Commit Graph

871854 Commits

Author SHA1 Message Date
Stephen Rothwell
18217da361 powerpc/64s/radix: Fix build failure with RADIX_MMU=n
After merging the powerpc tree, today's linux-next build (powerpc64
allnoconfig) failed like this:

 arch/powerpc/mm/book3s64/pgtable.c:216:3:
 error: implicit declaration of function 'radix__flush_all_lpid_guest'

radix__flush_all_lpid_guest() is only declared for
CONFIG_PPC_RADIX_MMU which is not set for this build.

Fix it by adding an empty version for the RADIX_MMU=n case, which
should never be called.

Fixes: 99161de3a2 ("powerpc/64s/radix: tidy up TLB flushing code")
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
[mpe: Munge change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190930101342.36c1afa0@canb.auug.org.au
2019-10-09 17:16:58 +11:00
Pavel Shilovsky
0b3d0ef984 CIFS: Force reval dentry if LOOKUP_REVAL flag is set
Mark inode for force revalidation if LOOKUP_REVAL flag is set.
This tells the client to actually send a QueryInfo request to
the server to obtain the latest metadata in case a directory
or a file were changed remotely. Only do that if the client
doesn't have a lease for the file to avoid unneeded round
trips to the server.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-10-09 00:10:50 -05:00
Pavel Shilovsky
c82e5ac7fe CIFS: Force revalidate inode when dentry is stale
Currently the client indicates that a dentry is stale when inode
numbers or type types between a local inode and a remote file
don't match. If this is the case attributes is not being copied
from remote to local, so, it is already known that the local copy
has stale metadata. That's why the inode needs to be marked for
revalidation in order to tell the VFS to lookup the dentry again
before openning a file. This prevents unexpected stale errors
to be returned to the user space when openning a file.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-10-09 00:10:50 -05:00
Steve French
d4cfbf04b2 smb3: Fix regression in time handling
Fixes: cb7a69e605 ("cifs: Initialize filesystem timestamp ranges")

Only very old servers (e.g. OS/2 and DOS) did not support
DCE TIME (100 nanosecond granularity).  Fix the checks used
to set minimum and maximum times.

Fixes xfstest generic/258 (on 5.4-rc1 and later)

CC: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-10-09 00:10:38 -05:00
Steve French
d0959b080b smb3: remove noisy debug message and minor cleanup
Message was intended only for developer temporary build
In addition cleanup two minor warnings noticed by Coverity
and a trivial change to workaround a sparse warning

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-10-08 18:19:40 -07:00
Linus Torvalds
e3280b54af LED fixes for 5.4-rc3.
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Merge tag 'led-fixes-for-5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds

Pull LED fixes from Jacek Anaszewski:

 - fix a leftover from earlier stage of development in the documentation
   of recently added led_compose_name() and fix old mistake in the
   documentation of led_set_brightness_sync() parameter name.

  - MAINTAINERS: add pointer to Pavel Machek's linux-leds.git tree.
    Pavel is going to take over LED tree maintainership from myself.

* tag 'led-fixes-for-5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds:
  Add my linux-leds branch to MAINTAINERS
  leds: core: Fix leds.h structure documentation
2019-10-08 15:36:04 -07:00
Pavel Machek
4050d21d20 Add my linux-leds branch to MAINTAINERS
Add pointer to my git tree to MAINTAINERS. I'd like to maintain
linux-leds for-next branch for 5.5.

Signed-off-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2019-10-08 22:09:08 +02:00
Dan Murphy
e3f1271474 leds: core: Fix leds.h structure documentation
Update the leds.h structure documentation to define the
correct arguments.

Signed-off-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2019-10-08 22:05:58 +02:00
Linus Torvalds
d5001955c2 GPIO fixes for the v5.4 series:
- Don't clear FLAG_IS_OUT when emulating open drain/source in
   gpiolib.
 - Fix up the usage of nonexclusive GPIO descriptors from device
   trees.
 - Fix the incorrect IEC offset when toggling trigger edge in
   the Spreadtrum driver.
 - Use the correct unit for debounce settings in the MAX77620
   driver.
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Merge tag 'gpio-v5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO fixes from Linus Walleij:

 - don't clear FLAG_IS_OUT when emulating open drain/source in gpiolib

 - fix up the usage of nonexclusive GPIO descriptors from device trees

 - fix the incorrect IEC offset when toggling trigger edge in the
   Spreadtrum driver

 - use the correct unit for debounce settings in the MAX77620 driver

* tag 'gpio-v5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio: max77620: Use correct unit for debounce times
  gpio: eic: sprd: Fix the incorrect EIC offset when toggling
  gpio: fix getting nonexclusive gpiods from DT
  gpiolib: don't clear FLAG_IS_OUT when emulating open-drain/open-source
2019-10-08 10:55:22 -07:00
Linus Torvalds
2ef459167a selinux/stable-5.4 PR 20191007
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Merge tag 'selinux-pr-20191007' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux

Pull selinuxfix from Paul Moore:
 "One patch to ensure we don't copy bad memory up into userspace"

* tag 'selinux-pr-20191007' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: fix context string corruption in convert_context()
2019-10-08 10:51:37 -07:00
Linus Torvalds
f54e66ae77 linux-kselftest-5.4-rc3
This Kselftest update for Linux 5.4-rc3 consists fixes for existing
 tests and the framework. Cristian Marussi's patches add ability to
 skip targets (tests) and exclude tests that didn't build from run-list.
 These patches improve the Kselftest results. Ability to skip targets
 helps avoid running tests that aren't supported in certain environments.
 As an example, bpf tests from mainline aren't supported on stable kernels
 and have dependency on bleeding edge llvm. Being able to skip bpf on
 systems that can't meet this llvm dependency will be helpful.
 
 Kselftest can be built and installed from the main Makefile. This change
 help simplify Kselftest use-cases which addresses request from users.
 
 Kees Cook added per test timeout support to limit individual test run-time.
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Merge tag 'linux-kselftest-5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull Kselftest fixes from Shuah Khan:
 "Fixes for existing tests and the framework.

  Cristian Marussi's patches add the ability to skip targets (tests) and
  exclude tests that didn't build from run-list. These patches improve
  the Kselftest results. Ability to skip targets helps avoid running
  tests that aren't supported in certain environments. As an example,
  bpf tests from mainline aren't supported on stable kernels and have
  dependency on bleeding edge llvm. Being able to skip bpf on systems
  that can't meet this llvm dependency will be helpful.

  Kselftest can be built and installed from the main Makefile. This
  change help simplify Kselftest use-cases which addresses request from
  users.

  Kees Cook added per test timeout support to limit individual test
  run-time"

* tag 'linux-kselftest-5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  selftests: watchdog: Add command line option to show watchdog_info
  selftests: watchdog: Validate optional file argument
  selftests/kselftest/runner.sh: Add 45 second timeout per test
  kselftest: exclude failed TARGETS from runlist
  kselftest: add capability to skip chosen TARGETS
  selftests: Add kselftest-all and kselftest-install targets
2019-10-08 10:49:05 -07:00
Kan Liang
8d7c6ac3b2 x86/cpu: Add Comet Lake to the Intel CPU models header
Comet Lake is the new 10th Gen Intel processor. Add two new CPU model
numbers to the Intel family list.

The CPU model numbers are not published in the SDM yet but they come
from an authoritative internal source.

 [ bp: Touch up commit message. ]

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Cc: ak@linux.intel.com
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/1570549810-25049-2-git-send-email-kan.liang@linux.intel.com
2019-10-08 19:01:31 +02:00
Masahiro Yamada
fcfacb9f83 doc: move namespaces.rst from kbuild/ to core-api/
We discussed a better location for this file, and agreed that
core-api/ is a good fit. Rename it to symbol-namespaces.rst
for disambiguation, and also add it to index.rst and MAINTAINERS.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Matthias Maennich <maennich@google.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2019-10-08 17:40:01 +02:00
Yunfeng Ye
3e7c93bd04 arm64: armv8_deprecated: Checking return value for memory allocation
There are no return value checking when using kzalloc() and kcalloc() for
memory allocation. so add it.

Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Signed-off-by: Will Deacon <will@kernel.org>
2019-10-08 13:34:04 +01:00
Arvind Sankar
bec5007770 lib/string: Make memzero_explicit() inline instead of external
With the use of the barrier implied by barrier_data(), there is no need
for memzero_explicit() to be extern. Making it inline saves the overhead
of a function call, and allows the code to be reused in arch/*/purgatory
without having to duplicate the implementation.

Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H . Peter Anvin <hpa@zytor.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephan Mueller <smueller@chronox.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-crypto@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Fixes: 906a4bb97f ("crypto: sha256 - Use get/put_unaligned_be32 to get input, memzero_explicit")
Link: https://lkml.kernel.org/r/20191007220000.GA408752@rani.riverdale.lan
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-08 13:27:05 +02:00
Sami Tolvanen
fbcfb8f027 x86/cpu/vmware: Use the full form of INL in VMWARE_PORT
LLVM's assembler doesn't accept the short form INL instruction:

  inl (%%dx)

but instead insists on the output register to be explicitly specified:

  <inline asm>:1:7: error: invalid operand for instruction
          inl (%dx)
             ^
  LLVM ERROR: Error parsing inline asm

Use the full form of the instruction to fix the build.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Thomas Hellstrom <thellstrom@vmware.com>
Cc: clang-built-linux@googlegroups.com
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: virtualization@lists.linux-foundation.org
Cc: "VMware, Inc." <pv-drivers@vmware.com>
Cc: x86-ml <x86@kernel.org>
Link: https://github.com/ClangBuiltLinux/linux/issues/734
Link: https://lkml.kernel.org/r/20191007192129.104336-1-samitolvanen@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-08 13:26:42 +02:00
Janakarajan Natarajan
454de1e7d9 x86/asm: Fix MWAITX C-state hint value
As per "AMD64 Architecture Programmer's Manual Volume 3: General-Purpose
and System Instructions", MWAITX EAX[7:4]+1 specifies the optional hint
of the optimized C-state. For C0 state, EAX[7:4] should be set to 0xf.

Currently, a value of 0xf is set for EAX[3:0] instead of EAX[7:4]. Fix
this by changing MWAITX_DISABLE_CSTATES from 0xf to 0xf0.

This hasn't had any implications so far because setting reserved bits in
EAX is simply ignored by the CPU.

 [ bp: Fixup comment in delay_mwaitx() and massage. ]

Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "x86@kernel.org" <x86@kernel.org>
Cc: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20191007190011.4859-1-Janakarajan.Natarajan@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-08 13:25:24 +02:00
Austin Kim
431d39887d btrfs: silence maybe-uninitialized warning in clone_range
GCC throws warning message as below:

‘clone_src_i_size’ may be used uninitialized in this function
[-Wmaybe-uninitialized]
 #define IS_ALIGNED(x, a)  (((x) & ((typeof(x))(a) - 1)) == 0)
                       ^
fs/btrfs/send.c:5088:6: note: ‘clone_src_i_size’ was declared here
 u64 clone_src_i_size;
   ^
The clone_src_i_size is only used as call-by-reference
in a call to get_inode_info().

Silence the warning by initializing clone_src_i_size to 0.

Note that the warning is a false positive and reported by older versions
of GCC (eg. 7.x) but not eg 9.x. As there have been numerous people, the
patch is applied. Setting clone_src_i_size to 0 does not otherwise make
sense and would not do any action in case the code changes in the future.

Signed-off-by: Austin Kim <austindh.kim@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add note ]
Signed-off-by: David Sterba <dsterba@suse.com>
2019-10-08 13:14:55 +02:00
Colin Ian King
be59d57f98 efi/tpm: Fix sanity check of unsigned tbl_size being less than zero
Currently the check for tbl_size being less than zero is always false
because tbl_size is unsigned. Fix this by making it a signed int.

Addresses-Coverity: ("Unsigned compared against 0")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jerry Snitselaar <jsnitsel@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-janitors@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Fixes: e658c82be5 ("efi/tpm: Only set 'efi_tpm_final_log_size' after successful event log parsing")
Link: https://lkml.kernel.org/r/20191008100153.8499-1-colin.king@canonical.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-08 13:01:09 +02:00
Laurent Pinchart
cc635be34e drm/panel: tpo-td043mtea1: Fix SPI alias
The panel-tpo-td043mtea1 driver incorrectly includes the OF vendor
prefix in its SPI alias. Fix it, and move the manual alias to an SPI
module device table.

Fixes: dc2e1e5b27 ("drm/panel: Add driver for the Toppoly TD043MTEA1 panel")
Reported-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191007170801.27647-6-laurent.pinchart@ideasonboard.com
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Tested-by: H. Nikolaus Schaller <hns@goldelico.com>
2019-10-08 08:02:20 +03:00
Laurent Pinchart
692a5424b5 drm/panel: tpo-td028ttec1: Fix SPI alias
The panel-tpo-td028ttec1 driver incorrectly includes the OF vendor
prefix in its SPI alias. Fix it.

Fixes: 415b8dd087 ("drm/panel: Add driver for the Toppoly TD028TTEC1 panel")
Reported-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191007170801.27647-5-laurent.pinchart@ideasonboard.com
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Tested-by: H. Nikolaus Schaller <hns@goldelico.com>
Tested-by: Andreas Kemnade <andreas@kemnade.info>
2019-10-08 08:01:50 +03:00
Laurent Pinchart
d82a6ac300 drm/panel: sony-acx565akm: Fix SPI alias
The panel-sony-acx565akm driver incorrectly includes the OF vendor
prefix in its SPI alias. Fix it, and move the manual alias to an SPI
module device table.

Fixes: 1c8fc3f0c5 ("drm/panel: Add driver for the Sony ACX565AKM panel")
Reported-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191007170801.27647-4-laurent.pinchart@ideasonboard.com
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
2019-10-08 08:01:45 +03:00
Laurent Pinchart
cf0c4eb15e drm/panel: nec-nl8048hl11: Fix SPI alias
The panel-nec-nl8048hl11 driver incorrectly includes the OF vendor
prefix in its SPI alias. Fix it, and move the manual alias to an SPI
module device table.

Fixes: df439abe65 ("drm/panel: Add driver for the NEC NL8048HL11 panel")
Reported-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191007170801.27647-3-laurent.pinchart@ideasonboard.com
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
2019-10-08 08:01:34 +03:00
Laurent Pinchart
19305134ad drm/panel: lg-lb035q02: Fix SPI alias
The panel-lg-lb035q02 driver incorrectly includes the OF vendor prefix
in its SPI alias. Fix it, and move the manual alias to an SPI module
device table.

Fixes: f5b0c65424 ("drm/panel: Add driver for the LG Philips LB035Q02 panel")
Reported-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191007170801.27647-2-laurent.pinchart@ideasonboard.com
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
2019-10-08 08:00:55 +03:00
Pavel Begunkov
6805b32ec2 io_uring: remove wait loop spurious wakeups
Any changes interesting to tasks waiting in io_cqring_wait() are
commited with io_cqring_ev_posted(). However, io_ring_drop_ctx_refs()
also tries to do that but with no reason, that means spurious wakeups
every io_free_req() and io_uring_enter().

Just use percpu_ref_put() instead.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-07 21:16:24 -06:00
Linus Torvalds
eda57a0e42 Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
 "The usual shower of hotfixes.

  Chris's memcg patches aren't actually fixes - they're mature but a few
  niggling review issues were late to arrive.

  The ocfs2 fixes are quite old - those took some time to get reviewer
  attention.

  Subsystems affected by this patch series: ocfs2, hotfixes, mm/memcg,
  mm/slab-generic"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm, sl[aou]b: guarantee natural alignment for kmalloc(power-of-two)
  mm, sl[ou]b: improve memory accounting
  mm, memcg: make scan aggression always exclude protection
  mm, memcg: make memory.emin the baseline for utilisation determination
  mm, memcg: proportional memory.{low,min} reclaim
  mm/vmpressure.c: fix a signedness bug in vmpressure_register_event()
  mm/page_alloc.c: fix a crash in free_pages_prepare()
  mm/z3fold.c: claim page in the beginning of free
  kernel/sysctl.c: do not override max_threads provided by userspace
  memcg: only record foreign writebacks with dirty pages when memcg is not disabled
  mm: fix -Wmissing-prototypes warnings
  writeback: fix use-after-free in finish_writeback_work()
  mm/memremap: drop unused SECTION_SIZE and SECTION_MASK
  panic: ensure preemption is disabled during panic()
  fs: ocfs2: fix a possible null-pointer dereference in ocfs2_info_scan_inode_alloc()
  fs: ocfs2: fix a possible null-pointer dereference in ocfs2_write_end_nolock()
  fs: ocfs2: fix possible null-pointer dereferences in ocfs2_xa_prepare_entry()
  ocfs2: clear zero in unaligned direct IO
2019-10-07 16:04:19 -07:00
Vlastimil Babka
59bb47985c mm, sl[aou]b: guarantee natural alignment for kmalloc(power-of-two)
In most configurations, kmalloc() happens to return naturally aligned
(i.e.  aligned to the block size itself) blocks for power of two sizes.

That means some kmalloc() users might unknowingly rely on that
alignment, until stuff breaks when the kernel is built with e.g.
CONFIG_SLUB_DEBUG or CONFIG_SLOB, and blocks stop being aligned.  Then
developers have to devise workaround such as own kmem caches with
specified alignment [1], which is not always practical, as recently
evidenced in [2].

The topic has been discussed at LSF/MM 2019 [3].  Adding a
'kmalloc_aligned()' variant would not help with code unknowingly relying
on the implicit alignment.  For slab implementations it would either
require creating more kmalloc caches, or allocate a larger size and only
give back part of it.  That would be wasteful, especially with a generic
alignment parameter (in contrast with a fixed alignment to size).

Ideally we should provide to mm users what they need without difficult
workarounds or own reimplementations, so let's make the kmalloc()
alignment to size explicitly guaranteed for power-of-two sizes under all
configurations.  What this means for the three available allocators?

* SLAB object layout happens to be mostly unchanged by the patch.  The
  implicitly provided alignment could be compromised with
  CONFIG_DEBUG_SLAB due to redzoning, however SLAB disables redzoning for
  caches with alignment larger than unsigned long long.  Practically on at
  least x86 this includes kmalloc caches as they use cache line alignment,
  which is larger than that.  Still, this patch ensures alignment on all
  arches and cache sizes.

* SLUB layout is also unchanged unless redzoning is enabled through
  CONFIG_SLUB_DEBUG and boot parameter for the particular kmalloc cache.
  With this patch, explicit alignment is guaranteed with redzoning as
  well.  This will result in more memory being wasted, but that should be
  acceptable in a debugging scenario.

* SLOB has no implicit alignment so this patch adds it explicitly for
  kmalloc().  The potential downside is increased fragmentation.  While
  pathological allocation scenarios are certainly possible, in my testing,
  after booting a x86_64 kernel+userspace with virtme, around 16MB memory
  was consumed by slab pages both before and after the patch, with
  difference in the noise.

[1] https://lore.kernel.org/linux-btrfs/c3157c8e8e0e7588312b40c853f65c02fe6c957a.1566399731.git.christophe.leroy@c-s.fr/
[2] https://lore.kernel.org/linux-fsdevel/20190225040904.5557-1-ming.lei@redhat.com/
[3] https://lwn.net/Articles/787740/

[akpm@linux-foundation.org: documentation fixlet, per Matthew]
Link: http://lkml.kernel.org/r/20190826111627.7505-3-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: David Sterba <dsterba@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: "Darrick J . Wong" <darrick.wong@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
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>
2019-10-07 15:47:20 -07:00
Vlastimil Babka
6a486c0ad4 mm, sl[ou]b: improve memory accounting
Patch series "guarantee natural alignment for kmalloc()", v2.

This patch (of 2):

SLOB currently doesn't account its pages at all, so in /proc/meminfo the
Slab field shows zero.  Modifying a counter on page allocation and
freeing should be acceptable even for the small system scenarios SLOB is
intended for.  Since reclaimable caches are not separated in SLOB,
account everything as unreclaimable.

SLUB currently doesn't account kmalloc() and kmalloc_node() allocations
larger than order-1 page, that are passed directly to the page
allocator.  As they also don't appear in /proc/slabinfo, it might look
like a memory leak.  For consistency, account them as well.  (SLAB
doesn't actually use page allocator directly, so no change there).

Ideally SLOB and SLUB would be handled in separate patches, but due to
the shared kmalloc_order() function and different kfree()
implementations, it's easier to patch both at once to prevent
inconsistencies.

Link: http://lkml.kernel.org/r/20190826111627.7505-2-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: "Darrick J . Wong" <darrick.wong@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
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>
2019-10-07 15:47:20 -07:00
Chris Down
1bc63fb127 mm, memcg: make scan aggression always exclude protection
This patch is an incremental improvement on the existing
memory.{low,min} relative reclaim work to base its scan pressure
calculations on how much protection is available compared to the current
usage, rather than how much the current usage is over some protection
threshold.

This change doesn't change the experience for the user in the normal
case too much.  One benefit is that it replaces the (somewhat arbitrary)
100% cutoff with an indefinite slope, which makes it easier to ballpark
a memory.low value.

As well as this, the old methodology doesn't quite apply generically to
machines with varying amounts of physical memory.  Let's say we have a
top level cgroup, workload.slice, and another top level cgroup,
system-management.slice.  We want to roughly give 12G to
system-management.slice, so on a 32GB machine we set memory.low to 20GB
in workload.slice, and on a 64GB machine we set memory.low to 52GB.
However, because these are relative amounts to the total machine size,
while the amount of memory we want to generally be willing to yield to
system.slice is absolute (12G), we end up putting more pressure on
system.slice just because we have a larger machine and a larger workload
to fill it, which seems fairly unintuitive.  With this new behaviour, we
don't end up with this unintended side effect.

Previously the way that memory.low protection works is that if you are
50% over a certain baseline, you get 50% of your normal scan pressure.
This is certainly better than the previous cliff-edge behaviour, but it
can be improved even further by always considering memory under the
currently enforced protection threshold to be out of bounds.  This means
that we can set relatively low memory.low thresholds for variable or
bursty workloads while still getting a reasonable level of protection,
whereas with the previous version we may still trivially hit the 100%
clamp.  The previous 100% clamp is also somewhat arbitrary, whereas this
one is more concretely based on the currently enforced protection
threshold, which is likely easier to reason about.

There is also a subtle issue with the way that proportional reclaim
worked previously -- it promotes having no memory.low, since it makes
pressure higher during low reclaim.  This happens because we base our
scan pressure modulation on how far memory.current is between memory.min
and memory.low, but if memory.low is unset, we only use the overage
method.  In most cromulent configurations, this then means that we end
up with *more* pressure than with no memory.low at all when we're in low
reclaim, which is not really very usable or expected.

With this patch, memory.low and memory.min affect reclaim pressure in a
more understandable and composable way.  For example, from a user
standpoint, "protected" memory now remains untouchable from a reclaim
aggression standpoint, and users can also have more confidence that
bursty workloads will still receive some amount of guaranteed
protection.

Link: http://lkml.kernel.org/r/20190322160307.GA3316@chrisdown.name
Signed-off-by: Chris Down <chris@chrisdown.name>
Reviewed-by: Roman Gushchin <guro@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-07 15:47:20 -07:00
Chris Down
9de7ca46ad mm, memcg: make memory.emin the baseline for utilisation determination
Roman points out that when when we do the low reclaim pass, we scale the
reclaim pressure relative to position between 0 and the maximum
protection threshold.

However, if the maximum protection is based on memory.elow, and
memory.emin is above zero, this means we still may get binary behaviour
on second-pass low reclaim.  This is because we scale starting at 0, not
starting at memory.emin, and since we don't scan at all below emin, we
end up with cliff behaviour.

This should be a fairly uncommon case since usually we don't go into the
second pass, but it makes sense to scale our low reclaim pressure
starting at emin.

You can test this by catting two large sparse files, one in a cgroup
with emin set to some moderate size compared to physical RAM, and
another cgroup without any emin.  In both cgroups, set an elow larger
than 50% of physical RAM.  The one with emin will have less page
scanning, as reclaim pressure is lower.

Rebase on top of and apply the same idea as what was applied to handle
cgroup_memory=disable properly for the original proportional patch
http://lkml.kernel.org/r/20190201045711.GA18302@chrisdown.name ("mm,
memcg: Handle cgroup_disable=memory when getting memcg protection").

Link: http://lkml.kernel.org/r/20190201051810.GA18895@chrisdown.name
Signed-off-by: Chris Down <chris@chrisdown.name>
Suggested-by: Roman Gushchin <guro@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Dennis Zhou <dennis@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-07 15:47:20 -07:00
Chris Down
9783aa9917 mm, memcg: proportional memory.{low,min} reclaim
cgroup v2 introduces two memory protection thresholds: memory.low
(best-effort) and memory.min (hard protection).  While they generally do
what they say on the tin, there is a limitation in their implementation
that makes them difficult to use effectively: that cliff behaviour often
manifests when they become eligible for reclaim.  This patch implements
more intuitive and usable behaviour, where we gradually mount more
reclaim pressure as cgroups further and further exceed their protection
thresholds.

This cliff edge behaviour happens because we only choose whether or not
to reclaim based on whether the memcg is within its protection limits
(see the use of mem_cgroup_protected in shrink_node), but we don't vary
our reclaim behaviour based on this information.  Imagine the following
timeline, with the numbers the lruvec size in this zone:

1. memory.low=1000000, memory.current=999999. 0 pages may be scanned.
2. memory.low=1000000, memory.current=1000000. 0 pages may be scanned.
3. memory.low=1000000, memory.current=1000001. 1000001* pages may be
   scanned. (?!)

* Of course, we won't usually scan all available pages in the zone even
  without this patch because of scan control priority, over-reclaim
  protection, etc.  However, as shown by the tests at the end, these
  techniques don't sufficiently throttle such an extreme change in input,
  so cliff-like behaviour isn't really averted by their existence alone.

Here's an example of how this plays out in practice.  At Facebook, we are
trying to protect various workloads from "system" software, like
configuration management tools, metric collectors, etc (see this[0] case
study).  In order to find a suitable memory.low value, we start by
determining the expected memory range within which the workload will be
comfortable operating.  This isn't an exact science -- memory usage deemed
"comfortable" will vary over time due to user behaviour, differences in
composition of work, etc, etc.  As such we need to ballpark memory.low,
but doing this is currently problematic:

1. If we end up setting it too low for the workload, it won't have
   *any* effect (see discussion above).  The group will receive the full
   weight of reclaim and won't have any priority while competing with the
   less important system software, as if we had no memory.low configured
   at all.

2. Because of this behaviour, we end up erring on the side of setting
   it too high, such that the comfort range is reliably covered.  However,
   protected memory is completely unavailable to the rest of the system,
   so we might cause undue memory and IO pressure there when we *know* we
   have some elasticity in the workload.

3. Even if we get the value totally right, smack in the middle of the
   comfort zone, we get extreme jumps between no pressure and full
   pressure that cause unpredictable pressure spikes in the workload due
   to the current binary reclaim behaviour.

With this patch, we can set it to our ballpark estimation without too much
worry.  Any undesirable behaviour, such as too much or too little reclaim
pressure on the workload or system will be proportional to how far our
estimation is off.  This means we can set memory.low much more
conservatively and thus waste less resources *without* the risk of the
workload falling off a cliff if we overshoot.

As a more abstract technical description, this unintuitive behaviour
results in having to give high-priority workloads a large protection
buffer on top of their expected usage to function reliably, as otherwise
we have abrupt periods of dramatically increased memory pressure which
hamper performance.  Having to set these thresholds so high wastes
resources and generally works against the principle of work conservation.
In addition, having proportional memory reclaim behaviour has other
benefits.  Most notably, before this patch it's basically mandatory to set
memory.low to a higher than desirable value because otherwise as soon as
you exceed memory.low, all protection is lost, and all pages are eligible
to scan again.  By contrast, having a gradual ramp in reclaim pressure
means that you now still get some protection when thresholds are exceeded,
which means that one can now be more comfortable setting memory.low to
lower values without worrying that all protection will be lost.  This is
important because workingset size is really hard to know exactly,
especially with variable workloads, so at least getting *some* protection
if your workingset size grows larger than you expect increases user
confidence in setting memory.low without a huge buffer on top being
needed.

Thanks a lot to Johannes Weiner and Tejun Heo for their advice and
assistance in thinking about how to make this work better.

In testing these changes, I intended to verify that:

1. Changes in page scanning become gradual and proportional instead of
   binary.

   To test this, I experimented stepping further and further down
   memory.low protection on a workload that floats around 19G workingset
   when under memory.low protection, watching page scan rates for the
   workload cgroup:

   +------------+-----------------+--------------------+--------------+
   | memory.low | test (pgscan/s) | control (pgscan/s) | % of control |
   +------------+-----------------+--------------------+--------------+
   |        21G |               0 |                  0 | N/A          |
   |        17G |             867 |               3799 | 23%          |
   |        12G |            1203 |               3543 | 34%          |
   |         8G |            2534 |               3979 | 64%          |
   |         4G |            3980 |               4147 | 96%          |
   |          0 |            3799 |               3980 | 95%          |
   +------------+-----------------+--------------------+--------------+

   As you can see, the test kernel (with a kernel containing this
   patch) ramps up page scanning significantly more gradually than the
   control kernel (without this patch).

2. More gradual ramp up in reclaim aggression doesn't result in
   premature OOMs.

   To test this, I wrote a script that slowly increments the number of
   pages held by stress(1)'s --vm-keep mode until a production system
   entered severe overall memory contention.  This script runs in a highly
   protected slice taking up the majority of available system memory.
   Watching vmstat revealed that page scanning continued essentially
   nominally between test and control, without causing forward reclaim
   progress to become arrested.

[0]: https://facebookmicrosites.github.io/cgroup2/docs/overview.html#case-study-the-fbtax2-project

[akpm@linux-foundation.org: reflow block comments to fit in 80 cols]
[chris@chrisdown.name: handle cgroup_disable=memory when getting memcg protection]
  Link: http://lkml.kernel.org/r/20190201045711.GA18302@chrisdown.name
Link: http://lkml.kernel.org/r/20190124014455.GA6396@chrisdown.name
Signed-off-by: Chris Down <chris@chrisdown.name>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Roman Gushchin <guro@fb.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Dennis Zhou <dennis@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>
2019-10-07 15:47:20 -07:00
Dan Carpenter
518a867130 mm/vmpressure.c: fix a signedness bug in vmpressure_register_event()
The "mode" and "level" variables are enums and in this context GCC will
treat them as unsigned ints so the error handling is never triggered.

I also removed the bogus initializer because it isn't required any more
and it's sort of confusing.

[akpm@linux-foundation.org: reduce implicit and explicit typecasting]
[akpm@linux-foundation.org: fix return value, add comment, per Matthew]
Link: http://lkml.kernel.org/r/20190925110449.GO3264@mwanda
Fixes: 3cadfa2b94 ("mm/vmpressure.c: convert to use match_string() helper")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: David Rientjes <rientjes@google.com>
Reviewed-by: Matthew Wilcox <willy@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Enrico Weigelt <info@metux.net>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-07 15:47:19 -07:00
Qian Cai
234fdce892 mm/page_alloc.c: fix a crash in free_pages_prepare()
On architectures like s390, arch_free_page() could mark the page unused
(set_page_unused()) and any access later would trigger a kernel panic.
Fix it by moving arch_free_page() after all possible accessing calls.

 Hardware name: IBM 2964 N96 400 (z/VM 6.4.0)
 Krnl PSW : 0404e00180000000 0000000026c2b96e (__free_pages_ok+0x34e/0x5d8)
            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3
 Krnl GPRS: 0000000088d43af7 0000000000484000 000000000000007c 000000000000000f
            000003d080012100 000003d080013fc0 0000000000000000 0000000000100000
            00000000275cca48 0000000000000100 0000000000000008 000003d080010000
            00000000000001d0 000003d000000000 0000000026c2b78a 000000002717fdb0
 Krnl Code: 0000000026c2b95c: ec1100b30659 risbgn %r1,%r1,0,179,6
            0000000026c2b962: e32014000036 pfd 2,1024(%r1)
           #0000000026c2b968: d7ff10001000 xc 0(256,%r1),0(%r1)
           >0000000026c2b96e: 41101100  la %r1,256(%r1)
            0000000026c2b972: a737fff8  brctg %r3,26c2b962
            0000000026c2b976: d7ff10001000 xc 0(256,%r1),0(%r1)
            0000000026c2b97c: e31003400004 lg %r1,832
            0000000026c2b982: ebff1430016a asi 5168(%r1),-1
 Call Trace:
 __free_pages_ok+0x16a/0x5d8)
 memblock_free_all+0x206/0x290
 mem_init+0x58/0x120
 start_kernel+0x2b0/0x570
 startup_continue+0x6a/0xc0
 INFO: lockdep is turned off.
 Last Breaking-Event-Address:
 __free_pages_ok+0x372/0x5d8
 Kernel panic - not syncing: Fatal exception: panic_on_oops
 00: HCPGIR450W CP entered; disabled wait PSW 00020001 80000000 00000000 26A2379C

In the past, only kernel_poison_pages() would trigger this but it needs
"page_poison=on" kernel cmdline, and I suspect nobody tested that on
s390.  Recently, kernel_init_free_pages() (commit 6471384af2 ("mm:
security: introduce init_on_alloc=1 and init_on_free=1 boot options"))
was added and could trigger this as well.

[akpm@linux-foundation.org: add comment]
Link: http://lkml.kernel.org/r/1569613623-16820-1-git-send-email-cai@lca.pw
Fixes: 8823b1dbc0 ("mm/page_poison.c: enable PAGE_POISONING as a separate option")
Fixes: 6471384af2 ("mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options")
Signed-off-by: Qian Cai <cai@lca.pw>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Duyck <alexander.duyck@gmail.com>
Cc: <stable@vger.kernel.org>	[5.3+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-07 15:47:19 -07:00
Vitaly Wool
5b6807de11 mm/z3fold.c: claim page in the beginning of free
There's a really hard to reproduce race in z3fold between z3fold_free()
and z3fold_reclaim_page().  z3fold_reclaim_page() can claim the page
after z3fold_free() has checked if the page was claimed and
z3fold_free() will then schedule this page for compaction which may in
turn lead to random page faults (since that page would have been
reclaimed by then).

Fix that by claiming page in the beginning of z3fold_free() and not
forgetting to clear the claim in the end.

[vitalywool@gmail.com: v2]
  Link: http://lkml.kernel.org/r/20190928113456.152742cf@bigdell
Link: http://lkml.kernel.org/r/20190926104844.4f0c6efa1366b8f5741eaba9@gmail.com
Signed-off-by: Vitaly Wool <vitalywool@gmail.com>
Reported-by: Markus Linnala <markus.linnala@gmail.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Henry Burns <henrywolfeburns@gmail.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Markus Linnala <markus.linnala@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-07 15:47:19 -07:00
Michal Hocko
b0f53dbc4b kernel/sysctl.c: do not override max_threads provided by userspace
Partially revert 16db3d3f11 ("kernel/sysctl.c: threads-max observe
limits") because the patch is causing a regression to any workload which
needs to override the auto-tuning of the limit provided by kernel.

set_max_threads is implementing a boot time guesstimate to provide a
sensible limit of the concurrently running threads so that runaways will
not deplete all the memory.  This is a good thing in general but there
are workloads which might need to increase this limit for an application
to run (reportedly WebSpher MQ is affected) and that is simply not
possible after the mentioned change.  It is also very dubious to
override an admin decision by an estimation that doesn't have any direct
relation to correctness of the kernel operation.

Fix this by dropping set_max_threads from sysctl_max_threads so any
value is accepted as long as it fits into MAX_THREADS which is important
to check because allowing more threads could break internal robust futex
restriction.  While at it, do not use MIN_THREADS as the lower boundary
because it is also only a heuristic for automatic estimation and admin
might have a good reason to stop new threads to be created even when
below this limit.

This became more severe when we switched x86 from 4k to 8k kernel
stacks.  Starting since 6538b8ea88 ("x86_64: expand kernel stack to
16K") (3.16) we use THREAD_SIZE_ORDER = 2 and that halved the auto-tuned
value.

In the particular case

  3.12
  kernel.threads-max = 515561

  4.4
  kernel.threads-max = 200000

Neither of the two values is really insane on 32GB machine.

I am not sure we want/need to tune the max_thread value further.  If
anything the tuning should be removed altogether if proven not useful in
general.  But we definitely need a way to override this auto-tuning.

Link: http://lkml.kernel.org/r/20190922065801.GB18814@dhcp22.suse.cz
Fixes: 16db3d3f11 ("kernel/sysctl.c: threads-max observe limits")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Heinrich Schuchardt <xypron.glpk@gmx.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-07 15:47:19 -07:00
Baoquan He
08d1d0e6d0 memcg: only record foreign writebacks with dirty pages when memcg is not disabled
In kdump kernel, memcg usually is disabled with 'cgroup_disable=memory'
for saving memory.  Now kdump kernel will always panic when dump vmcore
to local disk:

  BUG: kernel NULL pointer dereference, address: 0000000000000ab8
  Oops: 0000 [#1] SMP NOPTI
  CPU: 0 PID: 598 Comm: makedumpfile Not tainted 5.3.0+ #26
  Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 10/02/2018
  RIP: 0010:mem_cgroup_track_foreign_dirty_slowpath+0x38/0x140
  Call Trace:
   __set_page_dirty+0x52/0xc0
   iomap_set_page_dirty+0x50/0x90
   iomap_write_end+0x6e/0x270
   iomap_write_actor+0xce/0x170
   iomap_apply+0xba/0x11e
   iomap_file_buffered_write+0x62/0x90
   xfs_file_buffered_aio_write+0xca/0x320 [xfs]
   new_sync_write+0x12d/0x1d0
   vfs_write+0xa5/0x1a0
   ksys_write+0x59/0xd0
   do_syscall_64+0x59/0x1e0
   entry_SYSCALL_64_after_hwframe+0x44/0xa9

And this will corrupt the 1st kernel too with 'cgroup_disable=memory'.

Via the trace and with debugging, it is pointing to commit 97b27821b4
("writeback, memcg: Implement foreign dirty flushing") which introduced
this regression.  Disabling memcg causes the null pointer dereference at
uninitialized data in function mem_cgroup_track_foreign_dirty_slowpath().

Fix it by returning directly if memcg is disabled, but not trying to
record the foreign writebacks with dirty pages.

Link: http://lkml.kernel.org/r/20190924141928.GD31919@MiWiFi-R3L-srv
Fixes: 97b27821b4 ("writeback, memcg: Implement foreign dirty flushing")
Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-07 15:47:19 -07:00
Yi Wang
758b8db4a5 mm: fix -Wmissing-prototypes warnings
We get two warnings when build kernel W=1:

  mm/shuffle.c:36:12: warning: no previous prototype for `shuffle_show' [-Wmissing-prototypes]
  mm/sparse.c:220:6: warning: no previous prototype for `subsection_mask_set' [-Wmissing-prototypes]

Make the functions static to fix this.

Link: http://lkml.kernel.org/r/1566978161-7293-1-git-send-email-wang.yi59@zte.com.cn
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-07 15:47:19 -07:00
Tejun Heo
8e00c4e9dd writeback: fix use-after-free in finish_writeback_work()
finish_writeback_work() reads @done->waitq after decrementing
@done->cnt.  However, once @done->cnt reaches zero, @done may be freed
(from stack) at any moment and @done->waitq can contain something
unrelated by the time finish_writeback_work() tries to read it.  This
led to the following crash.

  "BUG: kernel NULL pointer dereference, address: 0000000000000002"
  #PF: supervisor write access in kernel mode
  #PF: error_code(0x0002) - not-present page
  PGD 0 P4D 0
  Oops: 0002 [#1] SMP DEBUG_PAGEALLOC
  CPU: 40 PID: 555153 Comm: kworker/u98:50 Kdump: loaded Not tainted
  ...
  Workqueue: writeback wb_workfn (flush-btrfs-1)
  RIP: 0010:_raw_spin_lock_irqsave+0x10/0x30
  Code: 48 89 d8 5b c3 e8 50 db 6b ff eb f4 0f 1f 40 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 53 9c 5b fa 31 c0 ba 01 00 00 00 <f0> 0f b1 17 75 05 48 89 d8 5b c3 89 c6 e8 fe ca 6b ff eb f2 66 90
  RSP: 0018:ffffc90049b27d98 EFLAGS: 00010046
  RAX: 0000000000000000 RBX: 0000000000000246 RCX: 0000000000000000
  RDX: 0000000000000001 RSI: 0000000000000003 RDI: 0000000000000002
  RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001
  R10: ffff889fff407600 R11: ffff88ba9395d740 R12: 000000000000e300
  R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000000000
  FS:  0000000000000000(0000) GS:ffff88bfdfa00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000002 CR3: 0000000002409005 CR4: 00000000001606e0
  Call Trace:
   __wake_up_common_lock+0x63/0xc0
   wb_workfn+0xd2/0x3e0
   process_one_work+0x1f5/0x3f0
   worker_thread+0x2d/0x3d0
   kthread+0x111/0x130
   ret_from_fork+0x1f/0x30

Fix it by reading and caching @done->waitq before decrementing
@done->cnt.

Link: http://lkml.kernel.org/r/20190924010631.GH2233839@devbig004.ftw2.facebook.com
Fixes: 5b9cce4c7e ("writeback: Generalize and expose wb_completion")
Signed-off-by: Tejun Heo <tj@kernel.org>
Debugged-by: Chris Mason <clm@fb.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: <stable@vger.kernel.org>	[5.2+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-07 15:47:19 -07:00
Anshuman Khandual
6d0e984941 mm/memremap: drop unused SECTION_SIZE and SECTION_MASK
SECTION_SIZE and SECTION_MASK macros are not getting used anymore.  But
they do conflict with existing definitions on arm64 platform causing
following warning during build.  Lets drop these unused macros.

  mm/memremap.c:16: warning: "SECTION_MASK" redefined
   #define SECTION_MASK ~((1UL << PA_SECTION_SHIFT) - 1)
  arch/arm64/include/asm/pgtable-hwdef.h:79: note: this is the location of the previous definition
   #define SECTION_MASK  (~(SECTION_SIZE-1))

  mm/memremap.c:17: warning: "SECTION_SIZE" redefined
   #define SECTION_SIZE (1UL << PA_SECTION_SHIFT)
  arch/arm64/include/asm/pgtable-hwdef.h:78: note: this is the location of the previous definition
   #define SECTION_SIZE  (_AC(1, UL) << SECTION_SHIFT)

Link: http://lkml.kernel.org/r/1569312010-31313-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reported-by: kbuild test robot <lkp@intel.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-07 15:47:19 -07:00
Will Deacon
20bb759a66 panic: ensure preemption is disabled during panic()
Calling 'panic()' on a kernel with CONFIG_PREEMPT=y can leave the
calling CPU in an infinite loop, but with interrupts and preemption
enabled.  From this state, userspace can continue to be scheduled,
despite the system being "dead" as far as the kernel is concerned.

This is easily reproducible on arm64 when booting with "nosmp" on the
command line; a couple of shell scripts print out a periodic "Ping"
message whilst another triggers a crash by writing to
/proc/sysrq-trigger:

  | sysrq: Trigger a crash
  | Kernel panic - not syncing: sysrq triggered crash
  | CPU: 0 PID: 1 Comm: init Not tainted 5.2.15 #1
  | Hardware name: linux,dummy-virt (DT)
  | Call trace:
  |  dump_backtrace+0x0/0x148
  |  show_stack+0x14/0x20
  |  dump_stack+0xa0/0xc4
  |  panic+0x140/0x32c
  |  sysrq_handle_reboot+0x0/0x20
  |  __handle_sysrq+0x124/0x190
  |  write_sysrq_trigger+0x64/0x88
  |  proc_reg_write+0x60/0xa8
  |  __vfs_write+0x18/0x40
  |  vfs_write+0xa4/0x1b8
  |  ksys_write+0x64/0xf0
  |  __arm64_sys_write+0x14/0x20
  |  el0_svc_common.constprop.0+0xb0/0x168
  |  el0_svc_handler+0x28/0x78
  |  el0_svc+0x8/0xc
  | Kernel Offset: disabled
  | CPU features: 0x0002,24002004
  | Memory Limit: none
  | ---[ end Kernel panic - not syncing: sysrq triggered crash ]---
  |  Ping 2!
  |  Ping 1!
  |  Ping 1!
  |  Ping 2!

The issue can also be triggered on x86 kernels if CONFIG_SMP=n,
otherwise local interrupts are disabled in 'smp_send_stop()'.

Disable preemption in 'panic()' before re-enabling interrupts.

Link: http://lkml.kernel.org/r/20191002123538.22609-1-will@kernel.org
Link: https://lore.kernel.org/r/BX1W47JXPMR8.58IYW53H6M5N@dragonstone
Signed-off-by: Will Deacon <will@kernel.org>
Reported-by: Xogium <contact@xogium.me>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Feng Tang <feng.tang@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>
2019-10-07 15:47:19 -07:00
Jia-Ju Bai
2abb7d3b12 fs: ocfs2: fix a possible null-pointer dereference in ocfs2_info_scan_inode_alloc()
In ocfs2_info_scan_inode_alloc(), there is an if statement on line 283
to check whether inode_alloc is NULL:

    if (inode_alloc)

When inode_alloc is NULL, it is used on line 287:

    ocfs2_inode_lock(inode_alloc, &bh, 0);
        ocfs2_inode_lock_full_nested(inode, ...)
            struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);

Thus, a possible null-pointer dereference may occur.

To fix this bug, inode_alloc is checked on line 286.

This bug is found by a static analysis tool STCheck written by us.

Link: http://lkml.kernel.org/r/20190726033717.32359-1-baijiaju1990@gmail.com
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-07 15:47:19 -07:00
Jia-Ju Bai
583fee3e12 fs: ocfs2: fix a possible null-pointer dereference in ocfs2_write_end_nolock()
In ocfs2_write_end_nolock(), there are an if statement on lines 1976,
2047 and 2058, to check whether handle is NULL:

    if (handle)

When handle is NULL, it is used on line 2045:

	ocfs2_update_inode_fsync_trans(handle, inode, 1);
        oi->i_sync_tid = handle->h_transaction->t_tid;

Thus, a possible null-pointer dereference may occur.

To fix this bug, handle is checked before calling
ocfs2_update_inode_fsync_trans().

This bug is found by a static analysis tool STCheck written by us.

Link: http://lkml.kernel.org/r/20190726033705.32307-1-baijiaju1990@gmail.com
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-07 15:47:19 -07:00
Jia-Ju Bai
56e94ea132 fs: ocfs2: fix possible null-pointer dereferences in ocfs2_xa_prepare_entry()
In ocfs2_xa_prepare_entry(), there is an if statement on line 2136 to
check whether loc->xl_entry is NULL:

    if (loc->xl_entry)

When loc->xl_entry is NULL, it is used on line 2158:

    ocfs2_xa_add_entry(loc, name_hash);
        loc->xl_entry->xe_name_hash = cpu_to_le32(name_hash);
        loc->xl_entry->xe_name_offset = cpu_to_le16(loc->xl_size);

and line 2164:

    ocfs2_xa_add_namevalue(loc, xi);
        loc->xl_entry->xe_value_size = cpu_to_le64(xi->xi_value_len);
        loc->xl_entry->xe_name_len = xi->xi_name_len;

Thus, possible null-pointer dereferences may occur.

To fix these bugs, if loc-xl_entry is NULL, ocfs2_xa_prepare_entry()
abnormally returns with -EINVAL.

These bugs are found by a static analysis tool STCheck written by us.

[akpm@linux-foundation.org: remove now-unused ocfs2_xa_add_entry()]
Link: http://lkml.kernel.org/r/20190726101447.9153-1-baijiaju1990@gmail.com
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-07 15:47:19 -07:00
Jia Guo
7a243c82ea ocfs2: clear zero in unaligned direct IO
Unused portion of a part-written fs-block-sized block is not set to zero
in unaligned append direct write.This can lead to serious data
inconsistencies.

Ocfs2 manage disk with cluster size(for example, 1M), part-written in
one cluster will change the cluster state from UN-WRITTEN to WRITTEN,
VFS(function dio_zero_block) doesn't do the cleaning because bh's state
is not set to NEW in function ocfs2_dio_wr_get_block when we write a
WRITTEN cluster.  For example, the cluster size is 1M, file size is 8k
and we direct write from 14k to 15k, then 12k~14k and 15k~16k will
contain dirty data.

We have to deal with two cases:
 1.The starting position of direct write is outside the file.
 2.The starting position of direct write is located in the file.

We need set bh's state to NEW in the first case.  In the second case, we
need mapped twice because bh's state of area out file should be set to
NEW while area in file not.

[akpm@linux-foundation.org: coding style fixes]
Link: http://lkml.kernel.org/r/5292e287-8f1a-fd4a-1a14-661e555e0bed@huawei.com
Signed-off-by: Jia Guo <guojia12@huawei.com>
Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-07 15:47:19 -07:00
Boris Ostrovsky
c6875f3aac x86/xen: Return from panic notifier
Currently execution of panic() continues until Xen's panic notifier
(xen_panic_event()) is called at which point we make a hypercall that
never returns.

This means that any notifier that is supposed to be called later as
well as significant part of panic() code (such as pstore writes from
kmsg_dump()) is never executed.

There is no reason for xen_panic_event() to be this last point in
execution since panic()'s emergency_restart() will call into
xen_emergency_restart() from where we can perform our hypercall.

Nevertheless, we will provide xen_legacy_crash boot option that will
preserve original behavior during crash. This option could be used,
for example, if running kernel dumper (which happens after panic
notifiers) is undesirable.

Reported-by: James Dingwall <james@dingwall.me.uk>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
2019-10-07 17:53:30 -04:00
Vincent Chen
8bb0daef64 riscv: Correct the handling of unexpected ebreak in do_trap_break()
For the kernel space, all ebreak instructions are determined at compile
time because the kernel space debugging module is currently unsupported.
Hence, it should be treated as a bug if an ebreak instruction which does
not belong to BUG_TRAP_TYPE_WARN or BUG_TRAP_TYPE_BUG is executed in
kernel space. For the userspace, debugging module or user problem may
intentionally insert an ebreak instruction to trigger a SIGTRAP signal.
To approach the above two situations, the do_trap_break() will direct
the BUG_TRAP_TYPE_NONE ebreak exception issued in kernel space to die()
and will send a SIGTRAP to the trapped process only when the ebreak is
in userspace.

Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
[paul.walmsley@sifive.com: fixed checkpatch issue]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-10-07 12:59:41 -07:00
Vincent Chen
e0c0fc18f1 riscv: avoid sending a SIGTRAP to a user thread trapped in WARN()
On RISC-V, when the kernel runs code on behalf of a user thread, and the
kernel executes a WARN() or WARN_ON(), the user thread will be sent
a bogus SIGTRAP.  Fix the RISC-V kernel code to not send a SIGTRAP when
a WARN()/WARN_ON() is executed.

Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
[paul.walmsley@sifive.com: fixed subject]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-10-07 12:59:40 -07:00
Vincent Chen
8b04825ed2 riscv: avoid kernel hangs when trapped in BUG()
When the CONFIG_GENERIC_BUG is disabled by disabling CONFIG_BUG, if a
kernel thread is trapped by BUG(), the whole system will be in the
loop that infinitely handles the ebreak exception instead of entering the
die function. To fix this problem, the do_trap_break() will always call
the die() to deal with the break exception as the type of break is
BUG_TRAP_TYPE_BUG.

Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-10-07 12:59:40 -07:00
Linus Torvalds
c512c69187 uaccess: implement a proper unsafe_copy_to_user() and switch filldir over to it
In commit 9f79b78ef7 ("Convert filldir[64]() from __put_user() to
unsafe_put_user()") I made filldir() use unsafe_put_user(), which
improves code generation on x86 enormously.

But because we didn't have a "unsafe_copy_to_user()", the dirent name
copy was also done by hand with unsafe_put_user() in a loop, and it
turns out that a lot of other architectures didn't like that, because
unlike x86, they have various alignment issues.

Most non-x86 architectures trap and fix it up, and some (like xtensa)
will just fail unaligned put_user() accesses unconditionally.  Which
makes that "copy using put_user() in a loop" not work for them at all.

I could make that code do explicit alignment etc, but the architectures
that don't like unaligned accesses also don't really use the fancy
"user_access_begin/end()" model, so they might just use the regular old
__copy_to_user() interface.

So this commit takes that looping implementation, turns it into the x86
version of "unsafe_copy_to_user()", and makes other architectures
implement the unsafe copy version as __copy_to_user() (the same way they
do for the other unsafe_xyz() accessor functions).

Note that it only does this for the copying _to_ user space, and we
still don't have a unsafe version of copy_from_user().

That's partly because we have no current users of it, but also partly
because the copy_from_user() case is slightly different and cannot
efficiently be implemented in terms of a unsafe_get_user() loop (because
gcc can't do asm goto with outputs).

It would be trivial to do this using "rep movsb", which would work
really nicely on newer x86 cores, but really badly on some older ones.

Al Viro is looking at cleaning up all our user copy routines to make
this all a non-issue, but for now we have this simple-but-stupid version
for x86 that works fine for the dirent name copy case because those
names are short strings and we simply don't need anything fancier.

Fixes: 9f79b78ef7 ("Convert filldir[64]() from __put_user() to unsafe_put_user()")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Reported-and-tested-by: Tony Luck <tony.luck@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-07 12:56:48 -07:00
Chris Wilson
b925708f28 drm/i915: Mark contents as dirty on a write fault
Since dropping the set-to-gtt-domain in commit a679f58d05 ("drm/i915:
Flush pages on acquisition"), we no longer mark the contents as dirty on
a write fault. This has the issue of us then not marking the pages as
dirty on releasing the buffer, which means the contents are not written
out to the swap device (should we ever pick that buffer as a victim).
Notably, this is visible in the dumb buffer interface used for cursors.
Having updated the cursor contents via mmap, and swapped away, if the
shrinker should evict the old cursor, upon next reuse, the cursor would
be invisible.

E.g. echo 80 > /proc/sys/kernel/sysrq ; echo f > /proc/sysrq-trigger

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111541
Fixes: a679f58d05 ("drm/i915: Flush pages on acquisition")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.william.auld@gmail.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: <stable@vger.kernel.org> # v5.2+
Reviewed-by: Matthew Auld <matthew.william.auld@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190920121821.7223-1-chris@chris-wilson.co.uk
(cherry picked from commit 5028851cdf)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
2019-10-07 10:44:52 -07:00