git commit 904818e2
"s390/kernel: introduce fpu-internal.h with fpu helper functions"
introduced the fpregs_store / fp_regs_load helper. These function
fail to save and restore the floating pointer control registers.

The effect is that the FPC is not correctly handled on signal
delivery and signal return.

Cc: stable@vger.kernel.org # 4.4
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

git commit 80703617
"s390: add support for vector extension"
broke 31-bit compat processes in regard to signal handling.

The restore_sigregs_ext32() function is used to restore the additional
elements from the user space signal frame. Among the additional elements
are the upper registers halves for 64-bit register support for 31-bit
processes. The copy_from_user that is used to retrieve the high-gprs
array from the user stack uses an incorrect length, 8 bytes instead of
64 bytes. This causes incorrect upper register halves to get loaded.

Cc: stable@vger.kernel.org # 3.8+
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Pull x86 fixes from Ingo Molnar:
 "This is unusually large, partly due to the EFI fixes that prevent
  accidental deletion of EFI variables through efivarfs that may brick
  machines.  These fixes are somewhat involved to maintain compatibility
  with existing install methods and other usage modes, while trying to
  turn off the 'rm -rf' bricking vector.

  Other fixes are for large page ioremap()s and for non-temporal
  user-memcpy()s"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Fix vmalloc_fault() to handle large pages properly
  hpet: Drop stale URLs
  x86/uaccess/64: Handle the caching of 4-byte nocache copies properly in __copy_user_nocache()
  x86/uaccess/64: Make the __copy_user_nocache() assembly code more readable
  lib/ucs2_string: Correct ucs2 -> utf8 conversion
  efi: Add pstore variables to the deletion whitelist
  efi: Make efivarfs entries immutable by default
  efi: Make our variable validation list include the guid
  efi: Do variable name validation tests in utf8
  efi: Use ucs2_as_utf8 in efivarfs instead of open coding a bad version
  lib/ucs2_string: Add ucs2 -> utf8 helper functions

Pull perf fixes from Ingo Molnar:
 "A handful of CPU hotplug related fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Plug potential memory leak in CPU_UP_PREPARE
  perf/core: Remove the bogus and dangerous CPU_DOWN_FAILED hotplug state
  perf/core: Remove bogus UP_CANCELED hotplug state
  perf/x86/amd/uncore: Plug reference leak

Pull powerpc fixes from Michael Ellerman:
 - Fix build error on 32-bit with checkpoint restart from Aneesh Kumar
 - Fix dedotify for binutils >= 2.26 from Andreas Schwab
 - Don't trace hcalls on offline CPUs from Denis Kirjanov
 - eeh: Fix stale cached primary bus from Gavin Shan
 - eeh: Fix stale PE primary bus from Gavin Shan
 - mm: Fix Multi hit ERAT cause by recent THP update from Aneesh Kumar K.V
 - ioda: Set "read" permission when "write" is set from Alexey Kardashevskiy

* tag 'powerpc-4.5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/ioda: Set "read" permission when "write" is set
  powerpc/mm: Fix Multi hit ERAT cause by recent THP update
  powerpc/powernv: Fix stale PE primary bus
  powerpc/eeh: Fix stale cached primary bus
  powerpc/pseries: Don't trace hcalls on offline CPUs
  powerpc: Fix dedotify for binutils >= 2.26
  powerpc/book3s_32: Fix build error with checkpoint restart

Pull dmaengine fixes from Vinod Koul:
 "A few fixes for drivers, nothing major here.

  Fixes are: iotdma fix to restart channels, new ID for wildcat PCH,
  residue fix for edma, disable irq for non-cyclic in dw"

* tag 'dmaengine-fix-4.5-rc5' of git://git.infradead.org/users/vkoul/slave-dma:
  dmaengine: dw: disable BLOCK IRQs for non-cyclic xfer
  dmaengine: edma: fix residue race for cyclic
  dmaengine: dw: pci: add ID for WildcatPoint PCH
  dmaengine: IOATDMA: fix timer code that continues to restart channels during idle

Pull clk driver fixes from Stephen Boyd:
 "An assortment of vendor specific clk drivers fixes, most notably
  fallout from adding Tegra210 and rockchip rk3036/rk3368 drivers this
  cycle.

  There's also the random smattering of sparse/checker fixes, a build
  "fix" to get the Tango clk driver to compile because the Kconfig
  symbol was renamed after the fact, and a clk gpio fix for a patch
  mismerge"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (28 commits)
  clk: gpio: Really allow an optional clock= DT property
  Revert "clk: qcom: Specify LE device endianness"
  clk: versatile: mask VCO bits before writing
  clk: tegra: super: Fix sparse warnings for functions not declared as static
  clk: tegra: Fix sparse warnings for functions not declared as static
  clk: tegra: Fix sparse warning for pll_m
  clk: tegra: Use definition for pll_u override bit
  clk: tegra: Fix warning caused by pll_u failing to lock
  clk: tegra: Fix clock sources for Tegra210 EMC
  clk: tegra: Add the APB2APE audio clock on Tegra210
  clk: tegra: Add missing of_node_put()
  clk: tegra: Fix PLLE SS coefficients
  clk: tegra: Fix typos around clearing PLLE bits during enable
  clk: tegra: Do not disable PLLE when under hardware control
  clk: tegra: Fix pllx dyn step calculation
  clk: tegra: pll: Fix potential sleeping-while-atomic
  clk: tegra: Fix the misnaming of nvenc from msenc
  clk: tegra: Fix naming of MISC registers
  clk: tango4: rename ARCH_TANGOX to ARCH_TANGO
  clk: scpi: Fix checking return value of platform_device_register_simple()
  ...

Pull more drm fixes from Dave Airlie:
 "Some more fixes trickled in:

  A bunch of VC4 ones since it's a pretty new driver not much chance of
  regressions, and it fixes GPU resets.

  Also one atomic fix, one set of fixes for a common bug in TTM cleanup,
  and one i915 hotplug fix"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/nouveau: use post-decrement in error handling
  drm/atomic: Allow for holes in connector state, v2.
  drm/i915: Fix hpd live status bits for g4x
  drm/vc4: Use runtime PM to power cycle the device when the GPU hangs.
  drm/vc4: Enable runtime PM.
  drm/vc4: Fix spurious GPU resets due to BO reuse.
  drm/vc4: Drop error message on seqno wait timeouts.
  drm/vc4: Fix -ERESTARTSYS error return from BO waits.
  drm/vc4: Return an ERR_PTR from BO creation instead of NULL.
  drm/vc4: Fix the clear color for the first tile rendered.
  drm/vc4: Validate that WAIT_BO padding is cleared.
  drm/radeon: use post-decrement in error handling
  drm/amdgpu: use post-decrement in error handling

In __request_region, if a conflict with a BUSY and MUXED resource is
detected, then the caller goes to sleep and waits for the resource to be
released.  A pointer on the conflicting resource is kept.  At wake-up
this pointer is used as a parent to retry to request the region.

A first problem is that this pointer might well be invalid (if for
example the conflicting resource have already been freed).  Another
problem is that the next call to __request_region() fails to detect a
remaining conflict.  The previously conflicting resource is passed as a
parameter and __request_region() will look for a conflict among the
children of this resource and not at the resource itself.  It is likely
to succeed anyway, even if there is still a conflict.

Instead, the parent of the conflicting resource should be passed to
__request_region().

As a fix, this patch doesn't update the parent resource pointer in the
case we have to wait for a muxed region right after.
Reported-and-tested-by: Vincent Pelletier <plr.vincent@gmail.com>
Signed-off-by: Simon Guinot <simon.guinot@sequanux.org>
Tested-by: Vincent Donnefort <vdonnefort@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull ext4 bugfixes from Ted Ts'o:
 "Miscellaneous ext4 bug fixes for v4.5"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: fix crashes in dioread_nolock mode
  ext4: fix bh->b_state corruption
  ext4: fix memleak in ext4_readdir()
  ext4: remove unused parameter "newblock" in convert_initialized_extent()
  ext4: don't read blocks from disk after extents being swapped
  ext4: fix potential integer overflow
  ext4: add a line break for proc mb_groups display
  ext4: ioctl: fix erroneous return value
  ext4: fix scheduling in atomic on group checksum failure
  ext4 crypto: move context consistency check to ext4_file_open()
  ext4 crypto: revalidate dentry after adding or removing the key

Pull btrfs fix from Chris Mason:
 "My for-linus-4.5 branch has a btrfs DIO error passing fix.

  I know how much you love DIO, so I'm going to suggest against reading
  it.  We'll follow up with a patch to drop the error arg from
  dio_end_io in the next merge window."

* 'for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: fix direct IO requests not reporting IO error to user space

Merge fixes from Andrew Morton:
 "10 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm: slab: free kmem_cache_node after destroy sysfs file
  ipc/shm: handle removed segments gracefully in shm_mmap()
  MAINTAINERS: update Kselftest Framework mailing list
  devm_memremap_release(): fix memremap'd addr handling
  mm/hugetlb.c: fix incorrect proc nr_hugepages value
  mm, x86: fix pte_page() crash in gup_pte_range()
  fsnotify: turn fsnotify reaper thread into a workqueue job
  Revert "fsnotify: destroy marks with call_srcu instead of dedicated thread"
  mm: fix regression in remap_file_pages() emulation
  thp, dax: do not try to withdraw pgtable from non-anon VMA

Pull arm64 fixes from Will Deacon:
 "Here are some more arm64 fixes for 4.5.  This has mostly come from
  Yang Shi, who saw some issues under -rt that also affect mainline.
  The rest of it is pretty small, but still worth having.

  We've got an old issue outstanding with valid_user_regs which will
  likely wait until 4.6 (since it would really benefit from some time in
  -next) and another issue with kasan and idle which should be fixed
  next week.

  Apart from that, pretty quiet here (and still no sign of the THP issue
  reported on s390...)

  Summary:

   - Allow EFI stub to use strnlen(), which is required by recent libfdt

   - Avoid smp_processor_id() in preempt context during unwinding

   - Avoid false Kasan warnings during unwinding

   - Ensure early devices are picked up by the IOMMU DMA ops

   - Avoid rebuilding the kernel for the 'install' target

   - Run fixup handlers for alignment faults on userspace access"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: mm: allow the kernel to handle alignment faults on user accesses
  arm64: kbuild: make "make install" not depend on vmlinux
  arm64: dma-mapping: fix handling of devices registered before arch_initcall
  arm64/efi: Make strnlen() available to the EFI namespace
  arm/arm64: crypto: assure that ECB modes don't require an IV
  arm64: make irq_stack_ptr more robust
  arm64: debug: re-enable irqs before sending breakpoint SIGTRAP
  arm64: disable kasan when accessing frame->fp in unwind_frame

Pull s390 fixes from Martin Schwidefsky:
 "Several bug fixes:

   - There are four different stack tracers, and three of them have
     bugs.  For 4.5 the bugs are fixed and we prepare a cleanup patch
     for the next merge window.

   - Three bug fixes for the dasd driver in regard to parallel access
     volumes and the new max_dev_sectors block device queue limit

   - The irq restore optimization needs a fixup for memcpy_real

   - The diagnose trace code has a conflict with lockdep"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/dasd: fix performance drop
  s390/maccess: reduce stnsm instructions
  s390/diag: avoid lockdep recursion
  s390/dasd: fix refcount for PAV reassignment
  s390/dasd: prevent incorrect length error under z/VM after PAV changes
  s390: fix DAT off memory access, e.g. on kdump
  s390/oprofile: fix address range for asynchronous stack
  s390/perf_event: fix address range for asynchronous stack
  s390/stacktrace: add save_stack_trace_regs()
  s390/stacktrace: save full stack traces
  s390/stacktrace: add missing end marker
  s390/stacktrace: fix address ranges for asynchronous and panic stack
  s390/stacktrace: fix save_stack_trace_tsk() for current task

Pull Pin control fixes from Linus Walleij:
 "Pin control fixes for the v4.5 series, all are individual driver
  fixes:

   - Fix the PXA2xx driver to export its init function so we do not
     break modular compiles.
   - Hide unused functions in the Nomadik driver.
   - Fix up direction control in the Mediatek driver.
   - Toggle the sunxi GPIO lines to input when you read them on the H3
     GPIO controller, lest you only get garbage.
   - Fix up the number of settings in the MVEBU driver.
   - Fix a serious SMP race condition in the Samsung driver"

* tag 'pinctrl-v4.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  pinctrl: samsung: fix SMP race condition
  pinctrl: mvebu: fix num_settings in mpp group assignment
  pinctrl: sunxi: H3 requires irq_read_needs_mux
  pinctrl: mediatek: fix direction control issue
  pinctrl: nomadik: hide unused functions
  pinctrl: pxa: export pxa2xx_pinctrl_init()

Pull sound fixes from Takashi Iwai:
 "This update contains again a few more fixes for ALSA core stuff
  although it's no longer high flux: two race fixes in sequencer and one
  PCM race fix for non-atomic PCM ops.

  In addition, HD-audio gained a similar fix for race at reloading the
  driver"

* tag 'sound-4.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: pcm: Fix rwsem deadlock for non-atomic PCM stream
  ALSA: seq: Fix double port list deletion
  ALSA: hda - Cancel probe work instead of flush at remove
  ALSA: seq: Fix leak of pool buffer at concurrent writes

Although we don't expect to take alignment faults on access to normal
memory, misbehaving (i.e. buggy) user code can pass MMIO pointers into
system calls, leading to things like get_user accessing device memory.

Rather than OOPS the kernel, allow any exception fixups to run and
return something like -EFAULT back to userspace. This makes the
behaviour more consistent with userspace, even though applications with
access to device mappings can easily cause other issues if they try
hard enough.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Eun Taik Lee <eun.taik.lee@samsung.com>
[will: dropped __kprobes annotation and rewrote commit mesage]
Signed-off-by: Will Deacon <will.deacon@arm.com>

For the same reason as commit 19514fc6 ("arm, kbuild: make "make
install" not depend on vmlinux"), the install targets should never
trigger the rebuild of the kernel.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

Competing overwrite DIO in dioread_nolock mode will just overwrite
pointer to io_end in the inode. This may result in data corruption or
extent conversion happening from IO completion interrupt because we
don't properly set buffer_defer_completion() when unlocked DIO races
with locked DIO to unwritten extent.

Since unlocked DIO doesn't need io_end for anything, just avoid
allocating it and corrupting pointer from inode for locked DIO.
A cleaner fix would be to avoid these games with io_end pointer from the
inode but that requires more intrusive changes so we leave that for
later.

Cc: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

ext4 can update bh->b_state non-atomically in _ext4_get_block() and
ext4_da_get_block_prep(). Usually this is fine since bh is just a
temporary storage for mapping information on stack but in some cases it
can be fully living bh attached to a page. In such case non-atomic
update of bh->b_state can race with an atomic update which then gets
lost. Usually when we are mapping bh and thus updating bh->b_state
non-atomically, nobody else touches the bh and so things work out fine
but there is one case to especially worry about: ext4_finish_bio() uses
BH_Uptodate_Lock on the first bh in the page to synchronize handling of
PageWriteback state. So when blocksize < pagesize, we can be atomically
modifying bh->b_state of a buffer that actually isn't under IO and thus
can race e.g. with delalloc trying to map that buffer. The result is
that we can mistakenly set / clear BH_Uptodate_Lock bit resulting in the
corruption of PageWriteback state or missed unlock of BH_Uptodate_Lock.

Fix the problem by always updating bh->b_state bits atomically.

CC: stable@vger.kernel.org
Reported-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

We need to use post-decrement to get the dma_map_page undone also for
i==0, and to avoid some very unpleasant behaviour if dma_map_page
failed already at i==0.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

Because we record connector_mask using 1 << drm_connector_index now
the connector_mask should stay the same even when other connectors
are removed. This was not the case with MST, in that case when removing
a connector all other connectors may change their index.

This is fixed by waiting until the first get_connector_state to allocate
connector_state, and force reallocation when state is too small.

As a side effect connector arrays no longer have to be preallocated,
and can be allocated on first use which means a less allocations in
the page flip only path.

Changes since v1:
- Whitespace. (Ville)
- Call ida_remove when destroying the connector. (Ville)
- u32 alloc -> int. (Ville)

Fixes: 14de6c44 ("drm/atomic: Remove drm_atomic_connectors_for_crtc.")
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Lyude <cpaul@redhat.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

We mis-merged the original patch from Russell here and so the
patch went almost all the way, except that we still failed to
probe when there wasn't a clocks property in the DT node. Allow
that case by making a negative value from
of_clk_get_parent_count() into "no parents", like the original
patch did.

Fixes: 7ed88aa2 ("clk: fix clk-gpio.c with optional clock= DT property")
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Michael Turquette <mturquette@baylibre.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

This pull request fixes GPU reset (which was disabled shortly after
V3D integration due to build breakage) and waits for idle in the
presence of signals (which X likes to do a lot).

* tag 'drm-vc4-fixes-2016-02-17' of github.com:anholt/linux:
  drm/vc4: Use runtime PM to power cycle the device when the GPU hangs.
  drm/vc4: Enable runtime PM.
  drm/vc4: Fix spurious GPU resets due to BO reuse.
  drm/vc4: Drop error message on seqno wait timeouts.
  drm/vc4: Fix -ERESTARTSYS error return from BO waits.
  drm/vc4: Return an ERR_PTR from BO creation instead of NULL.
  drm/vc4: Fix the clear color for the first tile rendered.
  drm/vc4: Validate that WAIT_BO padding is cleared.

Just two small fixes in the ttm_tt_populate error handling; one for radeon,
one for amdgpu.

* 'drm-fixes-4.5' of git://people.freedesktop.org/~agd5f/linux:
  drm/radeon: use post-decrement in error handling
  drm/amdgpu: use post-decrement in error handling

single g4x hpd fix.

* tag 'drm-intel-fixes-2016-02-18' of git://anongit.freedesktop.org/drm-intel:
  drm/i915: Fix hpd live status bits for g4x

Pull livepatching fixes from Jiri Kosina:

 - regression (from 4.4) fix for ordering issue, introduced by an
   earlier ftrace change, that broke live patching of modules.

   The fix replaces the ftrace module notifier by direct call in order
   to make the ordering guaranteed and well-defined.  The patch, from
   Jessica Yu, has been acked both by Steven and Rusty

 - error message fix from Miroslav Benes

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
  ftrace/module: remove ftrace module notifier
  livepatch: change the error message in asm/livepatch.h header files

Pull SCSI fixes from James Bottomley:
 "Two simple fixes.

  One prevents a soft lockup on some target removal scenarios and the
  other prevents us trying to probe the marvell console device, which
  causes it to time out and need the bus resetting"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: fix soft lockup in scsi_remove_target() on module removal
  SCSI: Add Marvell configuration device to VPD blacklist

When slub_debug alloc_calls_show is enabled we will try to track
location and user of slab object on each online node, kmem_cache_node
structure and cpu_cache/cpu_slub shouldn't be freed till there is the
last reference to sysfs file.

This fixes the following panic:

   BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
   IP:  list_locations+0x169/0x4e0
   PGD 257304067 PUD 438456067 PMD 0
   Oops: 0000 [#1] SMP
   CPU: 3 PID: 973074 Comm: cat ve: 0 Not tainted 3.10.0-229.7.2.ovz.9.30-00007-japdoll-dirty #2 9.30
   Hardware name: DEPO Computers To Be Filled By O.E.M./H67DE3, BIOS L1.60c 07/14/2011
   task: ffff88042a5dc5b0 ti: ffff88037f8d8000 task.ti: ffff88037f8d8000
   RIP: list_locations+0x169/0x4e0
   Call Trace:
     alloc_calls_show+0x1d/0x30
     slab_attr_show+0x1b/0x30
     sysfs_read_file+0x9a/0x1a0
     vfs_read+0x9c/0x170
     SyS_read+0x58/0xb0
     system_call_fastpath+0x16/0x1b
   Code: 5e 07 12 00 b9 00 04 00 00 3d 00 04 00 00 0f 4f c1 3d 00 04 00 00 89 45 b0 0f 84 c3 00 00 00 48 63 45 b0 49 8b 9c c4 f8 00 00 00 <48> 8b 43 20 48 85 c0 74 b6 48 89 df e8 46 37 44 00 48 8b 53 10
   CR2: 0000000000000020

Separated __kmem_cache_release from __kmem_cache_shutdown which now
called on slab_kmem_cache_release (after the last reference to sysfs
file object has dropped).

Reintroduced locking in free_partial as sysfs file might access cache's
partial list after shutdowning - partial revert of the commit
69cb8e6b ("slub: free slabs without holding locks").  Zap
__remove_partial and use remove_partial (w/o underscores) as
free_partial now takes list_lock which s partial revert for commit
1e4dd946 ("slub: do not assert not having lock in removing freed
partial")
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Suggested-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

remap_file_pages(2) emulation can reach file which represents removed
IPC ID as long as a memory segment is mapped.  It breaks expectations of
IPC subsystem.

Test case (rewritten to be more human readable, originally autogenerated
by syzkaller[1]):

	#define _GNU_SOURCE
	#include <stdlib.h>
	#include <sys/ipc.h>
	#include <sys/mman.h>
	#include <sys/shm.h>

	#define PAGE_SIZE 4096

	int main()
	{
		int id;
		void *p;

		id = shmget(IPC_PRIVATE, 3 * PAGE_SIZE, 0);
		p = shmat(id, NULL, 0);
		shmctl(id, IPC_RMID, NULL);
		remap_file_pages(p, 3 * PAGE_SIZE, 0, 7, 0);

	        return 0;
	}

The patch changes shm_mmap() and code around shm_lock() to propagate
locking error back to caller of shm_mmap().

[1] http://github.com/google/syzkallerSigned-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Kselftest Framework now has a dedicated mailing list linux-kselftest.
Update the entry in MAINTAINERS file.
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The pmem driver calls devm_memremap() to map a persistent memory range.
When the pmem driver is unloaded, this memremap'd range is not released
so the kernel will leak a vma.

Fix devm_memremap_release() to handle a given memremap'd address
properly.
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Matthew Wilcox <willy@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>

Currently incorrect default hugepage pool size is reported by proc
nr_hugepages when number of pages for the default huge page size is
specified twice.

When multiple huge page sizes are supported, /proc/sys/vm/nr_hugepages
indicates the current number of pre-allocated huge pages of the default
size.  Basically /proc/sys/vm/nr_hugepages displays default_hstate->
max_huge_pages and after boot time pre-allocation, max_huge_pages should
equal the number of pre-allocated pages (nr_hugepages).

Test case:

Note that this is specific to x86 architecture.

Boot the kernel with command line option 'default_hugepagesz=1G
hugepages=X hugepagesz=2M hugepages=Y hugepagesz=1G hugepages=Z'.  After
boot, 'cat /proc/sys/vm/nr_hugepages' and 'sysctl -a | grep hugepages'
returns the value X.  However, dmesg output shows that Z huge pages were
pre-allocated.

So, the root cause of the problem here is that the global variable
default_hstate_max_huge_pages is set if a default huge page size is
specified (directly or indirectly) on the command line.  After the command
line processing in hugetlb_init, if default_hstate_max_huge_pages is set,
the value is assigned to default_hstae.max_huge_pages.  However,
default_hstate.max_huge_pages may have already been set based on the
number of pre-allocated huge pages of default_hstate size.

The solution to this problem is if hstate->max_huge_pages is already set
then it should not set as a result of global max_huge_pages value.
Basically if the value of the variable hugepages is set multiple times on
a command line for a specific supported hugepagesize then proc layer
should consider the last specified value.
Signed-off-by: Vaishali Thakkar <vaishali.thakkar@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 3565fce3 ("mm, x86: get_user_pages() for dax mappings") has
moved up the pte_page(pte) in x86's fast gup_pte_range(), for no
discernible reason: put it back where it belongs, after the pte_flags
check and the pfn_valid cross-check.

That may be the cause of the NULL pointer dereference in
gup_pte_range(), seen when vfio called vaddr_get_pfn() when starting a
qemu-kvm based VM.
Signed-off-by: Hugh Dickins <hughd@google.com>
Reported-by: Michael Long <Harn-Solo@gmx.de>
Tested-by: Michael Long <Harn-Solo@gmx.de>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We don't require a dedicated thread for fsnotify cleanup.  Switch it
over to a workqueue job instead that runs on the system_unbound_wq.

In the interest of not thrashing the queued job too often when there are
a lot of marks being removed, we delay the reaper job slightly when
queueing it, to allow several to gather on the list.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Tested-by: Eryu Guan <guaneryu@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Eric Paris <eparis@parisplace.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This reverts commit c510eff6 ("fsnotify: destroy marks with
call_srcu instead of dedicated thread").

Eryu reported that he was seeing some OOM kills kick in when running a
testcase that adds and removes inotify marks on a file in a tight loop.

The above commit changed the code to use call_srcu to clean up the
marks.  While that does (in principle) work, the srcu callback job is
limited to cleaning up entries in small batches and only once per jiffy.
It's easily possible to overwhelm that machinery with too many call_srcu
callbacks, and Eryu's reproduer did just that.

There's also another potential problem with using call_srcu here.  While
you can obviously sleep while holding the srcu_read_lock, the callbacks
run under local_bh_disable, so you can't sleep there.

It's possible when putting the last reference to the fsnotify_mark that
we'll end up putting a chain of references including the fsnotify_group,
uid, and associated keys.  While I don't see any obvious ways that that
could occurs, it's probably still best to avoid using call_srcu here
after all.

This patch reverts the above patch.  A later patch will take a different
approach to eliminated the dedicated thread here.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Reported-by: Eryu Guan <guaneryu@gmail.com>
Tested-by: Eryu Guan <guaneryu@gmail.com>
Cc: Jan Kara <jack@suse.com>
Cc: Eric Paris <eparis@parisplace.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Grazvydas Ignotas has reported a regression in remap_file_pages()
emulation.

Testcase:
	#define _GNU_SOURCE
	#include <assert.h>
	#include <stdlib.h>
	#include <stdio.h>
	#include <sys/mman.h>

	#define SIZE    (4096 * 3)

	int main(int argc, char **argv)
	{
		unsigned long *p;
		long i;

		p = mmap(NULL, SIZE, PROT_READ | PROT_WRITE,
				MAP_SHARED | MAP_ANONYMOUS, -1, 0);
		if (p == MAP_FAILED) {
			perror("mmap");
			return -1;
		}

		for (i = 0; i < SIZE / 4096; i++)
			p[i * 4096 / sizeof(*p)] = i;

		if (remap_file_pages(p, 4096, 0, 1, 0)) {
			perror("remap_file_pages");
			return -1;
		}

		if (remap_file_pages(p, 4096 * 2, 0, 1, 0)) {
			perror("remap_file_pages");
			return -1;
		}

		assert(p[0] == 1);

		munmap(p, SIZE);

		return 0;
	}

The second remap_file_pages() fails with -EINVAL.

The reason is that remap_file_pages() emulation assumes that the target
vma covers whole area we want to over map.  That assumption is broken by
first remap_file_pages() call: it split the area into two vma.

The solution is to check next adjacent vmas, if they map the same file
with the same flags.

Fixes: c8d78c18 ("mm: replace remap_file_pages() syscall with emulation")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Grazvydas Ignotas <notasas@gmail.com>
Tested-by: Grazvydas Ignotas <notasas@gmail.com>
Cc: <stable@vger.kernel.org>	[4.0+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

DAX doesn't deposit pgtables when it maps huge pages: nothing to
withdraw. It can lead to crash.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

A non-atomic PCM stream may take snd_pcm_link_rwsem rw semaphore twice
in the same code path, e.g. one in snd_pcm_action_nonatomic() and
another in snd_pcm_stream_lock().  Usually this is OK, but when a
write lock is issued between these two read locks, the problem
happens: the write lock is blocked due to the first reade lock, and
the second read lock is also blocked by the write lock.  This
eventually deadlocks.

The reason is the way rwsem manages waiters; it's queued like FIFO, so
even if the writer itself doesn't take the lock yet, it blocks all the
waiters (including reads) queued after it.

As a workaround, in this patch, we replace the standard down_write()
with an spinning loop.  This is far from optimal, but it's good
enough, as the spinning time is supposed to be relatively short for
normal PCM operations, and the code paths requiring the write lock
aren't called so often.
Reported-by: Vinod Koul <vinod.koul@intel.com>
Tested-by: Ramesh Babu <ramesh.babu@intel.com>
Cc: <stable@vger.kernel.org> # v3.18+
Signed-off-by: Takashi Iwai <tiwai@suse.de>