Pull NFS client updates from Trond Myklebust:
 "Highlights include:

  New features:
   - RDMA client backchannel from Chuck
   - Support for NFSv4.2 file CLONE using the btrfs ioctl

  Bugfixes + cleanups:
   - Move socket data receive out of the bottom halves and into a
     workqueue
   - Refactor NFSv4 error handling so synchronous and asynchronous RPC
     handles errors identically.
   - Fix a panic when blocks or object layouts reads return a bad data
     length
   - Fix nfsroot so it can handle a 1024 byte long path.
   - Fix bad usage of page offset in bl_read_pagelist
   - Various NFSv4 callback cleanups+fixes
   - Fix GETATTR bitmap verification
   - Support hexadecimal number for sunrpc debug sysctl files"

* tag 'nfs-for-4.4-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (53 commits)
  Sunrpc: Supports hexadecimal number for sysctl files of sunrpc debug
  nfs: Fix GETATTR bitmap verification
  nfs: Remove unused xdr page offsets in getacl/setacl arguments
  fs/nfs: remove unnecessary new_valid_dev check
  SUNRPC: fix variable type
  NFS: Enable client side NFSv4.1 backchannel to use other transports
  pNFS/flexfiles: Add support for FF_FLAGS_NO_IO_THRU_MDS
  pNFS/flexfiles: When mirrored, retry failed reads by switching mirrors
  SUNRPC: Remove the TCP-only restriction in bc_svc_process()
  svcrdma: Add backward direction service for RPC/RDMA transport
  xprtrdma: Handle incoming backward direction RPC calls
  xprtrdma: Add support for sending backward direction RPC replies
  xprtrdma: Pre-allocate Work Requests for backchannel
  xprtrdma: Pre-allocate backward rpc_rqst and send/receive buffers
  SUNRPC: Abstract backchannel operations
  xprtrdma: Saving IRQs no longer needed for rb_lock
  xprtrdma: Remove reply tasklet
  xprtrdma: Use workqueue to process RPC/RDMA replies
  xprtrdma: Replace send and receive arrays
  xprtrdma: Refactor reply handler error handling
  ...

Pull gfs2 updates from Bob Peterson:
 "Here is a list of patches we've accumulated for GFS2 for the current
  upstream merge window.  There are only six patches this time:

   1. A cleanup patch from Andreas to remove the gl_spin #define in favor
      of its value for the sake of clarity.
   2. A fix from Andy Price to mark the inode dirty during fallocate.
   3. A fix from Andy Price to set s_mode on mount failures to prevent a
      stack trace.
   4  A patch from me to prevent a kernel BUG() in trans_add_meta/trans_add_data
      due to uninitialized storage.
   5. A patch from me to protecting our freeing of the in-core directory
      hash table to prevent double-free.
   6. A fix for a page/block rounding problem that resulted in a metadata
      coherency problem when the block size != page size"

  I've got a lot more patches in various stages of review and testing,
  but I'm afraid they'll have to wait until the next merge window.  So
  next time we're likely to have a lot more"

* tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  GFS2: Fix rgrp end rounding problem for bsize < page size
  GFS2: Protect freeing directory hash table with i_lock spin_lock
  gfs2: Remove gl_spin define
  gfs2: Add missing else in trans_add_meta/data
  GFS2: Set s_mode before parsing mount options
  GFS2: fallocate: do not rely on file_update_time to mark the inode dirty

Pull ext2 fix from Jan Kara:
 "Fix for DAX on ext2"

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  ext2: Add locking for DAX faults

Pull parisc updates from Helge Deller:
 "We have two patches in here:

   - The parisc uapi headers have been screwed up since quite some time.
     This patch fixes some bugs (e.g. endianess not respected in
     compat_semid64_ds) and cleans them up (e.g. uid_t was used instead
     of __kernel_uid_t) so that they can be used by userspace again.
     This patch has been reviewed by Arnd Bergmann and is scheduled for
     stable kernel series.

   - Drop the hpux_stat64 struct from stat.h, we do not support HP-UX
     binaries since kernel 4.0"

* 'parisc-4.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Fixes and cleanups in kernel uapi header files
  parisc: Drop hpux_stat64 struct from stat.h header file

Pull nios2 updates from Ley Foon Tan:

 - nios2: Remove unnecessary #ifdef guards
 - nios2: Switch to generic __xchg()
 - nios2: Fix unused variable warning

* tag 'nios2-v4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/lftan/nios2:
  nios2: Remove unnecessary #ifdef guards
  nios2: Switch to generic __xchg()
  nios2: Fix unused variable warning

Pull xtensa updates from Chris Zankel:

 - fix remaining issues with noMMU cores
 - fix build for cores w/o cache or zero overhead loop options
 - fix boot of secondary cores in SMP configuration
 - add support for DMA to high memory pages
 - add dma_to_phys and phys_to_dma functions.

* tag 'xtensa-20151108' of git://github.com/czankel/xtensa-linux:
  xtensa: implement dma_to_phys and phys_to_dma
  xtensa: support DMA to high memory
  Revert "xtensa: cache inquiry and unaligned cache handling functions"
  xtensa: drop unused sections and remapped reset handlers
  xtensa: fix secondary core boot in SMP
  xtensa: add FORCE_MAX_ZONEORDER to Kconfig
  xtensa: nommu: provide defconfig for de212 on kc705
  xtensa: nommu: xtfpga: add kc705 DTS
  xtensa: add de212 core variant
  xtensa: nommu: select HAVE_FUTEX_CMPXCHG
  xtensa: nommu: fix default memory start address
  xtensa: nommu: provide correct KIO addresses
  xtensa: nommu: fix USER_RING definition
  xtensa: xtfpga: fix integer overflow in TASK_SIZE
  xtensa: fix build for configs without cache options
  xtensa: fixes for configs without loop option

Pull m68knommu/coldfire fix from Greg Ungerer:
 "Only a single patch, fixes brk area setup problem in nommu
  environments"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
  fs/binfmt_elf_fdpic.c: fix brk area overlap with stack on NOMMU

Pull module updates from Rusty Russell:
 "Nothing exciting, minor tweaks and cleanups"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  scripts: [modpost] add new sections to white list
  modpost: Add flag -E for making section mismatches fatal
  params: don't ignore the rest of cmdline if parse_one() fails
  modpost: abort if a module symbol is too long

This patch fixes a bug introduced by commit 7005c3e4. That patch
tries to map a vm range for resource groups, but the calculation
breaks down when the block size is less than the page size.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>

__HAVE_ARCH_MEMMOVE and __HAVE_ARCH_MEMSET are unconditionally defined
for nios2, so there is no need to protect the function definitions of
memmove() and memset().
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Acked-by: NLey Foon Tan <lftan@altera.com>

The generic __xchg() implementation present in asm-generic/cmpxchg.h is
correct on nios2 and even generates the same code. Switch to this generic
implementation to trim down the amount of ad-hoc copies of the code.
Signed-off-by: NMarek Vasut <marex@denx.de>
Acked-by: NLey Foon Tan <lftan@altera.com>

Fix the following compiler splat by adding __maybe_unused annotation to
the variable. Using this particular annotation has the least ugly impact
on the code compared to using ifdeffery.

arch/nios2/kernel/setup.c: In function 'nios2_boot_init':
arch/nios2/kernel/setup.c:107:7: warning: unused variable 'cmdline_passed' [-Wunused-variable]
  char cmdline_passed[COMMAND_LINE_SIZE] = { 0, };
       ^
Signed-off-by: NMarek Vasut <marex@denx.de>
Acked-by: NLey Foon Tan <lftan@altera.com>

Xtensa improvements for 4.4:

- fix remaining issues with noMMU cores;
- fix build for cores w/o cache or zero overhead loop options;
- fix boot of secondary cores in SMP configuration;
- add support for DMA to high memory pages;
- add dma_to_phys and phys_to_dma functions.

This fixes the following build error seen in -next:

  drivers/gpu/drm/nouveau/nvkm/subdev/instmem/gk20a.c:143:2: error:
  implicit declaration of function 'dma_to_phys'
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

- don't bugcheck if high memory page is passed to xtensa_map_page;
- turn empty dcache flush macros into functions so that they could be
  passed as function parameters;
- use kmap_atomic to map high memory pages for cache invalidation/
  flushing performed by xtensa_sync_single_for_{cpu,device}.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

This patch fixes some bugs and partly cleans up the parisc uapi header
files to what glibc defined:
- compat_semid64_ds was wrong and did not take the endianess into
  account
- ipc64_perm exported userspace types which broke building userspace
  packages on debian (e.g. trinity)
- ipc64_perm needs to use a 32bit mode_t on 64bit kernel
- msqid64_ds and semid64_ds needs unsigned longs for various struct members
- shmid64_ds exported size_t instead of __kernel_size_t

And finally add some compile-time checks for the sizes of those structs
to avoid future breakage.

Runtime-tested with the Linux Test Project (LTP) testsuite.

Cc: <stable@vger.kernel.org> # 3.18+
Reviewed-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NHelge Deller <deller@gmx.de>

The struct hpux_stat64 is not needed any longer since we dropped HP-UX
support in commit 04c16149 ("parisc: hpux - Drop support for HP-UX
binaries").
Signed-off-by: NHelge Deller <deller@gmx.de>

__GFP_WAIT was renamed for __GFP_RECLAIM and the gfpflags_allow_blocking()
helper was added.

Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Merge second patch-bomb from Andrew Morton:

 - most of the rest of MM

 - procfs

 - lib/ updates

 - printk updates

 - bitops infrastructure tweaks

 - checkpatch updates

 - nilfs2 update

 - signals

 - various other misc bits: coredump, seqfile, kexec, pidns, zlib, ipc,
   dma-debug, dma-mapping, ...

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (102 commits)
  ipc,msg: drop dst nil validation in copy_msg
  include/linux/zutil.h: fix usage example of zlib_adler32()
  panic: release stale console lock to always get the logbuf printed out
  dma-debug: check nents in dma_sync_sg*
  dma-mapping: tidy up dma_parms default handling
  pidns: fix set/getpriority and ioprio_set/get in PRIO_USER mode
  kexec: use file name as the output message prefix
  fs, seqfile: always allow oom killer
  seq_file: reuse string_escape_str()
  fs/seq_file: use seq_* helpers in seq_hex_dump()
  coredump: change zap_threads() and zap_process() to use for_each_thread()
  coredump: ensure all coredumping tasks have SIGNAL_GROUP_COREDUMP
  signal: remove jffs2_garbage_collect_thread()->allow_signal(SIGCONT)
  signal: introduce kernel_signal_stop() to fix jffs2_garbage_collect_thread()
  signal: turn dequeue_signal_lock() into kernel_dequeue_signal()
  signals: kill block_all_signals() and unblock_all_signals()
  nilfs2: fix gcc uninitialized-variable warnings in powerpc build
  nilfs2: fix gcc unused-but-set-variable warnings
  MAINTAINERS: nilfs2: add header file for tracing
  nilfs2: add tracepoints for analyzing reading and writing metadata files
  ...

Pull rdma updates from Doug Ledford:
 "This is my initial round of 4.4 merge window patches.  There are a few
  other things I wish to get in for 4.4 that aren't in this pull, as
  this represents what has gone through merge/build/run testing and not
  what is the last few items for which testing is not yet complete.

   - "Checksum offload support in user space" enablement
   - Misc cxgb4 fixes, add T6 support
   - Misc usnic fixes
   - 32 bit build warning fixes
   - Misc ocrdma fixes
   - Multicast loopback prevention extension
   - Extend the GID cache to store and return attributes of GIDs
   - Misc iSER updates
   - iSER clustering update
   - Network NameSpace support for rdma CM
   - Work Request cleanup series
   - New Memory Registration API"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma: (76 commits)
  IB/core, cma: Make __attribute_const__ declarations sparse-friendly
  IB/core: Remove old fast registration API
  IB/ipath: Remove fast registration from the code
  IB/hfi1: Remove fast registration from the code
  RDMA/nes: Remove old FRWR API
  IB/qib: Remove old FRWR API
  iw_cxgb4: Remove old FRWR API
  RDMA/cxgb3: Remove old FRWR API
  RDMA/ocrdma: Remove old FRWR API
  IB/mlx4: Remove old FRWR API support
  IB/mlx5: Remove old FRWR API support
  IB/srp: Dont allocate a page vector when using fast_reg
  IB/srp: Remove srp_finish_mapping
  IB/srp: Convert to new registration API
  IB/srp: Split srp_map_sg
  RDS/IW: Convert to new memory registration API
  svcrdma: Port to new memory registration API
  xprtrdma: Port to new memory registration API
  iser-target: Port to new memory registration API
  IB/iser: Port to new fast registration API
  ...

Pull trivial updates from Jiri Kosina:
 "Trivial stuff from trivial tree that can be trivially summed up as:

   - treewide drop of spurious unlikely() before IS_ERR() from Viresh
     Kumar

   - cosmetic fixes (that don't really affect basic functionality of the
     driver) for pktcdvd and bcache, from Julia Lawall and Petr Mladek

   - various comment / printk fixes and updates all over the place"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
  bcache: Really show state of work pending bit
  hwmon: applesmc: fix comment typos
  Kconfig: remove comment about scsi_wait_scan module
  class_find_device: fix reference to argument "match"
  debugfs: document that debugfs_remove*() accepts NULL and error values
  net: Drop unlikely before IS_ERR(_OR_NULL)
  mm: Drop unlikely before IS_ERR(_OR_NULL)
  fs: Drop unlikely before IS_ERR(_OR_NULL)
  drivers: net: Drop unlikely before IS_ERR(_OR_NULL)
  drivers: misc: Drop unlikely before IS_ERR(_OR_NULL)
  UBI: Update comments to reflect UBI_METAONLY flag
  pktcdvd: drop null test before destroy functions

Pull HID updates from Jiri Kosina:
 "Highlights:

   - Intel Skylake Win8 precision touchpads support fixes/improvements
     from Mika Westerberg

   - Lenovo Yoga 2 quirk from Ritesh Raj Sarraf

   - potential uninitialized buffer access fix in HID core from Richard
     Purdie

   - Wacom Intuos and Wacom Cintiq 2 support improvements from Jason
     Gerecke and Ping Cheng

   - initiation of sysfs deprecation process for most of the roccat
     drivers, from the roccat support maintiner Stefan Achatz

   - quite a few device ID / quirk additions and small fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: (30 commits)
  HID: logitech: Add support for G29
  HID: logitech: Simplify wheel detection scheme
  HID: wacom: Call 'wacom_query_tablet_data' only after 'hid_hw_start'
  HID: wacom: Fix ABS_MISC reporting for Cintiq Companion 2
  HID: wacom: Remove useless conditions from 'wacom_query_tablet_data'
  HID: wacom: fix Intuos wireless report id issue
  HID: fix some indenting issues
  HID: wacom: Expect 'touch_max' touches if HID_DG_CONTACTCOUNT not present
  HID: wacom: Tie cached HID_DG_CONTACTCOUNT indices to report ID
  HID: roccat: Fixed resubmit: Deprecating most Roccat sysfs attributes
  HID: wacom: Report full pressure range for Intuos, Cintiq 13HD Touch
  HID: wacom: Add support for Cintiq Companion 2
  HID: multitouch: Fetch feature reports on demand for Win8 devices
  HID: sensor-hub: Add quirk for Lenovo Yoga 2 with ITE Chips
  HID: usbhid: Fix for the WiiU adapter from Mayflash
  HID: corsair: boolify struct k90_led.removed
  HID: corsair: Add Corsair Vengeance K90 driver
  HID: hid-input: allow input_configured callback return errors
  HID: multitouch: Add suffix for HID_DG_TOUCHPAD
  HID: i2c-hid: Fill in physical device providing HID functionality
  ...

Pull livepatching fix from Jiri Kosina:
 "A fix for a kernel oops in case CONFIG_DEBUG_SET_MODULE_RONX is unset
  (as in such case it's possible for module struct to share a page with
  executable text, which is currently not being handled with grace) from
  Josh Poimboeuf"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
  livepatch: Fix crash with !CONFIG_DEBUG_SET_MODULE_RONX

d0edd852 ("ipc: convert invalid scenarios to use WARN_ON") relaxed the
nil dst parameter check, originally being a full BUG_ON.  However, this
check seems quite unnecessary when the only purpose is for
ceckpoint/restore (MSG_COPY flag):

o The copy variable is set initially to nil, apparently as a way of
  ensuring that prepare_copy is previously called.  Which is in fact done,
  unconditionally at the beginning of do_msgrcv.

o There is no concurrency with 'copy' (stack allocated in do_msgrcv).

Furthermore, any errors in 'copy' (and thus prepare_copy/copy_msg) should
always handled by IS_ERR() family.  Therefore remove this check altogether
as it can never occur with the current users.
Signed-off-by: NDavidlohr Bueso <dbueso@suse.de>
Cc: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

alder32 was renamed to zlib_adler32 since before 2.6.11.
Signed-off-by: NAnish Bhatt <anish@chelsio.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In some cases we may end up killing the CPU holding the console lock
while still having valuable data in logbuf. E.g. I'm observing the
following:

- A crash is happening on one CPU and console_unlock() is being called on
  some other.

- console_unlock() tries to print out the buffer before releasing the lock
  and on slow console it takes time.

- in the meanwhile crashing CPU does lots of printk()-s with valuable data
  (which go to the logbuf) and sends IPIs to all other CPUs.

- console_unlock() finishes printing previous chunk and enables interrupts
  before trying to print out the rest, the CPU catches the IPI and never
  releases console lock.

This is not the only possible case: in VT/fb subsystems we have many other
console_lock()/console_unlock() users.  Non-masked interrupts (or
receiving NMI in case of extreme slowness) will have the same result.
Getting the whole console buffer printed out on crash should be top
priority.

[akpm@linux-foundation.org: tweak comment text]
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Baoquan He <bhe@redhat.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Xie XiuQi <xiexiuqi@huawei.com>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Like dma_unmap_sg, dma_sync_sg* should be called with the original number
of entries passed to dma_map_sg, so do the same check in the sync path as
we do in the unmap path.
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Sakari Ailus <sakari.ailus@iki.fi>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Many DMA controllers and other devices set max_segment_size to
indicate their scatter-gather capability, but have no interest in
segment_boundary_mask. However, the existence of a dma_parms structure
precludes the use of any default value, leaving them as zeros (assuming
a properly kzalloc'ed structure). If a well-behaved IOMMU (or SWIOTLB)
then tries to respect this by ensuring a mapped segment does not cross
a zero-byte boundary, hilarity ensues.

Since zero is a nonsensical value for either parameter, treat it as an
indicator for "default", as might be expected. In the process, clean up
a bit by replacing the bare constants with slightly more meaningful
macros and removing the superfluous "else" statements.

[akpm@linux-foundation.org: dma-mapping.h needs sizes.h for SZ_64K]
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Reviewed-by: NSumit Semwal <sumit.semwal@linaro.org>
Acked-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Sakari Ailus <sakari.ailus@iki.fi>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

setpriority(PRIO_USER, 0, x) will change the priority of tasks outside of
the current pid namespace.  This is in contrast to both the other modes of
setpriority and the example of kill(-1).  Fix this.  getpriority and
ioprio have the same failure mode, fix them too.

Eric said:

: After some more thinking about it this patch sounds justifiable.
:
: My goal with namespaces is not to build perfect isolation mechanisms
: as that can get into ill defined territory, but to build well defined
: mechanisms.  And to handle the corner cases so you can use only
: a single namespace with well defined results.
:
: In this case you have found the two interfaces I am aware of that
: identify processes by uid instead of by pid.  Which quite frankly is
: weird.  Unfortunately the weird unexpected cases are hard to handle
: in the usual way.
:
: I was hoping for a little more information.  Changes like this one we
: have to be careful of because someone might be depending on the current
: behavior.  I don't think they are and I do think this make sense as part
: of the pid namespace.
Signed-off-by: NBen Segall <bsegall@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ambrose Feinstein <ambrose@google.com>
Acked-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

kexec output message misses the prefix "kexec", when Dave Young split the
kexec code.  Now, we use file name as the output message prefix.

Currently, the format of output message:
[  140.290795] SYSC_kexec_load: hello, world
[  140.291534] kexec: sanity_check_segment_list: hello, world

Ideally, the format of output message:
[   30.791503] kexec: SYSC_kexec_load, Hello, world
[   79.182752] kexec_core: sanity_check_segment_list, Hello, world

Remove the custom prefix "kexec" in output message.
Signed-off-by: NMinfei Huang <mnfhuang@gmail.com>
Acked-by: NDave Young <dyoung@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since 5cec38ac ("fs, seq_file: fallback to vmalloc instead of oom kill
processes") seq_buf_alloc() avoids calling the oom killer for PAGE_SIZE or
smaller allocations; but larger allocations can use the oom killer via
vmalloc().  Thus reads of small files can return ENOMEM, but larger files
use the oom killer to avoid ENOMEM.

The effect of this bug is that reads from /proc and other virtual
filesystems can return ENOMEM instead of the preferred behavior - oom
killing something (possibly the calling process).  I don't know of anyone
except Google who has noticed the issue.

I suspect the fix is more needed in smaller systems where there isn't any
reclaimable memory.  But these seem like the kinds of systems which
probably don't use the oom killer for production situations.

Memory overcommit requires use of the oom killer to select a victim
regardless of file size.

Enable oom killer for small seq_buf_alloc() allocations.

Fixes: 5cec38ac ("fs, seq_file: fallback to vmalloc instead of oom kill processes")
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NGreg Thelen <gthelen@google.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

strint_escape_str() escapes input string by given criteria.  In case of
seq_escape() the criteria is to convert some characters to their octal
representation.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This improves code readability.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Change zap_threads() paths to use for_each_thread() rather than
while_each_thread().

While at it, change zap_threads() to avoid the nested if's to make the
code more readable and lessen the indentation.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Kyle Walker <kwalker@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Stanislav Kozina <skozina@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

task_will_free_mem() is wrong in many ways, and in particular the
SIGNAL_GROUP_COREDUMP check is not reliable: a task can participate in the
coredumping without SIGNAL_GROUP_COREDUMP bit set.

change zap_threads() paths to always set SIGNAL_GROUP_COREDUMP even if
other CLONE_VM processes can't react to SIGKILL.  Fortunately, at least
oom-kill case if fine; it kills all tasks sharing the same mm, so it
should also kill the process which actually dumps the core.

The change in prepare_signal() is not strictly necessary, it just ensures
that the patch does not bring another subtle behavioural change.  But it
reminds us that this SIGNAL_GROUP_EXIT/COREDUMP case needs more changes.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Kyle Walker <kwalker@redhat.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Cc: Stanislav Kozina <skozina@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

jffs2_garbage_collect_thread() does allow_signal(SIGCONT) for no reason,
SIGCONT will wake a stopped task up even if it is ignored.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Reviewed-by: NTejun Heo <tj@kernel.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

jffs2_garbage_collect_thread() can race with SIGCONT and sleep in
TASK_STOPPED state after it was already sent. Add the new helper,
kernel_signal_stop(), which does this correctly.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Reviewed-by: NTejun Heo <tj@kernel.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

1. Rename dequeue_signal_lock() to kernel_dequeue_signal(). This
   matches another "for kthreads only" kernel_sigaction() helper.

2. Remove the "tsk" and "mask" arguments, they are always current
   and current->blocked. And it is simply wrong if tsk != current.

3. We could also remove the 3rd "siginfo_t *info" arg but it looks
   potentially useful. However we can simplify the callers if we
   change kernel_dequeue_signal() to accept info => NULL.

4. Remove _irqsave, it is never called from atomic context.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Reviewed-by: NTejun Heo <tj@kernel.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It is hardly possible to enumerate all problems with block_all_signals()
and unblock_all_signals().  Just for example,

1. block_all_signals(SIGSTOP/etc) simply can't help if the caller is
   multithreaded. Another thread can dequeue the signal and force the
   group stop.

2. Even is the caller is single-threaded, it will "stop" anyway. It
   will not sleep, but it will spin in kernel space until SIGCONT or
   SIGKILL.

And a lot more. In short, this interface doesn't work at all, at least
the last 10+ years.

Daniel said:

  Yeah the only times I played around with the DRM_LOCK stuff was when
  old drivers accidentally deadlocked - my impression is that the entire
  DRM_LOCK thing was never really tested properly ;-) Hence I'm all for
  purging where this leaks out of the drm subsystem.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Acked-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: NDave Airlie <airlied@redhat.com>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some false positive warnings are reported for powerpc build.

The following warnings are reported in
 http://kisskb.ellerman.id.au/kisskb/buildresult/12519703/

   CC      fs/nilfs2/super.o
 fs/nilfs2/super.c: In function 'nilfs_resize_fs':
 fs/nilfs2/super.c:376:2: warning: 'blocknr' may be used uninitialized in this function [-Wuninitialized]
 fs/nilfs2/super.c:362:11: note: 'blocknr' was declared here
   CC      fs/nilfs2/recovery.o
 fs/nilfs2/recovery.c: In function 'nilfs_salvage_orphan_logs':
 fs/nilfs2/recovery.c:631:21: warning: 'sum' may be used uninitialized in this function [-Wuninitialized]
 fs/nilfs2/recovery.c:585:32: note: 'sum' was declared here
 fs/nilfs2/recovery.c: In function 'nilfs_search_super_root':
 fs/nilfs2/recovery.c:873:11: warning: 'sum' may be used uninitialized in this function [-Wuninitialized]

Another similar warning is reported in
 http://kisskb.ellerman.id.au/kisskb/buildresult/12520079/

   CC      fs/nilfs2/btree.o
 fs/nilfs2/btree.c: In function 'nilfs_btree_convert_and_insert':
 include/asm-generic/bitops/non-atomic.h:105:20: warning: 'bh' may be used uninitialized in this function [-Wuninitialized]
 fs/nilfs2/btree.c:1859:22: note: 'bh' was declared here

This cleans out these warnings by forcing the variables to be initialized.
Signed-off-by: NRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Reported-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>