend and resume
  spi: st-ssc4: Fix missing spi_master_put in spi_st_probe error paths
  spi: st-ssc4: Allow compile test build
  spi: omap2-mcspi: Use dma_request_chan() for requesting DMA channel
  spi: davinci: Use dma_request_chan() for requesting DMA channel
  spi: pic32: Fix checking return value of devm_ioremap_resource
  spi: spi-fsl-dspi: Update DT binding documentation
  spi: Drop duplicate code to set master->dev.parent
  spi: pic32: Set proper bits_per_word_mask
  spi: return error if kmap'd buffers passed to spi_map_buf()
  spi: core: add hook flash_read_supported to spi_master
  spi: pic32-sqi: silence array overflow warning
  ...

8 years agoMerge tag 'for-linus-20160523' of git://git.infradead.org/linux-mtd
Linus Torvalds [Tue, 24 May 2016 18:00:20 +0000 (11:00 -0700)]
Merge tag 'for-linus-20160523' of git://git.infradead.org/linux-mtd

Pull MTD updates from Brian Norris:
 "First cycle with Boris as NAND maintainer! Many (most) bullets stolen
  from him.

  Generic:
   - Migrated NAND LED trigger to be a generic MTD trigger

  NAND:
   - Introduction of the "ECC algorithm" concept, to avoid overloading
     the ECC mode field too much more
   - Replaced the nand_ecclayout infrastructure with something a little
     more flexible (finally!) and future proof
   - Rework of the OMAP GPMC and NAND drivers; the TI folks pulled some
     of this into their own tree as well
   - Prepare the sunxi NAND driver to receive DMA support
   - Handle bitflips in erased pages on GPMI revisions that do not
     support this in hardware.

  SPI NOR:
   - Start using the spi_flash_read() API for SPI drivers that support
     it (i.e., SPI drivers with special memory-mapped flash modes)

  And other small scattered improvments"

* tag 'for-linus-20160523' of git://git.infradead.org/linux-mtd: (155 commits)
  mtd: spi-nor: support GigaDevice gd25lq64c
  mtd: nand_bch: fix spelling of "probably"
  mtd: brcmnand: respect ECC algorithm set by NAND subsystem
  gpmi-nand: Handle ECC Errors in erased pages
  Documentation: devicetree: deprecate "soft_bch" nand-ecc-mode value
  mtd: nand: add support for "nand-ecc-algo" DT property
  mtd: mtd: drop NAND_ECC_SOFT_BCH enum value
  mtd: drop support for NAND_ECC_SOFT_BCH as "soft_bch" mapping
  mtd: nand: read ECC algorithm from the new field
  mtd: nand: fsmc: validate ECC setup by checking algorithm directly
  mtd: nand: set ECC algorithm to Hamming on fallback
  staging: mt29f_spinand: set ECC algorithm explicitly
  CRIS v32: nand: set ECC algorithm explicitly
  mtd: nand: atmel: set ECC algorithm explicitly
  mtd: nand: davinci: set ECC algorithm explicitly
  mtd: nand: bf5xx: set ECC algorithm explicitly
  mtd: nand: omap2: Fix high memory dma prefetch transfer
  mtd: nand: omap2: Start dma request before enabling prefetch
  mtd: nandsim: add __init attribute
  mtd: nand: move of_get_nand_xxx() helpers into nand_base.c
  ...

8 years agoMerge tag 'for-linus-4.7-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Tue, 24 May 2016 17:22:34 +0000 (10:22 -0700)]
Merge tag 'for-linus-4.7-rc0-tag' of git://git./linux/kernel/git/xen/tip

Pull xen bug fixes from David Vrabel.

* tag 'for-linus-4.7-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: use same main loop for counting and remapping pages
  xen/events: Don't move disabled irqs
  xen/x86: actually allocate legacy interrupts on PV guests
  Xen: don't warn about 2-byte wchar_t in efi
  xen/gntdev: reduce copy batch size to 16
  xen/x86: don't lose event interrupts

8 years agoMerge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Linus Torvalds [Tue, 24 May 2016 16:46:45 +0000 (09:46 -0700)]
Merge tag 'for_linus' of git://git./linux/kernel/git/mst/vhost

Pull virtio updates from Michael Tsirkin:
 "Looks like a quiet cycle for virtio.  There's a new inorder option for
  the ringtest tool, and a bugfix for balloon for ppc platforms when
  using virtio 1 mode"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  ringtest: pass buf != NULL
  virtio_balloon: fix PFN format for virtio-1
  virtio: add inorder option

8 years agoMerge tag 'nios2-v4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/lftan/nios2
Linus Torvalds [Tue, 24 May 2016 16:41:46 +0000 (09:41 -0700)]
Merge tag 'nios2-v4.7' of git://git./linux/kernel/git/lftan/nios2

Pull nios2 update from Ley Foon Tan:
 - add order-only DTC dependency to %.dtb target
 - fix libgcc location detection

* tag 'nios2-v4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/lftan/nios2:
  nios2: Add order-only DTC dependency to %.dtb target
  nios2: Fix libgcc location detection

8 years agoMerge tag 'microblaze-4.7-rc1' of git://git.monstr.eu/linux-2.6-microblaze
Linus Torvalds [Tue, 24 May 2016 16:19:38 +0000 (09:19 -0700)]
Merge tag 'microblaze-4.7-rc1' of git://git.monstr.eu/linux-2.6-microblaze

Pull Microblaze updates from Michal Simek:

 - Wire-up new syscalls

 - Fix link error

* tag 'microblaze-4.7-rc1' of git://git.monstr.eu/linux-2.6-microblaze:
  microblaze: pci: export isa_io_base to fix link errors
  microblaze: Wire up userfaultfd, membarrier, mlock2 syscalls

8 years agoxen: use same main loop for counting and remapping pages
Juergen Gross [Wed, 18 May 2016 14:44:54 +0000 (16:44 +0200)]
xen: use same main loop for counting and remapping pages

Instead of having two functions for cycling through the E820 map in
order to count to be remapped pages and remap them later, just use one
function with a caller supplied sub-function called for each region to
be processed. This eliminates the possibility of a mismatch between
both loops which showed up in certain configurations.

Suggested-by: Ed Swierk <eswierk@skyportsystems.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
8 years agoxen/events: Don't move disabled irqs
Ross Lagerwall [Tue, 10 May 2016 15:11:00 +0000 (16:11 +0100)]
xen/events: Don't move disabled irqs

Commit ff1e22e7a638 ("xen/events: Mask a moving irq") open-coded
irq_move_irq() but left out checking if the IRQ is disabled. This broke
resuming from suspend since it tries to move a (disabled) irq without
holding the IRQ's desc->lock. Fix it by adding in a check for disabled
IRQs.

The resulting stacktrace was:
kernel BUG at /build/linux-UbQGH5/linux-4.4.0/kernel/irq/migration.c:31!
invalid opcode: 0000 [#1] SMP
Modules linked in: xenfs xen_privcmd ...
CPU: 0 PID: 9 Comm: migration/0 Not tainted 4.4.0-22-generic #39-Ubuntu
Hardware name: Xen HVM domU, BIOS 4.6.1-xs125180 05/04/2016
task: ffff88003d75ee00 ti: ffff88003d7bc000 task.ti: ffff88003d7bc000
RIP: 0010:[<ffffffff810e26e2>]  [<ffffffff810e26e2>] irq_move_masked_irq+0xd2/0xe0
RSP: 0018:ffff88003d7bfc50  EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffff88003d40ba00 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000100 RDI: ffff88003d40bad8
RBP: ffff88003d7bfc68 R08: 0000000000000000 R09: ffff88003d000000
R10: 0000000000000000 R11: 000000000000023c R12: ffff88003d40bad0
R13: ffffffff81f3a4a0 R14: 0000000000000010 R15: 00000000ffffffff
FS:  0000000000000000(0000) GS:ffff88003da00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd4264de624 CR3: 0000000037922000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff88003d40ba38 0000000000000024 0000000000000000 ffff88003d7bfca0
 ffffffff814c8d92 00000010813ef89d 00000000805ea732 0000000000000009
 0000000000000024 ffff88003cc39b80 ffff88003d7bfce0 ffffffff814c8f66
Call Trace:
 [<ffffffff814c8d92>] eoi_pirq+0xb2/0xf0
 [<ffffffff814c8f66>] __startup_pirq+0xe6/0x150
 [<ffffffff814ca659>] xen_irq_resume+0x319/0x360
 [<ffffffff814c7e75>] xen_suspend+0xb5/0x180
 [<ffffffff81120155>] multi_cpu_stop+0xb5/0xe0
 [<ffffffff811200a0>] ? cpu_stop_queue_work+0x80/0x80
 [<ffffffff811203d0>] cpu_stopper_thread+0xb0/0x140
 [<ffffffff810a94e6>] ? finish_task_switch+0x76/0x220
 [<ffffffff810ca731>] ? __raw_callee_save___pv_queued_spin_unlock+0x11/0x20
 [<ffffffff810a3935>] smpboot_thread_fn+0x105/0x160
 [<ffffffff810a3830>] ? sort_range+0x30/0x30
 [<ffffffff810a0588>] kthread+0xd8/0xf0
 [<ffffffff810a04b0>] ? kthread_create_on_node+0x1e0/0x1e0
 [<ffffffff8182568f>] ret_from_fork+0x3f/0x70
 [<ffffffff810a04b0>] ? kthread_create_on_node+0x1e0/0x1e0

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
8 years agoxen/x86: actually allocate legacy interrupts on PV guests
Stefano Stabellini [Wed, 20 Apr 2016 13:15:01 +0000 (14:15 +0100)]
xen/x86: actually allocate legacy interrupts on PV guests

b4ff8389ed14 is incomplete: relies on nr_legacy_irqs() to get the number
of legacy interrupts when actually nr_legacy_irqs() returns 0 after
probe_8259A(). Use NR_IRQS_LEGACY instead.

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
CC: stable@vger.kernel.org
8 years agoXen: don't warn about 2-byte wchar_t in efi
Arnd Bergmann [Wed, 11 May 2016 12:47:59 +0000 (14:47 +0200)]
Xen: don't warn about 2-byte wchar_t in efi

The XEN UEFI code has become available on the ARM architecture
recently, but now causes a link-time warning:

ld: warning: drivers/xen/efi.o uses 2-byte wchar_t yet the output is to use 4-byte wchar_t; use of wchar_t values across objects may fail

This seems harmless, because the efi code only uses 2-byte
characters when interacting with EFI, so we don't pass on those
strings to elsewhere in the system, and we just need to
silence the warning.

It is not clear to me whether we actually need to build the file
with the -fshort-wchar flag, but if we do, then we should also
pass --no-wchar-size-warning to the linker, to avoid the warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Fixes: 37060935dc04 ("ARM64: XEN: Add a function to initialize Xen specific UEFI runtime services")
8 years agoxen/gntdev: reduce copy batch size to 16
David Vrabel [Mon, 9 May 2016 09:59:48 +0000 (10:59 +0100)]
xen/gntdev: reduce copy batch size to 16

IOCTL_GNTDEV_GRANT_COPY batches copy operations to reduce the number
of hypercalls.  The stack is used to avoid a memory allocation in a
hot path. However, a batch size of 24 requires more than 1024 bytes of
stack which in some configurations causes a compiler warning.

    xen/gntdev.c: In function ‘gntdev_ioctl_grant_copy’:
    xen/gntdev.c:949:1: warning: the frame size of 1248 bytes is
    larger than 1024 bytes [-Wframe-larger-than=]

This is a harmless warning as there is still plenty of stack spare,
but people keep trying to "fix" it.  Reduce the batch size to 16 to
reduce stack usage to less than 1024 bytes.  This should have minimal
impact on performance.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
8 years agoxen/x86: don't lose event interrupts
Stefano Stabellini [Sat, 16 Apr 2016 01:23:00 +0000 (18:23 -0700)]
xen/x86: don't lose event interrupts

On slow platforms with unreliable TSC, such as QEMU emulated machines,
it is possible for the kernel to request the next event in the past. In
that case, in the current implementation of xen_vcpuop_clockevent, we
simply return -ETIME. To be precise the Xen returns -ETIME and we pass
it on. However the result of this is a missed event, which simply causes
the kernel to hang.

Instead it is better to always ask the hypervisor for a timer event,
even if the timeout is in the past. That way there are no lost
interrupts and the kernel survives. To do that, remove the
VCPU_SSHOTTMR_future flag.

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Acked-by: Juergen Gross <jgross@suse.com>
8 years agoMerge tag 'perf-core-for-mingo-20160523' of git://git.kernel.org/pub/scm/linux/kernel...
Ingo Molnar [Tue, 24 May 2016 05:40:52 +0000 (07:40 +0200)]
Merge tag 'perf-core-for-mingo-20160523' of git://git./linux/kernel/git/acme/linux into perf/urgent

Pull perf/core improvements from Arnaldo Carvalho de Melo:

User visible changes:

- Add "srcline_from" and "srcline_to" branch sort keys to 'perf top' and
  'perf report' (Andi Kleen)

Infrastructure changes:

- Make 'perf trace' auto-attach fd->name and ptr->name beautifiers based
  on the name of syscall arguments, this way new syscalls that have
  'const char * (path,pathname,filename)' will use the fd->name beautifier
  (vfs_getname perf probe, if in place) and the 'fd->name' (vfs_getname
  or via /proc/PID/fd/) (Arnaldo Carvalho de Melo)

- Infrastructure to read from a ring buffer in backward write mode (Wang Nan)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
8 years agoheaders_check: don't warn about c++ guards
Arnd Bergmann [Wed, 18 May 2016 16:07:29 +0000 (18:07 +0200)]
headers_check: don't warn about c++ guards

A recent addition to the DRM tree for 4.7 added 'extern "C"' guards
for c++ to all the DRM headers, and that now causes warnings
in 'make headers_check':

usr/include/drm/amdgpu_drm.h:38: userspace cannot reference function or variable defined in the kernel
usr/include/drm/drm.h:63: userspace cannot reference function or variable defined in the kernel
usr/include/drm/drm.h:699: userspace cannot reference function or variable defined in the kernel
usr/include/drm/drm_fourcc.h:30: userspace cannot reference function or variable defined in the kernel
usr/include/drm/drm_mode.h:33: userspace cannot reference function or variable defined in the kernel
usr/include/drm/drm_sarea.h:38: userspace cannot reference function or variable defined in the kernel
usr/include/drm/exynos_drm.h:21: userspace cannot reference function or variable defined in the kernel
usr/include/drm/i810_drm.h:7: userspace cannot reference function or variable defined in the kernel

This changes the headers_check.pl script to not warn about this.
I'm listing the merge commit as introducing the problem, because
there are several patches in this branch that each do this for
one file.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 7c10ddf87472 ("Merge branch 'drm-uapi-extern-c-fixes' of https://github.com/evelikov/linux into drm-next")
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
8 years agoMerge branch 'akpm' (patches from Andrew)
Linus Torvalds [Tue, 24 May 2016 02:42:28 +0000 (19:42 -0700)]
Merge branch 'akpm' (patches from Andrew)

Merge yet more updates from Andrew Morton:

 - Oleg's "wait/ptrace: assume __WALL if the child is traced".  It's a
   kernel-based workaround for existing userspace issues.

 - A few hotfixes

 - befs cleanups

 - nilfs2 updates

 - sys_wait() changes

 - kexec updates

 - kdump

 - scripts/gdb updates

 - the last of the MM queue

 - a few other misc things

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (84 commits)
  kgdb: depends on VT
  drm/amdgpu: make amdgpu_mn_get wait for mmap_sem killable
  drm/radeon: make radeon_mn_get wait for mmap_sem killable
  drm/i915: make i915_gem_mmap_ioctl wait for mmap_sem killable
  uprobes: wait for mmap_sem for write killable
  prctl: make PR_SET_THP_DISABLE wait for mmap_sem killable
  exec: make exec path waiting for mmap_sem killable
  aio: make aio_setup_ring killable
  coredump: make coredump_wait wait for mmap_sem for write killable
  vdso: make arch_setup_additional_pages wait for mmap_sem for write killable
  ipc, shm: make shmem attach/detach wait for mmap_sem killable
  mm, fork: make dup_mmap wait for mmap_sem for write killable
  mm, proc: make clear_refs killable
  mm: make vm_brk killable
  mm, elf: handle vm_brk error
  mm, aout: handle vm_brk failures
  mm: make vm_munmap killable
  mm: make vm_mmap killable
  mm: make mmap_sem for write waits killable for mm syscalls
  MAINTAINERS: add co-maintainer for scripts/gdb
  ...

8 years agoMerge tag 'linux-kselftest-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Tue, 24 May 2016 02:37:41 +0000 (19:37 -0700)]
Merge tag 'linux-kselftest-4.7-rc1' of git://git./linux/kernel/git/shuah/linux-kselftest

Pull kselftest updates from Shuah Khan:
 "This update for Kselftest adds:

   - a new ftrace testcase
   - fixes for ftrace and intel_pstate tests"

* tag 'linux-kselftest-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  tools: testing: define the _GNU_SOURCE macro
  kselftests/ftrace: Add a test case for event pid filtering
  kselftests/ftrace: Detect tracefs mount point

8 years agoMerge tag 'trace-v4.7-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt...
Linus Torvalds [Tue, 24 May 2016 02:30:30 +0000 (19:30 -0700)]
Merge tag 'trace-v4.7-3' of git://git./linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "Reviewing the selftest I recently submitted, I realize that the second
  part of it uses my old hack to get the PID of the spawned background
  tasks, which doesn't work for all shells, instead of the common use of
  $!"

* tag 'trace-v4.7-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftracetest: Use proper logic to find process PID

8 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile
Linus Torvalds [Tue, 24 May 2016 02:05:11 +0000 (19:05 -0700)]
Merge git://git./linux/kernel/git/cmetcalf/linux-tile

Pull arch/tile updates from Chris Metcalf:
 "This is an even quieter cycle than usual"

* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
  Fix typo
  Fix typo
  Fix typo
  tile: sort the "select" lines in the TILE/TILEGX configs
  tile: clarify barrier semantics of atomic_add_return
  tile/defconfigs: Remove CONFIG_IPV6_PRIVACY

8 years agoMerge branch 'for-4.7-dw' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata
Linus Torvalds [Tue, 24 May 2016 01:19:21 +0000 (18:19 -0700)]
Merge branch 'for-4.7-dw' of git://git./linux/kernel/git/tj/libata

Pull libata sata_dwc_460ex updates from Tejun Heo:
 "Patches to bring sata_dwc_460ex up to snuff.

  It was a separate pull request because it depends on dmaengine dw
  platform changes which are now in mainline"

* 'for-4.7-dw' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata: (24 commits)
  ata: dwc: add DMADEVICES dependency
  powerpc/4xx: Device tree update for the 460ex DWC SATA
  ata: sata_dwc_460ex: make debug messages neat
  ata: sata_dwc_460ex: supply physical address of FIFO to DMA
  ata: sata_dwc_460ex: use devm_ioremap
  ata: sata_dwc_460ex: tidy up sata_dwc_clear_dmacr()
  ata: sata_dwc_460ex: use readl/writel_relaxed()
  ata: sata_dwc_460ex: switch to new dmaengine_terminate_* API
  ata: sata_dwc_460ex: add __iomem to register base pointer
  ata: sata_dwc_460ex: get rid of incorrect cast
  ata: sata_dwc_460ex: get rid of some pointless casts
  ata: sata_dwc_460ex: remove empty libata callback
  ata: sata_dwc_460ex: correct HOSTDEV{P}_FROM_*() macros
  ata: sata_dwc_460ex: get rid of global data
  ata: sata_dwc_460ex: add phy support
  ata: sata_dwc_460ex: use "dmas" DT property to find dma channel
  ata: sata_dwc_460ex: don't call ata_sff_qc_issue() on DMA commands
  ata: sata_dwc_460ex: skip dma setup for non-dma commands
  ata: sata_dwc_460ex: select only core part of DMA driver
  ata: sata_dwc_460ex: DMA is always a flow controller
  ...

8 years agoMerge branch 'for-4.7-zac' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata
Linus Torvalds [Tue, 24 May 2016 00:53:39 +0000 (17:53 -0700)]
Merge branch 'for-4.7-zac' of git://git./linux/kernel/git/tj/libata

Pull libata ZAC support from Tejun Heo:
 "This contains Zone ATA Command support for Shingled Magnetic Recording
  devices.

  In addition to sending the new commands down to the device, as ZAC
  commands depend on getting a lot of responses from the device, piping
  up responses is beefed up too.  However, it doesn't involve changes to
  libata core mechanism or its interaction with upper layers, so I'm not
  expecting too many fallouts.

  Kudos to Hannes for driving SMR support"

* 'for-4.7-zac' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata: (28 commits)
  libata: support host-aware and host-managed ZAC devices
  libata: support device-managed ZAC devices
  libata: NCQ encapsulation for ZAC MANAGEMENT OUT
  libata: Implement ZBC OUT translation
  libata: implement ZBC IN translation
  libata: fixup ZAC device disabling
  libata-scsi: Generate sense code for disabled devices
  libata-trace: decode subcommands
  libata: Check log page directory before accessing pages
  libata: Add command definitions for NCQ Encapsulation for READ LOG DMA EXT
  libata: Separate out ata_dev_config_ncq_send_recv()
  libata/libsas: Define ATA_CMD_NCQ_NON_DATA
  libsas: enable FPDMA SEND/RECEIVE
  libata: do not attempt to retrieve sense code twice
  libata-scsi: Set information sense field for invalid parameter
  libata-scsi: set bit pointer for sense code information
  libata-scsi: Set field pointer in sense code
  scsi: add scsi_set_sense_field_pointer()
  libata: Implement control mode page to select sense format
  libata-scsi: generate correct ATA pass-through sense
  ...

8 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris...
Linus Torvalds [Tue, 24 May 2016 00:26:27 +0000 (17:26 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/jmorris/linux-security

Pull more security subsystem updates from James Morris:
 "Minor updates for the keys code"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  MAINTAINERS: Update keyrings record and add asymmetric keys record
  lib: asn1_decoder - add MODULE_LICENSE("GPL")
  KEYS: The PKCS#7 test key type should use the secondary keyring

8 years agokgdb: depends on VT
Jiri Slaby [Mon, 23 May 2016 23:26:20 +0000 (16:26 -0700)]
kgdb: depends on VT

With VT=n, the kernel build fails with:

  drivers/built-in.o: In function `kgdboc_pre_exp_handler':
  kgdboc.c:(.text+0x7b5aa): undefined reference to `fg_console'
  kgdboc.c:(.text+0x7b5ce): undefined reference to `vc_cons'
  kgdboc.c:(.text+0x7b5d5): undefined reference to `vc_cons'

kgdboc.o is built when KGDB_SERIAL_CONSOLE is set.  So make
KGDB_SERIAL_CONSOLE depend on HW_CONSOLE which includes those symbols.

Link: http://lkml.kernel.org/r/1459412955-4696-1-git-send-email-jslaby@suse.cz
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-by: "Jim Davis" <jim.epost@gmail.com>
Acked-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agodrm/amdgpu: make amdgpu_mn_get wait for mmap_sem killable
Michal Hocko [Mon, 23 May 2016 23:26:17 +0000 (16:26 -0700)]
drm/amdgpu: make amdgpu_mn_get wait for mmap_sem killable

amdgpu_mn_get which is called during ioct path relies on mmap_sem for
write.  If the waiting task gets killed by the oom killer it would block
oom_reaper from asynchronous address space reclaim and reduce the
chances of timely OOM resolving.  Wait for the lock in the killable mode
and return with EINTR if the task got killed while waiting.

[arnd@arndb.de: use ERR_PTR() to return from amdgpu_mn_get]
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Christian König <christian.koenig@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agodrm/radeon: make radeon_mn_get wait for mmap_sem killable
Michal Hocko [Mon, 23 May 2016 23:26:14 +0000 (16:26 -0700)]
drm/radeon: make radeon_mn_get wait for mmap_sem killable

radeon_mn_get which is called during ioct path relies on mmap_sem for
write.  If the waiting task gets killed by the oom killer it would block
oom_reaper from asynchronous address space reclaim and reduce the
chances of timely OOM resolving.  Wait for the lock in the killable mode
and return with EINTR if the task got killed while waiting.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: David Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agodrm/i915: make i915_gem_mmap_ioctl wait for mmap_sem killable
Michal Hocko [Mon, 23 May 2016 23:26:11 +0000 (16:26 -0700)]
drm/i915: make i915_gem_mmap_ioctl wait for mmap_sem killable

i915_gem_mmap_ioctl relies on mmap_sem for write.  If the waiting task
gets killed by the oom killer it would block oom_reaper from
asynchronous address space reclaim and reduce the chances of timely OOM
resolving.  Wait for the lock in the killable mode and return with EINTR
if the task got killed while waiting.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: David Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agouprobes: wait for mmap_sem for write killable
Michal Hocko [Mon, 23 May 2016 23:26:08 +0000 (16:26 -0700)]
uprobes: wait for mmap_sem for write killable

xol_add_vma needs mmap_sem for write.  If the waiting task gets killed
by the oom killer it would block oom_reaper from asynchronous address
space reclaim and reduce the chances of timely OOM resolving.  Wait for
the lock in the killable mode and return with EINTR if the task got
killed while waiting.

Do not warn in dup_xol_work if __create_xol_area failed due to fatal
signal pending because this is usually considered a kernel issue.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agoprctl: make PR_SET_THP_DISABLE wait for mmap_sem killable
Michal Hocko [Mon, 23 May 2016 23:26:05 +0000 (16:26 -0700)]
prctl: make PR_SET_THP_DISABLE wait for mmap_sem killable

PR_SET_THP_DISABLE requires mmap_sem for write.  If the waiting task
gets killed by the oom killer it would block oom_reaper from
asynchronous address space reclaim and reduce the chances of timely OOM
resolving.  Wait for the lock in the killable mode and return with EINTR
if the task got killed while waiting.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Alex Thorlton <athorlton@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agoexec: make exec path waiting for mmap_sem killable
Michal Hocko [Mon, 23 May 2016 23:26:02 +0000 (16:26 -0700)]
exec: make exec path waiting for mmap_sem killable

setup_arg_pages requires mmap_sem for write.  If the waiting task gets
killed by the oom killer it would block oom_reaper from asynchronous
address space reclaim and reduce the chances of timely OOM resolving.
Wait for the lock in the killable mode and return with EINTR if the task
got killed while waiting.  All the callers are already handling error
path and the fatal signal doesn't need any additional treatment.

The same applies to __bprm_mm_init.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agoaio: make aio_setup_ring killable
Michal Hocko [Mon, 23 May 2016 23:25:59 +0000 (16:25 -0700)]
aio: make aio_setup_ring killable

aio_setup_ring waits for mmap_sem in writable mode.  If the waiting task
gets killed by the oom killer it would block oom_reaper from
asynchronous address space reclaim and reduce the chances of timely OOM
resolving.  Wait for the lock in the killable mode and return with EINTR
if the task got killed while waiting.  This will also expedite the
return to the userspace and do_exit.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Benamin LaHaise <bcrl@kvack.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agocoredump: make coredump_wait wait for mmap_sem for write killable
Michal Hocko [Mon, 23 May 2016 23:25:57 +0000 (16:25 -0700)]
coredump: make coredump_wait wait for mmap_sem for write killable

coredump_wait waits for mmap_sem for write currently which can prevent
oom_reaper to reclaim the oom victims address space asynchronously
because that requires mmap_sem for read.  This might happen if the oom
victim is multi threaded and some thread(s) is holding mmap_sem for read
(e.g.  page fault) and it is stuck in the page allocator while other
thread(s) reached coredump_wait already.

This patch simply uses down_write_killable and bails out with EINTR if
the lock got interrupted by the fatal signal.  do_coredump will return
right away and do_group_exit will take care to zap the whole thread
group.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agovdso: make arch_setup_additional_pages wait for mmap_sem for write killable
Michal Hocko [Mon, 23 May 2016 23:25:54 +0000 (16:25 -0700)]
vdso: make arch_setup_additional_pages wait for mmap_sem for write killable

most architectures are relying on mmap_sem for write in their
arch_setup_additional_pages.  If the waiting task gets killed by the oom
killer it would block oom_reaper from asynchronous address space reclaim
and reduce the chances of timely OOM resolving.  Wait for the lock in
the killable mode and return with EINTR if the task got killed while
waiting.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Andy Lutomirski <luto@amacapital.net> [x86 vdso]
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agoipc, shm: make shmem attach/detach wait for mmap_sem killable
Michal Hocko [Mon, 23 May 2016 23:25:51 +0000 (16:25 -0700)]
ipc, shm: make shmem attach/detach wait for mmap_sem killable

shmat and shmdt rely on mmap_sem for write.  If the waiting task gets
killed by the oom killer it would block oom_reaper from asynchronous
address space reclaim and reduce the chances of timely OOM resolving.
Wait for the lock in the killable mode and return with EINTR if the task
got killed while waiting.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Davidlohr Bueso <dave@stgolabs.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agomm, fork: make dup_mmap wait for mmap_sem for write killable
Michal Hocko [Mon, 23 May 2016 23:25:48 +0000 (16:25 -0700)]
mm, fork: make dup_mmap wait for mmap_sem for write killable

dup_mmap needs to lock current's mm mmap_sem for write.  If the waiting
task gets killed by the oom killer it would block oom_reaper from
asynchronous address space reclaim and reduce the chances of timely OOM
resolving.  Wait for the lock in the killable mode and return with EINTR
if the task got killed while waiting.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agomm, proc: make clear_refs killable
Michal Hocko [Mon, 23 May 2016 23:25:45 +0000 (16:25 -0700)]
mm, proc: make clear_refs killable

CLEAR_REFS_MM_HIWATER_RSS and CLEAR_REFS_SOFT_DIRTY are relying on
mmap_sem for write.  If the waiting task gets killed by the oom killer
and it would operate on the current's mm it would block oom_reaper from
asynchronous address space reclaim and reduce the chances of timely OOM
resolving.  Wait for the lock in the killable mode and return with EINTR
if the task got killed while waiting.  This will also expedite the
return to the userspace and do_exit even if the mm is remote.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Petr Cermak <petrcermak@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agomm: make vm_brk killable
Michal Hocko [Mon, 23 May 2016 23:25:42 +0000 (16:25 -0700)]
mm: make vm_brk killable

Now that all the callers handle vm_brk failure we can change it wait for
mmap_sem killable to help oom_reaper to not get blocked just because
vm_brk gets blocked behind mmap_sem readers.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agomm, elf: handle vm_brk error
Michal Hocko [Mon, 23 May 2016 23:25:39 +0000 (16:25 -0700)]
mm, elf: handle vm_brk error

load_elf_library doesn't handle vm_brk failure although nothing really
indicates it cannot do that because the function is allowed to fail due
to vm_mmap failures already.  This might be not a problem now but later
patch will make vm_brk killable (resp.  mmap_sem for write waiting will
become killable) and so the failure will be more probable.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agomm, aout: handle vm_brk failures
Michal Hocko [Mon, 23 May 2016 23:25:36 +0000 (16:25 -0700)]
mm, aout: handle vm_brk failures

vm_brk is allowed to fail but load_aout_binary simply ignores the error
and happily continues.  I haven't noticed any problem from that in real
life but later patches will make the failure more likely because vm_brk
will become killable (resp.  mmap_sem for write waiting will become
killable) so we should be more careful now.

The error handling should be quite straightforward because there are
calls to vm_mmap which check the error properly already.  The only
notable exception is set_brk which is called after beyond_if label.  But
nothing indicates that we cannot move it above set_binfmt as the two do
not depend on each other and fail before we do set_binfmt and alter
reference counting.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agomm: make vm_munmap killable
Michal Hocko [Mon, 23 May 2016 23:25:33 +0000 (16:25 -0700)]
mm: make vm_munmap killable

Almost all current users of vm_munmap are ignoring the return value and
so they do not handle potential error.  This means that some VMAs might
stay behind.  This patch doesn't try to solve those potential problems.
Quite contrary it adds a new failure mode by using down_write_killable
in vm_munmap.  This should be safer than other failure modes, though,
because the process is guaranteed to die as soon as it leaves the kernel
and exit_mmap will clean the whole address space.

This will help in the OOM conditions when the oom victim might be stuck
waiting for the mmap_sem for write which in turn can block oom_reaper
which relies on the mmap_sem for read to make a forward progress and
reclaim the address space of the victim.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agomm: make vm_mmap killable
Michal Hocko [Mon, 23 May 2016 23:25:30 +0000 (16:25 -0700)]
mm: make vm_mmap killable

All the callers of vm_mmap seem to check for the failure already and
bail out in one way or another on the error which means that we can
change it to use killable version of vm_mmap_pgoff and return -EINTR if
the current task gets killed while waiting for mmap_sem.  This also
means that vm_mmap_pgoff can be killable by default and drop the
additional parameter.

This will help in the OOM conditions when the oom victim might be stuck
waiting for the mmap_sem for write which in turn can block oom_reaper
which relies on the mmap_sem for read to make a forward progress and
reclaim the address space of the victim.

Please note that load_elf_binary is ignoring vm_mmap error for
current->personality & MMAP_PAGE_ZERO case but that shouldn't be a
problem because the address is not used anywhere and we never return to
the userspace if we got killed.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agomm: make mmap_sem for write waits killable for mm syscalls
Michal Hocko [Mon, 23 May 2016 23:25:27 +0000 (16:25 -0700)]
mm: make mmap_sem for write waits killable for mm syscalls

This is a follow up work for oom_reaper [1].  As the async OOM killing
depends on oom_sem for read we would really appreciate if a holder for
write didn't stood in the way.  This patchset is changing many of
down_write calls to be killable to help those cases when the writer is
blocked and waiting for readers to release the lock and so help
__oom_reap_task to process the oom victim.

Most of the patches are really trivial because the lock is help from a
shallow syscall paths where we can return EINTR trivially and allow the
current task to die (note that EINTR will never get to the userspace as
the task has fatal signal pending).  Others seem to be easy as well as
the callers are already handling fatal errors and bail and return to
userspace which should be sufficient to handle the failure gracefully.
I am not familiar with all those code paths so a deeper review is really
appreciated.

As this work is touching more areas which are not directly connected I
have tried to keep the CC list as small as possible and people who I
believed would be familiar are CCed only to the specific patches (all
should have received the cover though).

This patchset is based on linux-next and it depends on
down_write_killable for rw_semaphores which got merged into tip
locking/rwsem branch and it is merged into this next tree.  I guess it
would be easiest to route these patches via mmotm because of the
dependency on the tip tree but if respective maintainers prefer other
way I have no objections.

I haven't covered all the mmap_write(mm->mmap_sem) instances here

  $ git grep "down_write(.*\<mmap_sem\>)" next/master | wc -l
  98
  $ git grep "down_write(.*\<mmap_sem\>)" | wc -l
  62

I have tried to cover those which should be relatively easy to review in
this series because this alone should be a nice improvement.  Other
places can be changed on top.

[0] http://lkml.kernel.org/r/1456752417-9626-1-git-send-email-mhocko@kernel.org
[1] http://lkml.kernel.org/r/1452094975-551-1-git-send-email-mhocko@kernel.org
[2] http://lkml.kernel.org/r/1456750705-7141-1-git-send-email-mhocko@kernel.org

This patch (of 18):

This is the first step in making mmap_sem write waiters killable.  It
focuses on the trivial ones which are taking the lock early after
entering the syscall and they are not changing state before.

Therefore it is very easy to change them to use down_write_killable and
immediately return with -EINTR.  This will allow the waiter to pass away
without blocking the mmap_sem which might be required to make a forward
progress.  E.g.  the oom reaper will need the lock for reading to
dismantle the OOM victim address space.

The only tricky function in this patch is vm_mmap_pgoff which has many
call sites via vm_mmap.  To reduce the risk keep vm_mmap with the
original non-killable semantic for now.

vm_munmap callers do not bother checking the return value so open code
it into the munmap syscall path for now for simplicity.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@suse.de>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agoMAINTAINERS: add co-maintainer for scripts/gdb
Kieran Bingham [Mon, 23 May 2016 23:25:24 +0000 (16:25 -0700)]
MAINTAINERS: add co-maintainer for scripts/gdb

Add myself as a co-maintainer for scripts/gdb supporting Jan Kizka

Link: http://lkml.kernel.org/r/fb5d34ce563f33d2f324f26f592b24ded30032ee.1462865983.git.jan.kiszka@siemens.com
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agoscripts/gdb: decode bytestream on dmesg for Python3
Kieran Bingham [Mon, 23 May 2016 23:25:21 +0000 (16:25 -0700)]
scripts/gdb: decode bytestream on dmesg for Python3

The recent fixes to lx-dmesg, now allow the command to print
successfully on Python3, however the python interpreter wraps the bytes
for each line with a b'<text>' marker.

To remove this, we need to decode the line, where .decode() will default
to 'UTF-8'

Link: http://lkml.kernel.org/r/d67ccf93f2479c94cb3399262b9b796e0dbefcf2.1462865983.git.jan.kiszka@siemens.com
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Acked-by: Dom Cote <buzdelabuz2@gmail.com>
Tested-by: Dom Cote <buzdelabuz2@gmail.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agoscripts/gdb: fix issue with dmesg.py and python 3.X
Dom Cote [Mon, 23 May 2016 23:25:19 +0000 (16:25 -0700)]
scripts/gdb: fix issue with dmesg.py and python 3.X

When built against Python 3, GDB differs in the return type for its
read_memory function, causing the lx-dmesg command to fail.

Now that we have an improved read_16() we can use the new
read_memoryview() abstraction to make lx-dmesg return valid data on both
current Python APIs

Tested with python 3.4 and 2.7
Tested with gdb 7.7

Link: http://lkml.kernel.org/r/28477b727ff7fe3101fd4e426060e8a68317a639.1462865983.git.jan.kiszka@siemens.com
Signed-off-by: Dom Cote <buzdelabuz2+git@gmail.com>
[kieran@bingham.xyz: Adjusted commit log to better reflect code changes]
Tested-by: Kieran Bingham <kieran@bingham.xyz> (Py2.7,Py3.4,GDB10)
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agoscripts/gdb: improve types abstraction for gdb python scripts
Dom Cote [Mon, 23 May 2016 23:25:16 +0000 (16:25 -0700)]
scripts/gdb: improve types abstraction for gdb python scripts

Change the read_u16 function so it accepts both 'str' and 'byte' as type
for the arguments.

When calling read_memory() from gdb API, depending on if it was built
with 2.7 or 3.X, the format used to return the data will differ ( 'str'
for 2.7, and 'byte' for 3.X ).

Add a function read_memoryview() to be able to get a 'memoryview' object
back from read_memory() both with python 2.7 and 3.X .

Tested with python 3.4 and 2.7
Tested with gdb 7.7

Link: http://lkml.kernel.org/r/73621f564503137a002a639d174e4fb35f73f462.1462865983.git.jan.kiszka@siemens.com
Signed-off-by: Dom Cote <buzdelabuz2+git@gmail.com>
Tested-by: Kieran Bingham <kieran@bingham.xyz> (Py2.7,Py3.4,GDB10)
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agoscripts/gdb: add lx_thread_info_by_pid helper
Kieran Bingham [Mon, 23 May 2016 23:25:13 +0000 (16:25 -0700)]
scripts/gdb: add lx_thread_info_by_pid helper

The tasks module already provides helpers to find the task struct by
pid, and the thread_info by task struct; however this is cumbersome to
utilise on the gdb commandline.

Wrap these two functionalities together in an extra single helper to
allow exploring the thread info, from a PID value

Link: http://lkml.kernel.org/r/dadc5667f053ec811eb3e3033d99d937fedbc93b.1462865983.git.jan.kiszka@siemens.com
Signed-off-by: Kieran Bingham <kieran.bingham@linaro.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agoscripts/gdb: add documentation example for radix tree
Kieran Bingham [Mon, 23 May 2016 23:25:10 +0000 (16:25 -0700)]
scripts/gdb: add documentation example for radix tree

Provide a worked example for utilising the lx_radix_tree_lookup function

Link: http://lkml.kernel.org/r/e786008ac5aec4b84198812805b326d718bdeb4b.1462865983.git.jan.kiszka@siemens.com
Signed-off-by: Kieran Bingham <kieran.bingham@linaro.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agoscripts/gdb: add a Radix Tree Parser
Kieran Bingham [Mon, 23 May 2016 23:25:07 +0000 (16:25 -0700)]
scripts/gdb: add a Radix Tree Parser

Linux makes use of the Radix Tree data structure to store pointers
indexed by integer values.  This structure is utilised across many
structures in the kernel including the IRQ descriptor tables, and
several filesystems.

This module provides a method to lookup values from a structure given
its head node.

Usage:

The function lx_radix_tree_lookup, must be given a symbol of type struct
radix_tree_root, and an index into that tree.

The object returned is a generic integer value, and must be cast
correctly to the type based on the storage in the data structure.

For example, to print the irq descriptor in the sparse irq_desc_tree at
index 18, try the following:

 (gdb) print (struct irq_desc)$lx_radix_tree_lookup(irq_desc_tree, 18)

Link: http://lkml.kernel.org/r/d2028c55e50cf95a9b7f8ca0d11885174b0cc709.1462865983.git.jan.kiszka@siemens.com
Signed-off-by: Kieran Bingham <kieran.bingham@linaro.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agoscripts/gdb: cast CPU numbers to integer
Jan Kiszka [Mon, 23 May 2016 23:25:05 +0000 (16:25 -0700)]
scripts/gdb: cast CPU numbers to integer

We won't see more than 2 billion CPUs any time soon, and having cpu_list
return long makes the output of lx-cpus a bit ugly.

Link: http://lkml.kernel.org/r/dcb45c3b0a59e0fd321fa56ff7aa398458c689b3.1462865983.git.jan.kiszka@siemens.com
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8 years agoscripts/gdb: add cpu iterators
Kieran Bingham [Mon, 23 May 2016 23:25:02 +0000 (16:25 -0700)]
scripts/gdb: add cpu iterators

The linux kernel provides macro's for iterating against values from the
cpu_list masks.  By providing some commonly used masks, we can mirror
the kernels helper macros with easy to use generators.

Link: http://lkml.kernel.org/r/d045c6599771ada1999d49612ee30fd2f9acf17f.1462865983.git.jan.kiszka@siemens.com
Signed-off-by: Kieran Bingham <kieran.bingham@linaro.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>