git.monstr.eu Git - linux-2.6-microblaze.git/log

mm: check that mm is still valid in madvise()

IORING_OP_MADVISE can end up basically doing mprotect() on the VM of
another process, which means that it can race with our crazy core dump
handling which accesses the VM state without holding the mmap_sem
(because it incorrectly thinks that it is the final user).

This is clearly a core dumping problem, but we've never fixed it the
right way, and instead have the notion of "check that the mm is still
ok" using mmget_still_valid() after getting the mmap_sem for writing in
any situation where we're not the original VM thread.

See commit 04f5866e41fb ("coredump: fix race condition between
mmget_not_zero()/get_task_mm() and core dumping") for more background on
this whole mmget_still_valid() thing. You might want to have a barf bag
handy when you do.

We're discussing just fixing this properly in the only remaining core
dumping routines. But even if we do that, let's make do_madvise() do
the right thing, and then when we fix core dumping, we can remove all
these mmget_still_valid() checks.

Reported-and-tested-by: Jann Horn <jannh@google.com>
Fixes: c1ca757bd6f4 ("io_uring: add IORING_OP_MADVISE")
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'io_uring-5.7-2020-04-24' of git://git.kernel.dk/linux-block

Pull io_uring fix from Jens Axboe:
"Single fixup for a change that went into -rc2"

* tag 'io_uring-5.7-2020-04-24' of git://git.kernel.dk/linux-block:
io_uring: only restore req->work for req that needs do completion

Merge tag 'libata-5.7-2020-04-24' of git://git.kernel.dk/linux-block

Pull libata fixlet from Jens Axboe:
"Minor spelling error fix for libata"

* tag 'libata-5.7-2020-04-24' of git://git.kernel.dk/linux-block:
ata: sata_inic162x fix a spelling issue

Merge tag 'block-5.7-2020-04-24' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
"A few fixes/changes that should go into this release:

   - null_blk zoned fixes (Damien)

   - blkdev_close() sync improvement (Douglas)

   - Fix regression in blk-iocost that impacted (at least) systemtap
     (Waiman)

   - Comment fix, header removal (Zhiqiang, Jianpeng)"

* tag 'block-5.7-2020-04-24' of git://git.kernel.dk/linux-block:
  null_blk: Cleanup zoned device initialization
  null_blk: Fix zoned command handling
  block: remove unused header
  blk-iocost: Fix error on iocost_ioc_vrate_adj
  bdev: Reduce time holding bd_mutex in sync in blkdev_close()
  buffer: remove useless comment and WB_REASON_FREE_MORE_MEM, reason.

Merge tag 'trace-v5.7-rc2' of git://git./linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
"A few tracing fixes:

   - Two fixes for memory leaks detected by kmemleak

   - Removal of some dead code

   - A few local functions turned static"

* tag 'trace-v5.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Convert local functions in tracing_map.c to static
  tracing: Remove DECLARE_TRACE_NOARGS
  ftrace: Fix memory leak caused by not freeing entry in unregister_ftrace_direct()
  tracing: Fix memory leaks in trace_events_hist.c

Merge tag 'arm64-fixes' of git://git./linux/kernel/git/arm64/linux

Pull arm64 fixes from Catalin Marinas:

- Ensure context synchronisation after a write to APIAKey.

- Fix bullet list formatting in Documentation/arm64/amu.rst to
   eliminate doc warnings.

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  Documentation: arm64: fix amu.rst doc warnings
  arm64: sync kernel APIAKey when installing

Merge tag 'kbuild-fixes-v5.7' of git://git./linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

- fix scripts/config to properly handle ':' in string type CONFIG
   options

- fix unneeded rebuilds of DT schema check rule

- git rid of ordering dependency between <linux/vermagic.h> and
   <linux/module.h> to fix build errors in some network drivers

- clean up generated headers of host arch with 'make ARCH=um mrproper'

* tag 'kbuild-fixes-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  h8300: ignore vmlinux.lds
  Documentation: kbuild: fix the section title format
  um: ensure `make ARCH=um mrproper` removes arch/$(SUBARCH)/include/generated/
  arch: split MODULE_ARCH_VERMAGIC definitions out to <asm/vermagic.h>
  kbuild: fix DT binding schema rule again to avoid needless rebuilds
  scripts/config: allow colons in option strings for sed

Merge tag 'afs-fixes-20200424' of git://git./linux/kernel/git/dhowells/linux-fs

Pull misc AFS fixes from David Howells:
"Three miscellaneous fixes to the afs filesystem:

   - Remove some struct members that aren't used, aren't set or aren't
     read, plus a wake up that nothing ever waits for.

   - Actually set the AFS_SERVER_FL_HAVE_EPOCH flag so that the code
     that depends on it can work.

   - Make a couple of waits uninterruptible if they're done for an
     operation that isn't supposed to be interruptible"

* tag 'afs-fixes-20200424' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Make record checking use TASK_UNINTERRUPTIBLE when appropriate
  afs: Fix to actually set AFS_SERVER_FL_HAVE_EPOCH
  afs: Remove some unused bits

Merge tag 'sound-5.7-rc3' of git://git./linux/kernel/git/tiwai/sound

Pull sound fixes from Takashi Iwai:
"This became a slightly big pull request, as the accumulated ASoC fixes
  are included here. Some highlights:

   - Revert of ASoC DAI startup changes that caused regression on some
     x86 platforms

   - Regression fix in HD-audio power management and driver blacklist

   - A collection of ASoC DAPM and topology fixes

   - Continued USB-audio fixes and quirks

   - Lots of small device-specific fixes

   - Rockchip S/PDIF DT stuff update for validation issues"

* tag 'sound-5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (51 commits)
  ALSA: hda: Always use jackpoll helper for jack update after resume
  ALSA: hda/realtek - Add new codec supported for ALC245
  ALSA: usb-audio: Fix usb audio refcnt leak when getting spdif
  ALSA: usb-audio: Add connector notifier delegation
  ALSA: usb-audio: Apply async workaround for Scarlett 2i4 2nd gen
  ASoC: wm8960: Fix wrong clock after suspend & resume
  ALSA: usx2y: Fix potential NULL dereference
  ALSA: usb-audio: Add quirk for Focusrite Scarlett 2i2
  ASoC: wm89xx: Add missing dependency
  ASoC: dapm: fixup dapm kcontrol widget
  ASoC: rsnd: Fix "status check failed" spam for multi-SSI
  ASoC: rsnd: Don't treat master SSI in multi SSI setup as parent
  ASoC: meson: gx-card: fix codec-to-codec link setup
  ASoC: meson: axg-card: fix codec-to-codec link setup
  ALSA: usb-audio: Add static mapping table for ALC1220-VB-based mobos
  ALSA: hda: Remove ASUS ROG Zenith from the blacklist
  ALSA: hda/realtek - Fix unexpected init_amp override
  ALSA: usb-audio: Filter out unsupported sample rates on Focusrite devices
  ASoC: SOF: Intel: add min/max channels for SSP on Baytrail/Broadwell
  ASoC: stm32: sai: fix sai probe
  ...

Merge tag 'drm-fixes-2020-04-24' of git://anongit.freedesktop.org/drm/drm

Pull drm fixes from Dave Airlie:
"Weekly regular fixes for drm, The usual rc3 uptick here, but nothing
  too crazy or notable.

  core:
   - mst: zero pbn when releasing vcpi slots

  amdgpu:
   - Fix resume issue on renoir
   - Thermal fix for older CI dGPUs
   - Fix some fallout from dropping drm load/unload callbacks

  i915:
   - Tigerlake Workaround - disabling media recompression (Matt)
   - Fix RPS interrupts for right GPU frequency (Chris)
   - HDCP fix prime check (Oliver)
   - Tigerlake Thunderbolt power well fix (Matt)
   - Tigerlake DP link training fixes (Jose)
   - Documentation sphinx build fix (Jani)
   - Fix enable_dpcd_backlight modparam (Lyude)

  analogix-dp:
   - binding fix

  meson:
   - remove unneeded error message

  bindings:
   - fix warnings
   - fix lvds binding

  scheduler:
   - thread racing fix

  tidss:
   - use after free fix"

* tag 'drm-fixes-2020-04-24' of git://anongit.freedesktop.org/drm/drm:
  drm/i915/dpcd_bl: Unbreak enable_dpcd_backlight modparam
  drm/i915: fix Sphinx build duplicate label warning
  drm/i915/display: Load DP_TP_CTL/STATUS offset before use it
  drm/i915/tgl: TBT AUX should use TC power well ops
  drm/i915: HDCP: fix Ri prime check done during link check
  drm/i915/gt: Update PMINTRMSK holding fw
  drm/i915/tgl: Add Wa_14010477008:tgl
  drm/tidss: fix crash related to accessing freed memory
  drm/dp_mst: Zero assigned PBN when releasing VCPI slots
  drm/amdgpu/display: give aux i2c buses more meaningful names
  drm/amdgpu/display: fix aux registration (v2)
  drm/amdgpu: Correctly initialize thermal controller for GPUs with Powerplay table v0 (e.g Hawaii)
  drm/amd/powerplay: fix resume failed as smu table initialize early exit
  drm/scheduler: fix drm_sched_get_cleanup_job
  drm/meson: Delete an error message in meson_dw_hdmi_bind()
  drm/bridge: anx6345: set correct BPC for display_info of connector
  dt-bindings: display: allow port and ports in panel-lvds
  dt-bindings: display: xpp055c272: Remove the reg property
  dt-bindings: display: ltk500hd1829: Remove the reg property
  drm/bridge: analogix_dp: Split bind() into probe() and real bind()

afs: Make record checking use TASK_UNINTERRUPTIBLE when appropriate

When an operation is meant to be done uninterruptibly (such as
FS.StoreData), we should not be allowing volume and server record checking
to be interrupted.

Fixes: d2ddc776a458 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: David Howells <dhowells@redhat.com>

afs: Fix to actually set AFS_SERVER_FL_HAVE_EPOCH

AFS keeps track of the epoch value from the rxrpc protocol to note (a) when
a fileserver appears to have restarted and (b) when different endpoints of
a fileserver do not appear to be associated with the same fileserver
(ie. all probes back from a fileserver from all of its interfaces should
carry the same epoch).

However, the AFS_SERVER_FL_HAVE_EPOCH flag that indicates that we've
received the server's epoch is never set, though it is used.

Fix this to set the flag when we first receive an epoch value from a probe
sent to the filesystem client from the fileserver.

Fixes: 3bf0fb6f33dd ("afs: Probe multiple fileservers simultaneously")
Signed-off-by: David Howells <dhowells@redhat.com>

afs: Remove some unused bits

Remove three bits:

(1) afs_server::no_epoch is neither set nor used.

(2) afs_server::have_result is set and a wakeup is applied to it, but
nothing looks at it or waits on it.

(3) afs_vl_dump_edestaddrreq() prints afs_addr_list::probed, but nothing
sets it for VL servers.

Signed-off-by: David Howells <dhowells@redhat.com>

Merge tag 'drm-misc-fixes-2020-04-23' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes

A few resources-related fixes (tidss, dp_mst, scheduler), probe fixes and
DT bindings adjustments.

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200423103224.7hvyr3v7dmuny2bz@gilmour.lan

Merge tag 'drm-intel-fixes-2020-04-23' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes

- Tigerlake Workaround - disabling media recompression (Matt)
- Fix RPS interrupts for right GPU frequency (Chris)
- HDCP fix prime check (Oliver)
- Tigerlake Thunderbolt power well fix (Matt)
- Tigerlake DP link training fixes (Jose)
- Documentation sphinx build fix (Jani)
- Fix enable_dpcd_backlight modparam (Lyude)

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200423190246.GA1710303@intel.com

Merge tag 'amd-drm-fixes-5.7-2020-04-22' of git://people.freedesktop.org/~agd5f/linux into drm-fixes

amd-drm-fixes-5.7-2020-04-22:

amdgpu:
- Fix resume issue on renoir
- Thermal fix for older CI dGPUs
- Fix some fallout from dropping drm load/unload callbacks

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexdeucher@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200422224647.617724-1-alexander.deucher@amd.com

Merge branch 'for-linus' of git://git./linux/kernel/git/ebiederm/user-namespace

Pull SIGCHLD fix from Eric Biederman:
"Christof Meerwald reported that do_notify_parent has not been
  successfully populating si_pid and si_uid for multi-threaded
  processes.

  This is the one-liner fix. Strictly speaking a one-liner plus
  comment"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  signal: Avoid corrupting si_pid and si_uid in do_notify_parent

Merge tag 'pci-v5.7-fixes-1' of git://git./linux/kernel/git/helgaas/pci

Pull PCI fixes from Bjorn Helgaas:

- Workaround Apex TPU class code issue that prevents resource
   assignment (Bjorn Helgaas)

- Update MAINTAINERS to add Rob Herring for native PCI controller
   drivers (Lorenzo Pieralisi)

* tag 'pci-v5.7-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  MAINTAINERS: Add Rob Herring and remove Andy Murray as PCI reviewers
  PCI: Move Apex Edge TPU class quirk to fix BAR assignment

Merge tag 'armsoc-fixes' of git://git./linux/kernel/git/soc/soc

Pull ARM SoC fixes from Arnd Bergmann:
"A few smaller fixes for v5.7-rc3: The majority are fixes for bugs I
  found after restarting my randconfig build testing that had been
  dormant for a while.

  On the Nokia N950/N9 phone, a DT fix is required to address a boot
  regression.

  For the bcm283x (Raspberry Pi), two DT fixes address minor issues"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
  soc: imx8: select SOC_BUS
  soc: tegra: fix tegra_pmc_get_suspend_mode definition
  soc: fsl: dpio: avoid stack usage warning
  soc: fsl: dpio: fix incorrect pointer conversions
  ARM: imx: provide v7_cpu_resume() only on ARM_CPU_SUSPEND=y
  ARM: dts: bcm283x: Disable dsi0 node
  firmware: xilinx: make firmware_debugfs_root static
  drivers: soc: xilinx: fix firmware driver Kconfig dependency
  ARM: dts: bcm283x: Add cells encoding format to firmware bus
  ARM: dts: OMAP3: disable RNG on N950/N9

Merge tag 'nfsd-5.7-rc-1' of git://git.linux-nfs.org/projects/cel/cel-2.6

Pull nfsd fixes from Chuck Lever:
"The first set of 5.7-rc fixes for NFS server issues.

  These were all unresolved at the time the 5.7 window opened, and
  needed some additional time to ensure they were correctly addressed.
  They are ready now.

  At the moment I know of one more urgent issue regarding the NFS
  server. A fix has been tested and is under review. I expect to send
  one more pull request, containing this fix (which now consists of 3
  patches).

  Fixes:

   - Address several use-after-free and memory leak bugs

   - Prevent a backchannel livelock"

* tag 'nfsd-5.7-rc-1' of git://git.linux-nfs.org/projects/cel/cel-2.6:
  svcrdma: Fix leak of svc_rdma_recv_ctxt objects
  svcrdma: Fix trace point use-after-free race
  SUNRPC: Fix backchannel RPC soft lockups
  SUNRPC/cache: Fix unsafe traverse caused double-free in cache_purge
  nfsd: memory corruption in nfsd4_lock()

Merge tag 'for-5.7-rc3' of git://git./linux/kernel/git/linkinjeon/exfat

Pull exfat fixes from Namjae Jeon:

- several bug fixes(broken mount discard option, remount failure,
   memory leak)

- add missing MODULE_ALIAS_FS for automatically loading exfat module.

- set s_time_gran and truncate atime with exfat timestamp granularity.

* tag 'for-5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat:
  exfat: truncate atimes to 2s granularity
  exfat: properly set s_time_gran
  exfat: remove 'bps' mount-option
  exfat: Unify access to the boot sector
  exfat: add missing MODULE_ALIAS_FS()
  exfat: Fix discard support

Merge tag 'rproc-v5.7-fixes' of git://git./linux/kernel/git/andersson/remoteproc

Pull remoteproc fixes from Bjorn Andersson:
"This fixes a regression in the probe error path of the Qualcomm modem
  remoteproc driver and a mix up of phy_addr_t and dma_addr_t in the
  Mediatek SCP control driver"

* tag 'rproc-v5.7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/andersson/remoteproc:
  remoteproc: mtk_scp: use dma_addr_t for DMA API
  remoteproc: qcom_q6v5_mss: fix q6v5_probe() error paths
  remoteproc: qcom_q6v5_mss: fix a bug in q6v5_probe()

Merge tag 'audit-pr-20200422' of git://git./linux/kernel/git/pcmoore/audit

Pull audit fix from Paul Moore:
"One small audit patch fix, fixing a missing length check on input from
userspace, nothing crazy"

* tag 'audit-pr-20200422' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
audit: check the length of userspace generated audit records

Documentation: arm64: fix amu.rst doc warnings

Fix bullet list formatting to eliminate doc warnings:

Documentation/arm64/amu.rst:26: WARNING: Unexpected indentation.
Documentation/arm64/amu.rst:60: WARNING: Unexpected indentation.
Documentation/arm64/amu.rst:81: WARNING: Unexpected indentation.
Documentation/arm64/amu.rst:108: WARNING: Unexpected indentation.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Ionela Voinescu <ionela.voinescu@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

ata: sata_inic162x fix a spelling issue

Fixed a warning message spelling issue.

Signed-off-by: John Oldman <john.oldman@polehill.co.uk>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

null_blk: Cleanup zoned device initialization

Move all zoned mode related code from null_blk_main.c to
null_blk_zoned.c, avoiding an ugly #ifdef in the process.
Rename null_zone_init() into null_init_zoned_dev(), null_zone_exit()
into null_free_zoned_dev() and add the new function
null_register_zoned_dev() to finalize the zoned dev setup before
add_disk().

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

null_blk: Fix zoned command handling

For write operations issued to a null_blk device with zoned mode
enabled, the state and write pointer position of the zone targeted by
the command should be checked before badblocks and memory backing
are handled as the write may be first failed due to, for instance, a
sector position not aligned with the zone write pointer. This order of
checking for errors reflects more accuratly the behavior of physical
zoned devices.

Furthermore, the write pointer position of the target zone should be
incremented only and only if no errors are reported by badblocks and
memory backing handling.

To fix this, introduce the small helper function null_process_cmd()
which execute null_handle_badblocks() and null_handle_memory_backed()
and use this function in null_zone_write() to correctly handle write
requests to zoned null devices depending on the type and state of the
write target zone. Also call this function in null_handle_zoned() to
process read requests to zoned null devices.

null_process_cmd() is called directly from null_handle_cmd() for
regular null devices, resulting in no functional change for these type
of devices. To have symmetric names, the function null_handle_zoned()
is renamed to null_process_zoned_cmd().

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Merge tag 'arm-soc/for-5.7/devicetree-fixes' of https://github.com/Broadcom/stblinux into arm/fixes

This pull request contains Broadcom ARM-based SoCs Device Tree fixes for
5.7, please pull the following:

- Nicolas provides a fix for 55c7c0621078 ("ARM: dts: bcm283x: Fix vc4's
  firmware bus DMA limitations") which missed adding proper
  #address-cells and #size-cells properties and he also disables the DSI
  node which should have been disabled by default but was not.

* tag 'arm-soc/for-5.7/devicetree-fixes' of https://github.com/Broadcom/stblinux:
  ARM: dts: bcm283x: Disable dsi0 node
  ARM: dts: bcm283x: Add cells encoding format to firmware bus

Link: https://lore.kernel.org/r/20200417171725.1084-1-f.fainelli@gmail.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ALSA: hda: Always use jackpoll helper for jack update after resume

HD-audio codec driver applies a tricky procedure to forcibly perform
the runtime resume by mimicking the usage count even if the device has
been runtime-suspended beforehand.  This was needed to assure to
trigger the jack detection update after the system resume.

And recently we also applied the similar logic to the HD-audio
controller side.  However this seems leading to some inconsistency,
and eventually PCI controller gets screwed up.

This patch is an attempt to fix and clean up those behavior: instead
of the tricky runtime resume procedure, the existing jackpoll work is
scheduled when such a forced codec resume is required.  The jackpoll
work will power up the codec, and this alone should suffice for the
jack status update in usual cases.  If the extra polling is requested
(by checking codec->jackpoll_interval), the manual update is invoked
after that, and the codec is powered down again.

Also, we filter the spurious wake up of the codec from the controller
runtime resume by checking codec->relaxed_resume flag.  If this flag
is set, basically we don't need to wake up explicitly, but it's
supposed to be done via the audio component notifier.

Fixes: c4c8dd6ef807 ("ALSA: hda: Skip controller resume if not needed")
Link: https://lore.kernel.org/r/20200422203744.26299-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

h8300: ignore vmlinux.lds

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

ALSA: hda/realtek - Add new codec supported for ALC245

Enable new codec supported for ALC245.

Signed-off-by: Kailang Yang <kailang@realtek.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/8c0804738b2c42439f59c39c8437817f@realtek.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: usb-audio: Fix usb audio refcnt leak when getting spdif

snd_microii_spdif_default_get() invokes snd_usb_lock_shutdown(), which
increases the refcount of the snd_usb_audio object "chip".

When snd_microii_spdif_default_get() returns, local variable "chip"
becomes invalid, so the refcount should be decreased to keep refcount
balanced.

The reference counting issue happens in several exception handling paths
of snd_microii_spdif_default_get(). When those error scenarios occur
such as usb_ifnum_to_if() returns NULL, the function forgets to decrease
the refcnt increased by snd_usb_lock_shutdown(), causing a refcnt leak.

Fix this issue by jumping to "end" label when those error scenarios
occur.

Fixes: 447d6275f0c2 ("ALSA: usb-audio: Add sanity checks for endpoint accesses")
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/1587617711-13200-1-git-send-email-xiyuyang19@fudan.edu.cn
Signed-off-by: Takashi Iwai <tiwai@suse.de>

tracing: Convert local functions in tracing_map.c to static

Fix the following sparse warning:

kernel/trace/tracing_map.c:286:6: warning: symbol
'tracing_map_array_clear' was not declared. Should it be static?
kernel/trace/tracing_map.c:297:6: warning: symbol
'tracing_map_array_free' was not declared. Should it be static?
kernel/trace/tracing_map.c:319:26: warning: symbol
'tracing_map_array_alloc' was not declared. Should it be static?

Link: http://lkml.kernel.org/r/20200410073312.38855-1-yanaijie@huawei.com
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

tracing: Remove DECLARE_TRACE_NOARGS

This macro was intentionally broken so that the kernel code is not
poluted with such noargs macro used simply as markers. This use case
can be satisfied by using dummy no inline functions. Just remove it.

Link: http://lkml.kernel.org/r/20200413153246.8511-1-nborisov@suse.com
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

ftrace: Fix memory leak caused by not freeing entry in unregister_ftrace_direct()

kmemleak reported the following:

unreferenced object 0xffff90d47127a920 (size 32):
  comm "modprobe", pid 1766, jiffies 4294792031 (age 162.568s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 22 01 00 00 00 00 ad de  ........".......
    00 78 12 a7 ff ff ff ff 00 00 b6 c0 ff ff ff ff  .x..............
  backtrace:
    [<00000000bb79e72e>] register_ftrace_direct+0xcb/0x3a0
    [<00000000295e4f79>] do_one_initcall+0x72/0x340
    [<00000000873ead18>] do_init_module+0x5a/0x220
    [<00000000974d9de5>] load_module+0x2235/0x2550
    [<0000000059c3d6ce>] __do_sys_finit_module+0xc0/0x120
    [<000000005a8611b4>] do_syscall_64+0x60/0x230
    [<00000000a0cdc49e>] entry_SYSCALL_64_after_hwframe+0x49/0xb3

The entry used to save the direct descriptor needs to be freed
when unregistering.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

Documentation: kbuild: fix the section title format

Make it consistent with the other sections.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

um: ensure `make ARCH=um mrproper` removes arch/$(SUBARCH)/include/generated/

In this workflow:

$ make ARCH=um defconfig && make ARCH=um -j8
  [snip]
$ make ARCH=um mrproper
  [snip]
$ make ARCH=um defconfig O=./build_um && make ARCH=um -j8 O=./build_um
  [snip]
  CC      scripts/mod/empty.o
In file included from ../include/linux/types.h:6,
                 from ../include/linux/mod_devicetable.h:12,
                 from ../scripts/mod/devicetable-offsets.c:3:
../include/uapi/linux/types.h:5:10: fatal error: asm/types.h: No such file or directory
    5 | #include <asm/types.h>
      |          ^~~~~~~~~~~~~
compilation terminated.
make[2]: *** [../scripts/Makefile.build:100: scripts/mod/devicetable-offsets.s] Error 1
make[2]: *** Waiting for unfinished jobs....
make[1]: *** [/home/iha/sdb/opensource/lkmp/linux-kselftest.git/Makefile:1140: prepare0] Error 2
make[1]: Leaving directory '/home/iha/sdb/opensource/lkmp/linux-kselftest.git/build_um'
make: *** [Makefile:180: sub-make] Error 2

The cause of the error was because arch/$(SUBARCH)/include/generated files
weren't properly cleaned by `make ARCH=um mrproper`.

Fixes: a788b2ed81ab ("kbuild: check arch/$(SRCARCH)/include/generated before out-of-tree build")
Reported-by: Theodore Ts'o <tytso@mit.edu>
Suggested-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Vitor Massaru Iha <vitor@massaru.org>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Tested-by: Brendan Higgins <brendanhiggins@google.com>
Link: https://groups.google.com/forum/#!msg/kunit-dev/QmA27YEgEgI/hvS1kiz2CwAJ
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

arch: split MODULE_ARCH_VERMAGIC definitions out to <asm/vermagic.h>

As the bug report [1] pointed out, <linux/vermagic.h> must be included
after <linux/module.h>.

I believe we should not impose any include order restriction. We often
sort include directives alphabetically, but it is just coding style
convention. Technically, we can include header files in any order by
making every header self-contained.

Currently, arch-specific MODULE_ARCH_VERMAGIC is defined in
<asm/module.h>, which is not included from <linux/vermagic.h>.

Hence, the straight-forward fix-up would be as follows:

|--- a/include/linux/vermagic.h
|+++ b/include/linux/vermagic.h
|@@ -1,5 +1,6 @@
| /* SPDX-License-Identifier: GPL-2.0 */
| #include <generated/utsrelease.h>
|+#include <linux/module.h>
|
| /* Simply sanity version stamp for modules. */
| #ifdef CONFIG_SMP

This works enough, but for further cleanups, I split MODULE_ARCH_VERMAGIC
definitions into <asm/vermagic.h>.

With this, <linux/module.h> and <linux/vermagic.h> will be orthogonal,
and the location of MODULE_ARCH_VERMAGIC definitions will be consistent.

For arc and ia64, MODULE_PROC_FAMILY is only used for defining
MODULE_ARCH_VERMAGIC. I squashed it.

For hexagon, nds32, and xtensa, I removed <asm/modules.h> entirely
because they contained nothing but MODULE_ARCH_VERMAGIC definition.
Kbuild will automatically generate <asm/modules.h> at build-time,
wrapping <asm-generic/module.h>.

[1] https://lore.kernel.org/lkml/20200411155623.GA22175@zn.tnic

Reported-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Jessica Yu <jeyu@kernel.org>

kbuild: fix DT binding schema rule again to avoid needless rebuilds

Since commit 7a0496056064 ("kbuild: fix DT binding schema rule to detect
command line changes"), this rule is every time re-run even if you change
nothing.

cmd_dtc takes one additional parameter to pass to the -O option of dtc.

We need to pass 'yaml' to if_changed_rule. Otherwise, cmd-check invoked
from if_changed_rule is false positive.

Fixes: 7a0496056064 ("kbuild: fix DT binding schema rule to detect command line changes")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

tracing: Fix memory leaks in trace_events_hist.c

kmemleak report 1:
    [<9092c50b>] kmem_cache_alloc_trace+0x138/0x270
    [<05a2c9ed>] create_field_var+0xcf/0x180
    [<528a2d68>] action_create+0xe2/0xc80
    [<63f50b61>] event_hist_trigger_func+0x15b5/0x1920
    [<28ea5d3d>] trigger_process_regex+0x7b/0xc0
    [<3138e86f>] event_trigger_write+0x4d/0xb0
    [<ffd66c19>] __vfs_write+0x30/0x200
    [<4f424a0d>] vfs_write+0x96/0x1b0
    [<da59a290>] ksys_write+0x53/0xc0
    [<3717101a>] __ia32_sys_write+0x15/0x20
    [<c5f23497>] do_fast_syscall_32+0x70/0x250
    [<46e2629c>] entry_SYSENTER_32+0xaf/0x102

This is because save_vars[] of struct hist_trigger_data are
not destroyed

kmemleak report 2:
    [<9092c50b>] kmem_cache_alloc_trace+0x138/0x270
    [<6e5e97c5>] create_var+0x3c/0x110
    [<de82f1b9>] create_field_var+0xaf/0x180
    [<528a2d68>] action_create+0xe2/0xc80
    [<63f50b61>] event_hist_trigger_func+0x15b5/0x1920
    [<28ea5d3d>] trigger_process_regex+0x7b/0xc0
    [<3138e86f>] event_trigger_write+0x4d/0xb0
    [<ffd66c19>] __vfs_write+0x30/0x200
    [<4f424a0d>] vfs_write+0x96/0x1b0
    [<da59a290>] ksys_write+0x53/0xc0
    [<3717101a>] __ia32_sys_write+0x15/0x20
    [<c5f23497>] do_fast_syscall_32+0x70/0x250
    [<46e2629c>] entry_SYSENTER_32+0xaf/0x102

struct hist_field allocated through create_var() do not initialize
"ref" field to 1. The code in __destroy_hist_field() does not destroy
object if "ref" is initialized to zero, the condition
if (--hist_field->ref > 1) always passes since unsigned int wraps.

kmemleak report 3:
    [<f8666fcc>] __kmalloc_track_caller+0x139/0x2b0
    [<bb7f80a5>] kstrdup+0x27/0x50
    [<39d70006>] init_var_ref+0x58/0xd0
    [<8ca76370>] create_var_ref+0x89/0xe0
    [<f045fc39>] action_create+0x38f/0xc80
    [<7c146821>] event_hist_trigger_func+0x15b5/0x1920
    [<07de3f61>] trigger_process_regex+0x7b/0xc0
    [<e87daf8f>] event_trigger_write+0x4d/0xb0
    [<19bf1512>] __vfs_write+0x30/0x200
    [<64ce4d27>] vfs_write+0x96/0x1b0
    [<a6f34170>] ksys_write+0x53/0xc0
    [<7d4230cd>] __ia32_sys_write+0x15/0x20
    [<8eadca00>] do_fast_syscall_32+0x70/0x250
    [<235cf985>] entry_SYSENTER_32+0xaf/0x102

hist_fields (system & event_name) are not freed

Link: http://lkml.kernel.org/r/20200422061503.GA5151@cosmos
Signed-off-by: Vamshi K Sthambamkadi <vamshi.k.sthambamkadi@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

Merge tag 'linux-kselftest-5.7-rc3' of git://git./linux/kernel/git/shuah/linux-kselftest

Pull kselftest fixes from Shuah Khan:
"This consists of fixes to runner scripts and individual test run-time
  bugs. Includes fixes to tpm2 and memfd test run-time regressions"

* tag 'linux-kselftest-5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  selftests/ipc: Fix test failure seen after initial test run
  Revert "Kernel selftests: tpm2: check for tpm support"
  selftests/ftrace: Add CONFIG_SAMPLE_FTRACE_DIRECT=m kconfig
  selftests/seccomp: allow clock_nanosleep instead of nanosleep
  kselftest/runner: allow to properly deliver signals to tests
  selftests/harness: fix spelling mistake "SIGARLM" -> "SIGALRM"
  selftests: Fix memfd test run-time regression
  selftests: vm: Fix 64-bit test builds for powerpc64le
  selftests: vm: Do not override definition of ARCH

scripts/config: allow colons in option strings for sed

Sed broke on some strings as it used colon as a separator.
I made it more robust by using \001, which is legit POSIX AFAIK.

E.g. ./config --set-str CONFIG_USBNET_DEVADDR "de:ad:be:ef:00:01"
failed with: sed: -e expression #1, char 55: unknown option to `s'

Signed-off-by: Jeremie Francois (on alpha) <jeremie.francois@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

MAINTAINERS: Add Rob Herring and remove Andy Murray as PCI reviewers

Andy Murray decided to step down as PCI controller reviewer and Rob Herring
is willing to help review PCI controller patches.

Update the respective MAINTAINERS entries to reflect this change.

Link: https://lore.kernel.org/r/20200422150336.10528-1-lorenzo.pieralisi@arm.com
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rob Herring <robh@kernel.org>
Cc: Andrew Murray <amurray@thegoodpenguin.co.uk>

ALSA: usb-audio: Add connector notifier delegation

It turned out that ALC1220-VB USB-audio device gives the interrupt
event to some PCM terminals while those don't allow the connector
state request but only the actual I/O terminals return the request.
The recent commit 7dc3c5a0172e ("ALSA: usb-audio: Don't create jack
controls for PCM terminals") excluded those phantom terminals, so
those events are ignored, too.

My first thought was that this could be easily deduced from the
associated terminals, but some of them have even no associate terminal
ID, hence it's not too trivial to figure out.

Since the number of such terminals are small and limited, this patch
implements another quirk table for the simple mapping of the
connectors. It's not really scalable, but let's hope that there will
be not many such funky devices in future.

Fixes: 7dc3c5a0172e ("ALSA: usb-audio: Don't create jack controls for PCM terminals")
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=206873
Link: https://lore.kernel.org/r/20200422113320.26664-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

exfat: truncate atimes to 2s granularity

The timestamp for access_time has double seconds granularity(There is no
10msIncrement field for access_time unlike create/modify_time).
exfat's atimes are restricted to only 2s granularity so after
we set an atime, round it down to the nearest 2s and set the
sub-second component of the timestamp to 0.

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>

exfat: properly set s_time_gran

The s_time_gran superblock field indicates the on-disk nanosecond
granularity of timestamps, and for exfat that seems to be 10ms, so
set s_time_gran to 10000000ns. Without this, in-memory timestamps
change when they get re-read from disk.

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>

exfat: remove 'bps' mount-option

remount fails because exfat_show_options() returns unsupported
option 'bps'.
> # mount -o ro,remount
> exfat: Unknown parameter 'bps'

To fix the problem, just remove 'bps' option from exfat_show_options().

Signed-off-by: Tetsuhiro Kohada <Kohada.Tetsuhiro@dc.MitsubishiElectric.co.jp>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>

exfat: Unify access to the boot sector

Unify access to boot sector via 'sbi->pbr_bh'.
This fixes vol_flags inconsistency at read failed in fs_set_vol_flags(),
and buffer_head leak in __exfat_fill_super().

Signed-off-by: Tetsuhiro Kohada <Kohada.Tetsuhiro@dc.MitsubishiElectric.co.jp>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>

exfat: add missing MODULE_ALIAS_FS()

This adds the necessary MODULE_ALIAS_FS() to exfat so the module gets
automatically loaded when an exfat filesystem is mounted.

Signed-off-by: Thomas Backlund <tmb@mageia.org>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>

exfat: Fix discard support

Discard support was always unconditionally disabled. Now it is disabled
only in the case when blk_queue_discard() returns false.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>

Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:
"15 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  tools/vm: fix cross-compile build
  coredump: fix null pointer dereference on coredump
  mm: shmem: disable interrupt when acquiring info->lock in userfaultfd_copy path
  shmem: fix possible deadlocks on shmlock_user_lock
  vmalloc: fix remap_vmalloc_range() bounds checks
  mm/shmem: fix build without THP
  mm/ksm: fix NULL pointer dereference when KSM zero page is enabled
  tools/build: tweak unused value workaround
  checkpatch: fix a typo in the regex for $allocFunctions
  mm, gup: return EINTR when gup is interrupted by fatal signals
  mm/hugetlb: fix a addressing exception caused by huge_pte_offset
  MAINTAINERS: add an entry for kfifo
  mm/userfaultfd: disable userfaultfd-wp on x86_32
  slub: avoid redzone when choosing freepointer location
  sh: fix build error in mm/init.c

Merge tag 'for-linus' of git://git./virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:
"Bugfixes, and a few cleanups to the newly-introduced assembly language
  vmentry code for AMD"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: PPC: Book3S HV: Handle non-present PTEs in page fault functions
  kvm: Disable objtool frame pointer checking for vmenter.S
  MAINTAINERS: add a reviewer for KVM/s390
  KVM: s390: Fix PV check in deliverable_irqs()
  kvm: Handle reads of SandyBridge RAPL PMU MSRs rather than injecting #GP
  KVM: Remove CREATE_IRQCHIP/SET_PIT2 race
  KVM: SVM: Fix __svm_vcpu_run declaration.
  KVM: SVM: Do not setup frame pointer in __svm_vcpu_run
  KVM: SVM: Fix build error due to missing release_pages() include
  KVM: SVM: Do not mark svm_vcpu_run with STACK_FRAME_NON_STANDARD
  kvm: nVMX: match comment with return type for nested_vmx_exit_reflected
  kvm: nVMX: reflect MTF VM-exits if injected by L1
  KVM: s390: Return last valid slot if approx index is out-of-bounds
  KVM: Check validity of resolved slot when searching memslots
  KVM: VMX: Enable machine check support for 32bit targets
  KVM: SVM: move more vmentry code to assembly
  KVM: SVM: fix compilation with modular PSP and non-modular KVM

Merge tag 'asoc-fix-v5.7-rc2' of https://git./linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v5.7

Quite a lot of fixes here, a lot of driver specific ones but the biggest
one is the revert of changes to the startup and shutdown sequence for
DAIs that went in during the merge window - they broke some older x86
platforms and attempts to fix them didn't succeed so it's safer to just
roll them back and try to make sure those platforms are handled properly
in any future attempt.

The rockchip S/PDIF DT stuff was IIRC for validation issues.

ALSA: usb-audio: Apply async workaround for Scarlett 2i4 2nd gen

Due to rounding error driver sometimes incorrectly calculate next packet
size, which results in audible clicks on devices with synchronous playback
endpoints. For example on a high speed bus and a sample rate 44.1 kHz it
loses one sample every ~40.9 seconds. Fortunately playback interface on
Scarlett 2i4 2nd gen has a working explicit feedback endpoint, so we can
switch playback data endpoint to asynchronous mode as a workaround.

Signed-off-by: Alexander Tsoy <alexander@tsoy.me>
Link: https://lore.kernel.org/r/20200421190908.462860-1-alexander@tsoy.me
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Merge tag 'for_linus' of git://git./linux/kernel/git/mst/vhost

Pull virtio fixes and cleanups from Michael Tsirkin:

- Some bug fixes

- Cleanup a couple of issues that surfaced meanwhile

- Disable vhost on ARM with OABI for now - to be fixed fully later in
   the cycle or in the next release.

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (24 commits)
  vhost: disable for OABI
  virtio: drop vringh.h dependency
  virtio_blk: add a missing include
  virtio-balloon: Avoid using the word 'report' when referring to free page hinting
  virtio-balloon: make virtballoon_free_page_report() static
  vdpa: fix comment of vdpa_register_device()
  vdpa: make vhost, virtio depend on menu
  vdpa: allow a 32 bit vq alignment
  drm/virtio: fix up for include file changes
  remoteproc: pull in slab.h
  rpmsg: pull in slab.h
  virtio_input: pull in slab.h
  remoteproc: pull in slab.h
  virtio-rng: pull in slab.h
  virtgpu: pull in uaccess.h
  tools/virtio: make asm/barrier.h self contained
  tools/virtio: define aligned attribute
  virtio/test: fix up after IOTLB changes
  vhost: Create accessors for virtqueues private_data
  vdpasim: Return status in vdpasim_get_status
  ...

Merge tag 'tpmdd-next-20200421' of git://git.infradead.org/users/jjs/linux-tpmdd

Pull tpm fixes from Jarkko Sakkinen:
"A few bug fixes"

* tag 'tpmdd-next-20200421' of git://git.infradead.org/users/jjs/linux-tpmdd:
  tpm/tpm_tis: Free IRQ if probing fails
  tpm: fix wrong return value in tpm_pcr_extend
  tpm: ibmvtpm: retry on H_CLOSED in tpm_ibmvtpm_send()
  tpm: Export tpm2_get_cc_attrs_tbl for ibmvtpm driver as module

Merge tag 'clang-format-for-linus-v5.7-rc3' of git://github.com/ojeda/linux

Pull clang-format fixlets from Miguel Ojeda:
"Two trivial clang-format changes:

   - Don't indent C++ namespaces (Ian Rogers)

   - The usual clang-format macro list update (Miguel Ojeda)"

* tag 'clang-format-for-linus-v5.7-rc3' of git://github.com/ojeda/linux:
  clang-format: Update with the latest for_each macro list
  clang-format: don't indent namespaces

tools/vm: fix cross-compile build

Commit 7ed1c1901fe5 ("tools: fix cross-compile var clobbering") moved
the setup of the CC variable to tools/scripts/Makefile.include to make
the behavior consistent across all the tools Makefiles.

As the vm tools missed the include we end up with the wrong CC in a
cross-compiling evironment.

Fixes: 7ed1c1901fe5 (tools: fix cross-compile var clobbering)
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Martin Kelly <martin@martingkelly.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200416104748.25243-1-l.stach@pengutronix.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

coredump: fix null pointer dereference on coredump

If the core_pattern is set to "|" and any process segfaults then we get
a null pointer derefernce while trying to coredump. The call stack shows:

    RIP: do_coredump+0x628/0x11c0

When the core_pattern has only "|" there is no use of trying the
coredump and we can check that while formating the corename and exit
with an error.

After this change I get:

    format_corename failed
    Aborting core

Fixes: 315c69261dd3 ("coredump: split pipe command whitespace before expanding template")
Reported-by: Matthew Ruffell <matthew.ruffell@canonical.com>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Wise <pabs3@bonedaddy.net>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200416194612.21418-1-sudipm.mukherjee@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: shmem: disable interrupt when acquiring info->lock in userfaultfd_copy path

Syzbot reported the below lockdep splat:

    WARNING: possible irq lock inversion dependency detected
    5.6.0-rc7-syzkaller #0 Not tainted
    --------------------------------------------------------
    syz-executor.0/10317 just changed the state of lock:
    ffff888021d16568 (&(&info->lock)->rlock){+.+.}, at: spin_lock include/linux/spinlock.h:338 [inline]
    ffff888021d16568 (&(&info->lock)->rlock){+.+.}, at: shmem_mfill_atomic_pte+0x1012/0x21c0 mm/shmem.c:2407
    but this lock was taken by another, SOFTIRQ-safe lock in the past:
     (&(&xa->xa_lock)->rlock#5){..-.}

    and interrupts could create inverse lock ordering between them.

    other info that might help us debug this:
     Possible interrupt unsafe locking scenario:

           CPU0                    CPU1
           ----                    ----
      lock(&(&info->lock)->rlock);
                                   local_irq_disable();
                                   lock(&(&xa->xa_lock)->rlock#5);
                                   lock(&(&info->lock)->rlock);
      <Interrupt>
        lock(&(&xa->xa_lock)->rlock#5);

     *** DEADLOCK ***

The full report is quite lengthy, please see:

  https://lore.kernel.org/linux-mm/alpine.LSU.2.11.2004152007370.13597@eggly.anvils/T/#m813b412c5f78e25ca8c6c7734886ed4de43f241d

It is because CPU 0 held info->lock with IRQ enabled in userfaultfd_copy
path, then CPU 1 is splitting a THP which held xa_lock and info->lock in
IRQ disabled context at the same time.  If softirq comes in to acquire
xa_lock, the deadlock would be triggered.

The fix is to acquire/release info->lock with *_irq version instead of
plain spin_{lock,unlock} to make it softirq safe.

Fixes: 4c27fe4c4c84 ("userfaultfd: shmem: add shmem_mcopy_atomic_pte for userfaultfd support")
Reported-by: syzbot+e27980339d305f2dbfd9@syzkaller.appspotmail.com
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: syzbot+e27980339d305f2dbfd9@syzkaller.appspotmail.com
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Link: http://lkml.kernel.org/r/1587061357-122619-1-git-send-email-yang.shi@linux.alibaba.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

shmem: fix possible deadlocks on shmlock_user_lock

Recent commit 71725ed10c40 ("mm: huge tmpfs: try to split_huge_page()
when punching hole") has allowed syzkaller to probe deeper, uncovering a
long-standing lockdep issue between the irq-unsafe shmlock_user_lock,
the irq-safe xa_lock on mapping->i_pages, and shmem inode's info->lock
which nests inside xa_lock (or tree_lock) since 4.8's shmem_uncharge().

user_shm_lock(), servicing SysV shmctl(SHM_LOCK), wants
shmlock_user_lock while its caller shmem_lock() holds info->lock with
interrupts disabled; but hugetlbfs_file_setup() calls user_shm_lock()
with interrupts enabled, and might be interrupted by a writeback endio
wanting xa_lock on i_pages.

This may not risk an actual deadlock, since shmem inodes do not take
part in writeback accounting, but there are several easy ways to avoid
it.

Requiring interrupts disabled for shmlock_user_lock would be easy, but
it's a high-level global lock for which that seems inappropriate.
Instead, recall that the use of info->lock to guard info->flags in
shmem_lock() dates from pre-3.1 days, when races with SHMEM_PAGEIN and
SHMEM_TRUNCATE could occur: nowadays it serves no purpose, the only flag
added or removed is VM_LOCKED itself, and calls to shmem_lock() an inode
are already serialized by the caller.

Take info->lock out of the chain and the possibility of deadlock or
lockdep warning goes away.

Fixes: 4595ef88d136 ("shmem: make shmem_inode_info::lock irq-safe")
Reported-by: syzbot+c8a8197c8852f566b9d9@syzkaller.appspotmail.com
Reported-by: syzbot+40b71e145e73f78f81ad@syzkaller.appspotmail.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2004161707410.16322@eggly.anvils
Link: https://lore.kernel.org/lkml/000000000000e5838c05a3152f53@google.com/
Link: https://lore.kernel.org/lkml/0000000000003712b305a331d3b1@google.com/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

vmalloc: fix remap_vmalloc_range() bounds checks

remap_vmalloc_range() has had various issues with the bounds checks it
promises to perform ("This function checks that addr is a valid
vmalloc'ed area, and that it is big enough to cover the vma") over time,
e.g.:

- not detecting pgoff<<PAGE_SHIFT overflow

- not detecting (pgoff<<PAGE_SHIFT)+usize overflow

- not checking whether addr and addr+(pgoff<<PAGE_SHIFT) are the same
vmalloc allocation

- comparing a potentially wildly out-of-bounds pointer with the end of
the vmalloc region

In particular, since commit fc9702273e2e ("bpf: Add mmap() support for
BPF_MAP_TYPE_ARRAY"), unprivileged users can cause kernel null pointer
dereferences by calling mmap() on a BPF map with a size that is bigger
than the distance from the start of the BPF map to the end of the
address space.

This could theoretically be used as a kernel ASLR bypass, by using
whether mmap() with a given offset oopses or returns an error code to
perform a binary search over the possible address range.

To allow remap_vmalloc_range_partial() to verify that addr and
addr+(pgoff<<PAGE_SHIFT) are in the same vmalloc region, pass the offset
to remap_vmalloc_range_partial() instead of adding it to the pointer in
remap_vmalloc_range().

In remap_vmalloc_range_partial(), fix the check against
get_vm_area_size() by using size comparisons instead of pointer
comparisons, and add checks for pgoff.

Fixes: 833423143c3a ("[PATCH] mm: introduce remap_vmalloc_range()")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@vger.kernel.org
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@chromium.org>
Link: http://lkml.kernel.org/r/20200415222312.236431-1-jannh@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/shmem: fix build without THP

Some optimizers don't notice that shmem_punch_compound() is always true
(PageTransCompound() being false) without CONFIG_TRANSPARENT_HUGEPAGE==y.

Use IS_ENABLED to help them to avoid the BUILD_BUG inside HPAGE_PMD_NR.

Fixes: 71725ed10c40 ("mm: huge tmpfs: try to split_huge_page() when punching hole")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2004142339170.10035@eggly.anvils
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/ksm: fix NULL pointer dereference when KSM zero page is enabled

find_mergeable_vma() can return NULL.  In this case, it leads to a crash
when we access vm_mm(its offset is 0x40) later in write_protect_page.
And this case did happen on our server.  The following call trace is
captured in kernel 4.19 with the following patch applied and KSM zero
page enabled on our server.

  commit e86c59b1b12d ("mm/ksm: improve deduplication of zero pages with colouring")

So add a vma check to fix it.

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000040
  Oops: 0000 [#1] SMP NOPTI
  CPU: 9 PID: 510 Comm: ksmd Kdump: loaded Tainted: G OE 4.19.36.bsk.9-amd64 #4.19.36.bsk.9
  RIP: try_to_merge_one_page+0xc7/0x760
  Code: 24 58 65 48 33 34 25 28 00 00 00 89 e8 0f 85 a3 06 00 00 48 83 c4
        60 5b 5d 41 5c 41 5d 41 5e 41 5f c3 48 8b 46 08 a8 01 75 b8 <49>
        8b 44 24 40 4c 8d 7c 24 20 b9 07 00 00 00 4c 89 e6 4c 89 ff 48
  RSP: 0018:ffffadbdd9fffdb0 EFLAGS: 00010246
  RAX: ffffda83ffd4be08 RBX: ffffda83ffd4be40 RCX: 0000002c6e800000
  RDX: 0000000000000000 RSI: ffffda83ffd4be40 RDI: 0000000000000000
  RBP: ffffa11939f02ec0 R08: 0000000094e1a447 R09: 00000000abe76577
  R10: 0000000000000962 R11: 0000000000004e6a R12: 0000000000000000
  R13: ffffda83b1e06380 R14: ffffa18f31f072c0 R15: ffffda83ffd4be40
  FS: 0000000000000000(0000) GS:ffffa0da43b80000(0000) knlGS:0000000000000000
  CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000040 CR3: 0000002c77c0a003 CR4: 00000000007626e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  PKRU: 55555554
  Call Trace:
    ksm_scan_thread+0x115e/0x1960
    kthread+0xf5/0x130
    ret_from_fork+0x1f/0x30

[songmuchun@bytedance.com: if the vma is out of date, just exit]
Link: http://lkml.kernel.org/r/20200416025034.29780-1-songmuchun@bytedance.com
[akpm@linux-foundation.org: add the conventional braces, replace /** with /*]
Fixes: e86c59b1b12d ("mm/ksm: improve deduplication of zero pages with colouring")
Co-developed-by: Xiongchun Duan <duanxiongchun@bytedance.com>
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Cc: Markus Elfring <Markus.Elfring@web.de>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200416025034.29780-1-songmuchun@bytedance.com
Link: http://lkml.kernel.org/r/20200414132905.83819-1-songmuchun@bytedance.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

tools/build: tweak unused value workaround

Clang has -Wself-assign enabled by default under -Wall, which always
gets -Werror'ed on this file, causing sync-compare-and-swap to be
disabled by default.

The generally-accepted way to spell "this value is intentionally
unused," is casting it to `void`. This is accepted by both GCC and
Clang with -Wall enabled: https://godbolt.org/z/qqZ9r3

Signed-off-by: George Burgess IV <gbiv@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Link: http://lkml.kernel.org/r/20200414195638.156123-1-gbiv@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: fix a typo in the regex for $allocFunctions

Here, we look for function such as 'netdev_alloc_skb_ip_align', so a '_'
is missing in the regex.

To make sure:
grep -r --include=*.c skbip_a * | wc ==> 0 results
grep -r --include=*.c skb_ip_a * | wc ==> 112 results

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Joe Perches <joe@perches.com>
Link: http://lkml.kernel.org/r/20200407190029.892-1-christophe.jaillet@wanadoo.fr
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm, gup: return EINTR when gup is interrupted by fatal signals

EINTR is the usual error code which other killable interfaces return.
This is the case for the other fatal_signal_pending break out from the
same function. Make the code consistent.

ERESTARTSYS is also quite confusing because the signal is fatal and so
no restart will happen before returning to the userspace.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Link: http://lkml.kernel.org/r/20200409071133.31734-1-mhocko@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/hugetlb: fix a addressing exception caused by huge_pte_offset

Our machine encountered a panic(addressing exception) after run for a
long time and the calltrace is:

    RIP: hugetlb_fault+0x307/0xbe0
    RSP: 0018:ffff9567fc27f808  EFLAGS: 00010286
    RAX: e800c03ff1258d48 RBX: ffffd3bb003b69c0 RCX: e800c03ff1258d48
    RDX: 17ff3fc00eda72b7 RSI: 00003ffffffff000 RDI: e800c03ff1258d48
    RBP: ffff9567fc27f8c8 R08: e800c03ff1258d48 R09: 0000000000000080
    R10: ffffaba0704c22a8 R11: 0000000000000001 R12: ffff95c87b4b60d8
    R13: 00005fff00000000 R14: 0000000000000000 R15: ffff9567face8074
    FS:  00007fe2d9ffb700(0000) GS:ffff956900e40000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: ffffd3bb003b69c0 CR3: 000000be67374000 CR4: 00000000003627e0
    DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
    DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
    Call Trace:
      follow_hugetlb_page+0x175/0x540
      __get_user_pages+0x2a0/0x7e0
      __get_user_pages_unlocked+0x15d/0x210
      __gfn_to_pfn_memslot+0x3c5/0x460 [kvm]
      try_async_pf+0x6e/0x2a0 [kvm]
      tdp_page_fault+0x151/0x2d0 [kvm]
     ...
      kvm_arch_vcpu_ioctl_run+0x330/0x490 [kvm]
      kvm_vcpu_ioctl+0x309/0x6d0 [kvm]
      do_vfs_ioctl+0x3f0/0x540
      SyS_ioctl+0xa1/0xc0
      system_call_fastpath+0x22/0x27

For 1G hugepages, huge_pte_offset() wants to return NULL or pudp, but it
may return a wrong 'pmdp' if there is a race.  Please look at the
following code snippet:

    ...
    pud = pud_offset(p4d, addr);
    if (sz != PUD_SIZE && pud_none(*pud))
        return NULL;
    /* hugepage or swap? */
    if (pud_huge(*pud) || !pud_present(*pud))
        return (pte_t *)pud;

    pmd = pmd_offset(pud, addr);
    if (sz != PMD_SIZE && pmd_none(*pmd))
        return NULL;
    /* hugepage or swap? */
    if (pmd_huge(*pmd) || !pmd_present(*pmd))
        return (pte_t *)pmd;
    ...

The following sequence would trigger this bug:

- CPU0: sz = PUD_SIZE and *pud = 0 , continue
- CPU0: "pud_huge(*pud)" is false
- CPU1: calling hugetlb_no_page and set *pud to xxxx8e7(PRESENT)
- CPU0: "!pud_present(*pud)" is false, continue
- CPU0: pmd = pmd_offset(pud, addr) and maybe return a wrong pmdp

However, we want CPU0 to return NULL or pudp in this case.

We must make sure there is exactly one dereference of pud and pmd.

Signed-off-by: Longpeng <longpeng2@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200413010342.771-1-longpeng2@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: add an entry for kfifo

Kfifo has been written by Stefani Seibold and she's implicitly expected
to Ack any changes to it. She's not however officially listed as kfifo
maintainer which leads to delays in patch review. This patch proposes
to add an explitic entry for kfifo to MAINTAINERS file.

[akpm@linux-foundation.org: alphasort F: entries, per Joe]
[akpm@linux-foundation.org: remove colon, per Bartosz]
Link: http://lkml.kernel.org/r/20200124174533.21815-1-brgl@bgdev.pl
Link: http://lkml.kernel.org/r/20200413104250.26683-1-brgl@bgdev.pl
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Stefani Seibold <stefani@seibold.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/userfaultfd: disable userfaultfd-wp on x86_32

Userfaultfd-wp is not yet working on 32bit hosts, but it's accidentally
enabled previously. Disable it.

Fixes: 5a281062af1d ("userfaultfd: wp: add WP pagetable tracking to x86")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Link: http://lkml.kernel.org/r/20200413141608.109211-1-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

slub: avoid redzone when choosing freepointer location

Marco Elver reported system crashes when booting with "slub_debug=Z".

The freepointer location (s->offset) was not taking into account that
the "inuse" size that includes the redzone area should not be used by
the freelist pointer. Change the calculation to save the area of the
object that an inline freepointer may be written into.

Fixes: 3202fa62fb43 ("slub: relocate freelist pointer to middle of object")
Reported-by: Marco Elver <elver@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Marco Elver <elver@google.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>
Link: http://lkml.kernel.org/r/202004151054.BD695840@keescook
Link: https://lore.kernel.org/linux-mm/20200415164726.GA234932@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

sh: fix build error in mm/init.c

The closing parenthesis is missing.

Fixes: bfeb022f8fe4 ("mm/memory_hotplug: add pgprot_t to mhp_params")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Link: http://lkml.kernel.org/r/20200413014743.16353-1-masahiroy@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

block: remove unused header

Dax related code already removed from this file.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jianpeng Ma <jianpeng.ma@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-iocost: Fix error on iocost_ioc_vrate_adj

Systemtap 4.2 is unable to correctly interpret the "u32 (*missed_ppm)[2]"
argument of the iocost_ioc_vrate_adj trace entry defined in
include/trace/events/iocost.h leading to the following error:

  /tmp/stapAcz0G0/stap_c89c58b83cea1724e26395efa9ed4939_6321_aux_6.c:78:8:
  error: expected ‘;’, ‘,’ or ‘)’ before ‘*’ token
   , u32[]* __tracepoint_arg_missed_ppm

That argument type is indeed rather complex and hard to read. Looking
at block/blk-iocost.c. It is just a 2-entry u32 array. By simplifying
the argument to a simple "u32 *missed_ppm" and adjusting the trace
entry accordingly, the compilation error was gone.

Fixes: 7caa47151ab2 ("blkcg: implement blk-iocost")
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

signal: Avoid corrupting si_pid and si_uid in do_notify_parent

Christof Meerwald <cmeerw@cmeerw.org> writes:
> Hi,
>
> this is probably related to commit
> 7a0cf094944e2540758b7f957eb6846d5126f535 (signal: Correct namespace
> fixups of si_pid and si_uid).
>
> With a 5.6.5 kernel I am seeing SIGCHLD signals that don't include a
> properly set si_pid field - this seems to happen for multi-threaded
> child processes.
>
> A simple test program (based on the sample from the signalfd man page):
>
> #include <sys/signalfd.h>
> #include <signal.h>
> #include <unistd.h>
> #include <spawn.h>
> #include <stdlib.h>
> #include <stdio.h>
>
> #define handle_error(msg) \
>     do { perror(msg); exit(EXIT_FAILURE); } while (0)
>
> int main(int argc, char *argv[])
> {
>   sigset_t mask;
>   int sfd;
>   struct signalfd_siginfo fdsi;
>   ssize_t s;
>
>   sigemptyset(&mask);
>   sigaddset(&mask, SIGCHLD);
>
>   if (sigprocmask(SIG_BLOCK, &mask, NULL) == -1)
>     handle_error("sigprocmask");
>
>   pid_t chldpid;
>   char *chldargv[] = { "./sfdclient", NULL };
>   posix_spawn(&chldpid, "./sfdclient", NULL, NULL, chldargv, NULL);
>
>   sfd = signalfd(-1, &mask, 0);
>   if (sfd == -1)
>     handle_error("signalfd");
>
>   for (;;) {
>     s = read(sfd, &fdsi, sizeof(struct signalfd_siginfo));
>     if (s != sizeof(struct signalfd_siginfo))
>       handle_error("read");
>
>     if (fdsi.ssi_signo == SIGCHLD) {
>       printf("Got SIGCHLD %d %d %d %d\n",
>           fdsi.ssi_status, fdsi.ssi_code,
>           fdsi.ssi_uid, fdsi.ssi_pid);
>       return 0;
>     } else {
>       printf("Read unexpected signal\n");
>     }
>   }
> }
>
>
> and a multi-threaded client to test with:
>
> #include <unistd.h>
> #include <pthread.h>
>
> void *f(void *arg)
> {
>   sleep(100);
> }
>
> int main()
> {
>   pthread_t t[8];
>
>   for (int i = 0; i != 8; ++i)
>   {
>     pthread_create(&t[i], NULL, f, NULL);
>   }
> }
>
> I tried to do a bit of debugging and what seems to be happening is
> that
>
>   /* From an ancestor pid namespace? */
>   if (!task_pid_nr_ns(current, task_active_pid_ns(t))) {
>
> fails inside task_pid_nr_ns because the check for "pid_alive" fails.
>
> This code seems to be called from do_notify_parent and there we
> actually have "tsk != current" (I am assuming both are threads of the
> current process?)

I instrumented the code with a warning and received the following backtrace:
> WARNING: CPU: 0 PID: 777 at kernel/pid.c:501 __task_pid_nr_ns.cold.6+0xc/0x15
> Modules linked in:
> CPU: 0 PID: 777 Comm: sfdclient Not tainted 5.7.0-rc1userns+ #2924
> Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
> RIP: 0010:__task_pid_nr_ns.cold.6+0xc/0x15
> Code: ff 66 90 48 83 ec 08 89 7c 24 04 48 8d 7e 08 48 8d 74 24 04 e8 9a b6 44 00 48 83 c4 08 c3 48 c7 c7 59 9f ac 82 e8 c2 c4 04 00 <0f> 0b e9 3fd
> RSP: 0018:ffffc9000042fbf8 EFLAGS: 00010046
> RAX: 000000000000000c RBX: 0000000000000000 RCX: ffffc9000042faf4
> RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff81193d29
> RBP: ffffc9000042fc18 R08: 0000000000000000 R09: 0000000000000001
> R10: 000000100f938416 R11: 0000000000000309 R12: ffff8880b941c140
> R13: 0000000000000000 R14: 0000000000000000 R15: ffff8880b941c140
> FS:  0000000000000000(0000) GS:ffff8880bca00000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007f2e8c0a32e0 CR3: 0000000002e10000 CR4: 00000000000006f0
> Call Trace:
>  send_signal+0x1c8/0x310
>  do_notify_parent+0x50f/0x550
>  release_task.part.21+0x4fd/0x620
>  do_exit+0x6f6/0xaf0
>  do_group_exit+0x42/0xb0
>  get_signal+0x13b/0xbb0
>  do_signal+0x2b/0x670
>  ? __audit_syscall_exit+0x24d/0x2b0
>  ? rcu_read_lock_sched_held+0x4d/0x60
>  ? kfree+0x24c/0x2b0
>  do_syscall_64+0x176/0x640
>  ? trace_hardirqs_off_thunk+0x1a/0x1c
>  entry_SYSCALL_64_after_hwframe+0x49/0xb3

The immediate problem is as Christof noticed that "pid_alive(current) == false".
This happens because do_notify_parent is called from the last thread to exit
in a process after that thread has been reaped.

The bigger issue is that do_notify_parent can be called from any
process that manages to wait on a thread of a multi-threaded process
from wait_task_zombie.  So any logic based upon current for
do_notify_parent is just nonsense, as current can be pretty much
anything.

So change do_notify_parent to call __send_signal directly.

Inspecting the code it appears this problem has existed since the pid
namespace support started handling this case in 2.6.30.  This fix only
backports to 7a0cf094944e ("signal: Correct namespace fixups of si_pid and si_uid")
where the problem logic was moved out of __send_signal and into send_signal.

Cc: stable@vger.kernel.org
Fixes: 6588c1e3ff01 ("signals: SI_USER: Masquerade si_pid when crossing pid ns boundary")
Ref: 921cf9f63089 ("signals: protect cinit from unblocked SIG_DFL signals")
Link: https://lore.kernel.org/lkml/20200419201336.GI22017@edge.cmeerw.net/
Reported-by: Christof Meerwald <cmeerw@cmeerw.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

arm64: sync kernel APIAKey when installing

A direct write to a APxxKey_EL1 register requires a context
synchronization event to ensure that indirect reads made by subsequent
instructions (e.g. AUTIASP, PACIASP) observe the new value.

When we initialize the boot task's APIAKey in boot_init_stack_canary()
via ptrauth_keys_switch_kernel() we miss the necessary ISB, and so there
is a window where instructions are not guaranteed to use the new APIAKey
value. This has been observed to result in boot-time crashes where
PACIASP and AUTIASP within a function used a mixture of the old and new
key values.

Fix this by having ptrauth_keys_switch_kernel() synchronize the new key
value with an ISB. At the same time, __ptrauth_key_install() is renamed
to __ptrauth_key_install_nosync() so that it is obvious that this
performs no synchronization itself.

Fixes: 28321582334c261c ("arm64: initialize ptrauth keys for kernel booting task")
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reported-by: Will Deacon <will@kernel.org>
Cc: Amit Daniel Kachhap <amit.kachhap@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Will Deacon <will@kernel.org>

ASoC: wm8960: Fix wrong clock after suspend & resume

After suspend & resume, wm8960_hw_params may be called when
bias_level is not SND_SOC_BIAS_ON, then wm8960_configure_clocking
is not called. But if sample rate is changed at that time, then
the output clock rate will be not correct.

So judgement of bias_level is SND_SOC_BIAS_ON in wm8960_hw_params
is not necessary and it causes above issue.

Fixes: 3176bf2d7ccd ("ASoC: wm8960: update pll and clock setting function")
Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/1587468525-27514-1-git-send-email-shengjiu.wang@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Merge tag 'kvm-ppc-fixes-5.7-1' of git://git./linux/kernel/git/paulus/powerpc into kvm-master

PPC KVM fix for 5.7

- Fix a regression introduced in the last merge window, which results
in guests in HPT mode dying randomly.

Merge tag 'kvm-s390-master-5.7-2' of git://git./linux/kernel/git/kvms390/linux into kvm-master

KVM: s390: Fix for 5.7 and maintainer update

- Silence false positive lockdep warning
- add Claudio as reviewer

Merge tag 'zynqmp-soc-for-v5.7-rc3' of https://github.com/Xilinx/linux-xlnx into arm/fixes

arm64: soc: ZynqMP SoC fixes for v5.7

- Fix firmware driver dependency
- Fix one spare warning in firmware driver

* tag 'zynqmp-soc-for-v5.7-rc3' of https://github.com/Xilinx/linux-xlnx:
firmware: xilinx: make firmware_debugfs_root static
drivers: soc: xilinx: fix firmware driver Kconfig dependency

Link: https://lore.kernel.org/r/4c6daeb0-bc61-8bdb-6ed6-5f58cd915326@monstr.eu
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ALSA: usx2y: Fix potential NULL dereference

The error handling code in usX2Y_rate_set() may hit a potential NULL
dereference when an error occurs before allocating all us->urb[].
Add a proper NULL check for fixing the corner case.

Reported-by: Lin Yi <teroincn@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200420075529.27203-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: usb-audio: Add quirk for Focusrite Scarlett 2i2

Force it to use asynchronous playback.

Same quirk has already been added for Focusrite Scarlett Solo (2nd gen)
with a commit 46f5710f0b88 ("ALSA: usb-audio: Add quirk for Focusrite
Scarlett Solo").

This also seems to prevent regular clicks when playing at 44100Hz
on Scarlett 2i2 (2nd gen). I did not notice any side effects.

Moved both quirks to snd_usb_audioformat_attributes_quirk() as suggested.

Signed-off-by: Gregor Pintar <grpintar@gmail.com>
Reviewed-by: Alexander Tsoy <alexander@tsoy.me>
Link: https://lore.kernel.org/r/20200420214030.2361-1-grpintar@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>

KVM: PPC: Book3S HV: Handle non-present PTEs in page fault functions

Since cd758a9b57ee "KVM: PPC: Book3S HV: Use __gfn_to_pfn_memslot in HPT
page fault handler", it's been possible in fairly rare circumstances to
load a non-present PTE in kvmppc_book3s_hv_page_fault() when running a
guest on a POWER8 host.

Because that case wasn't checked for, we could misinterpret the non-present
PTE as being a cache-inhibited PTE.  That could mismatch with the
corresponding hash PTE, which would cause the function to fail with -EFAULT
a little further down.  That would propagate up to the KVM_RUN ioctl()
generally causing the KVM userspace (usually qemu) to fall over.

This addresses the problem by catching that case and returning to the guest
instead.

For completeness, this fixes the radix page fault handler in the same
way.  For radix this didn't cause any obvious misbehaviour, because we
ended up putting the non-present PTE into the guest's partition-scoped
page tables, leading immediately to another hypervisor data/instruction
storage interrupt, which would go through the page fault path again
and fix things up.

Fixes: cd758a9b57ee "KVM: PPC: Book3S HV: Use __gfn_to_pfn_memslot in HPT page fault handler"
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1820402
Reported-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

kvm: Disable objtool frame pointer checking for vmenter.S

Frame pointers are completely broken by vmenter.S because it clobbers
RBP:

arch/x86/kvm/svm/vmenter.o: warning: objtool: __svm_vcpu_run()+0xe4: BP used as a scratch register

That's unavoidable, so just skip checking that file when frame pointers
are configured in.

On the other hand, ORC can handle that code just fine, so leave objtool
enabled in the !FRAME_POINTER case.

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Message-Id: <01fae42917bacad18be8d2cbc771353da6603473.1587398610.git.jpoimboe@redhat.com>
Tested-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Fixes: 199cd1d7b534 ("KVM: SVM: Split svm_vcpu_run inline assembly to separate file")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

audit: check the length of userspace generated audit records

Commit 756125289285 ("audit: always check the netlink payload length
in audit_receive_msg()") fixed a number of missing message length
checks, but forgot to check the length of userspace generated audit
records. The good news is that you need CAP_AUDIT_WRITE to submit
userspace audit records, which is generally only given to trusted
processes, so the impact should be limited.

Cc: stable@vger.kernel.org
Fixes: 756125289285 ("audit: always check the netlink payload length in audit_receive_msg()")
Reported-by: syzbot+49e69b4d71a420ceda3e@syzkaller.appspotmail.com
Signed-off-by: Paul Moore <paul@paul-moore.com>

tpm/tpm_tis: Free IRQ if probing fails

Call disable_interrupts() if we have to revert to polling in order not to
unnecessarily reserve the IRQ for the life-cycle of the driver.

Cc: stable@vger.kernel.org # 4.5.x
Reported-by: Hans de Goede <hdegoede@redhat.com>
Fixes: e3837e74a06d ("tpm_tis: Refactor the interrupt setup")
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

tpm: fix wrong return value in tpm_pcr_extend

For the algorithm that does not match the bank, a positive
value EINVAL is returned here. I think this is a typo error.
It is necessary to return an error value.

Cc: stable@vger.kernel.org # 5.4.x
Fixes: 9f75c8224631 ("KEYS: trusted: correctly initialize digests and fix locking issue")
Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Reviewed-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

tpm: ibmvtpm: retry on H_CLOSED in tpm_ibmvtpm_send()

tpm_ibmvtpm_send() can fail during PowerVM Live Partition Mobility resume
with an H_CLOSED return from ibmvtpm_send_crq(). The PAPR says, 'The
"partner partition suspended" transport event disables the associated CRQ
such that any H_SEND_CRQ hcall() to the associated CRQ returns H_Closed
until the CRQ has been explicitly enabled using the H_ENABLE_CRQ hcall.'
This patch adds a check in tpm_ibmvtpm_send() for an H_CLOSED return from
ibmvtpm_send_crq() and in that case calls tpm_ibmvtpm_resume() and
retries the ibmvtpm_send_crq() once.

Cc: stable@vger.kernel.org # 3.7.x
Fixes: 132f76294744 ("drivers/char/tpm: Add new device driver to support IBM vTPM")
Reported-by: Linh Pham <phaml@us.ibm.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: George Wilson <gcwilson@linux.ibm.com>
Tested-by: Linh Pham <phaml@us.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

tpm: Export tpm2_get_cc_attrs_tbl for ibmvtpm driver as module

This patch fixes the following problem when the ibmvtpm driver
is built as a module:

ERROR: modpost: "tpm2_get_cc_attrs_tbl" [drivers/char/tpm/tpm_ibmvtpm.ko] undefined!
make[1]: *** [scripts/Makefile.modpost:94: __modpost] Error 1
make: *** [Makefile:1298: modules] Error 2

Fixes: 18b3670d79ae ("tpm: ibmvtpm: Add support for TPM2")
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

Merge tag 'omap-for-v5.6/fixes-rc7-signed' of git://git./linux/kernel/git/tmlind/linux-omap into arm/fixes

Boot regression fix for N950/N9

We need to tag RNG as disabled for N950/N9 as it blocked by the secure
mode. We have a similar change done for N900, but I missed adding it
for N950/N9 with the recent RNG changes.

* tag 'omap-for-v5.6/fixes-rc7-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
ARM: dts: OMAP3: disable RNG on N950/N9

Link: https://lore.kernel.org/r/pull-1585340588-558327@atomide.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

drm/i915/dpcd_bl: Unbreak enable_dpcd_backlight modparam

Looks like I accidentally made it so you couldn't force DPCD backlight
support on, whoops. Fix that.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Fixes: 17f5d57915be ("drm/i915: Force DPCD backlight mode on X1 Extreme 2nd Gen 4K AMOLED panel")
Cc: Adam Jackson <ajax@redhat.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: "Ville Syrjälä" <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200413214407.1851002-1-lyude@redhat.com
(cherry picked from commit d7fb38ae36a2dc97924b075ad1d1a88792777ea9)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drm/i915: fix Sphinx build duplicate label warning

Fix the warning caused by enabling the autosectionlabel extension in the
kernel Sphinx build:

Documentation/gpu/i915.rst:610: WARNING: duplicate label
gpu/i915:layout, other instance in Documentation/gpu/i915.rst

The autosectionlabel extension adds labels to each section title for
cross-referencing, but forbids identical section titles in a
document. With kernel-doc, this includes sections titles in the included
kernel-doc comments.

In the warning message, Sphinx is unable to reference the labels in
their true locations in the kernel-doc comments in source. In this case,
there's "Layout" sections in both gt/intel_workarounds.c and
i915_reg.h. Rename the section in the latter to "File Layout".

Fixes: 58ad30cf91f0 ("docs: fix reference to core-api/namespaces.rst")
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200417130109.12791-1-jani.nikula@intel.com
(cherry picked from commit 27be41de45a70fe1cb0ae1cbd2fd6da1ce3ffe9a)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drm/i915/display: Load DP_TP_CTL/STATUS offset before use it

Right now dp.regs.dp_tp_ctl/status are only set during the encoder
pre_enable() hook, what is causing all reads and writes to those
registers to go to offset 0x0 before pre_enable() is executed.

So if i915 takes the BIOS state and don't do a modeset any following
link retraing will fail.

In the case that i915 needs to do a modeset, the DDI disable sequence
will write to a wrong register not disabling DP 'Transport Enable' in
DP_TP_CTL, making a HDMI modeset in the same port/transcoder to
not light up the monitor.

So here for GENs older than 12, that have those registers fixed at
port offset range it is loading at encoder/port init while for GEN12
it will keep setting it at encoder pre_enable() and during HW state
readout.

Fixes: 4444df6e205b ("drm/i915/tgl: move DP_TP_* to transcoder")
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200414230442.262092-1-jose.souza@intel.com
(cherry picked from commit edcb9028d66b44d74ba4f8b9daa379b004dc1f85)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drm/i915/tgl: TBT AUX should use TC power well ops

As on ICL, we want to use the Type-C aux handlers for the TBT aux wells
to ensure the DP_AUX_CH_CTL_TBT_IO flag is set properly.

Fixes: 656409bbaf87 ("drm/i915/tgl: Add power well support")
Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200415233435.3064257-1-matthew.d.roper@intel.com
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
(cherry picked from commit 3cbdb97564a39020262e62b655e788b63cf426cb)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drm/i915: HDCP: fix Ri prime check done during link check

The check was always succeeding even in case of a mismatch due to the
HDCP_STATUS_ENC bit being set. Make sure both bits are actually set.

Signed-off-by: Oliver Barta <oliver.barta@aptiv.com>
Fixes: 2320175feb74 ("drm/i915: Implement HDCP for HDMI")
Reviewed-by: Ramalingam C <ramalingam.c@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200328104100.12162-1-oliver.barta@aptiv.com
(cherry picked from commit 3ffaf56e912e76cf09c560244c8804f9bebda8b1)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drm/i915/gt: Update PMINTRMSK holding fw

If we use a non-forcewaked write to PMINTRMSK, it does not take effect
until much later, if at all, causing a loss of RPS interrupts and no GPU
reclocking, leaving the GPU running at the wrong frequency for long
periods of time.

Reported-by: Francisco Jerez <currojerez@riseup.net>
Suggested-by: Francisco Jerez <currojerez@riseup.net>
Fixes: 35cc7f32c298 ("drm/i915/gt: Use non-forcewake writes for RPS")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Francisco Jerez <currojerez@riseup.net>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Andi Shyti <andi.shyti@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
Cc: <stable@vger.kernel.org> # v5.6+
Link: https://patchwork.freedesktop.org/patch/msgid/20200415170318.16771-2-chris@chris-wilson.co.uk
(cherry picked from commit a080bd994c4023042a2b605c65fa10a25933f636)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drm/i915/tgl: Add Wa_14010477008:tgl

Media decompression support should not be advertised on any display
planes for steppings A0-C0.

Bspec: 53273
Fixes: 2dfbf9d2873a ("drm/i915/tgl: Gen-12 display can decompress surfaces compressed by the media engine")
Cc: Matt Atwood <matthew.s.atwood@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200414211118.2787489-3-matthew.d.roper@intel.com
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
(cherry picked from commit dbff5a8db9c630f61a892ab41a283445e01270f5)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

bdev: Reduce time holding bd_mutex in sync in blkdev_close()

While trying to "dd" to the block device for a USB stick, I
encountered a hung task warning (blocked for > 120 seconds).  I
managed to come up with an easy way to reproduce this on my system
(where /dev/sdb is the block device for my USB stick) with:

  while true; do dd if=/dev/zero of=/dev/sdb bs=4M; done

With my reproduction here are the relevant bits from the hung task
detector:

INFO: task udevd:294 blocked for more than 122 seconds.
...
udevd           D    0   294      1 0x00400008
Call trace:
  ...
  mutex_lock_nested+0x40/0x50
  __blkdev_get+0x7c/0x3d4
  blkdev_get+0x118/0x138
  blkdev_open+0x94/0xa8
  do_dentry_open+0x268/0x3a0
  vfs_open+0x34/0x40
  path_openat+0x39c/0xdf4
  do_filp_open+0x90/0x10c
  do_sys_open+0x150/0x3c8
  ...

...
Showing all locks held in the system:
...
1 lock held by dd/2798:
  #0: ffffff814ac1a3b8 (&bdev->bd_mutex){+.+.}, at: __blkdev_put+0x50/0x204
...
dd              D    0  2798   2764 0x00400208
Call trace:
  ...
  schedule+0x8c/0xbc
  io_schedule+0x1c/0x40
  wait_on_page_bit_common+0x238/0x338
  __lock_page+0x5c/0x68
  write_cache_pages+0x194/0x500
  generic_writepages+0x64/0xa4
  blkdev_writepages+0x24/0x30
  do_writepages+0x48/0xa8
  __filemap_fdatawrite_range+0xac/0xd8
  filemap_write_and_wait+0x30/0x84
  __blkdev_put+0x88/0x204
  blkdev_put+0xc4/0xe4
  blkdev_close+0x28/0x38
  __fput+0xe0/0x238
  ____fput+0x1c/0x28
  task_work_run+0xb0/0xe4
  do_notify_resume+0xfc0/0x14bc
  work_pending+0x8/0x14

The problem appears related to the fact that my USB disk is terribly
slow and that I have a lot of RAM in my system to cache things.
Specifically my writes seem to be happening at ~15 MB/s and I've got
~4 GB of RAM in my system that can be used for buffering.  To write 4
GB of buffer to disk thus takes ~4000 MB / ~15 MB/s = ~267 seconds.

The 267 second number is a problem because in __blkdev_put() we call
sync_blockdev() while holding the bd_mutex.  Any other callers who
want the bd_mutex will be blocked for the whole time.

The problem is made worse because I believe blkdev_put() specifically
tells other tasks (namely udev) to go try to access the device at right
around the same time we're going to hold the mutex for a long time.

Putting some traces around this (after disabling the hung task detector),
I could confirm:
dd:    437.608600: __blkdev_put() right before sync_blockdev() for sdb
udevd: 437.623901: blkdev_open() right before blkdev_get() for sdb
dd:    661.468451: __blkdev_put() right after sync_blockdev() for sdb
udevd: 663.820426: blkdev_open() right after blkdev_get() for sdb

A simple fix for this is to realize that sync_blockdev() works fine if
you're not holding the mutex.  Also, it's not the end of the world if
you sync a little early (though it can have performance impacts).
Thus we can make a guess that we're going to need to do the sync and
then do it without holding the mutex.  We still do one last sync with
the mutex but it should be much, much faster.

With this, my hung task warnings for my test case are gone.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

ASoC: wm89xx: Add missing dependency

sound/soc/codecs/wm8900.o: In function `wm8900_i2c_probe':
wm8900.c:(.text+0xa36): undefined reference to `__devm_regmap_init_i2c'
sound/soc/codecs/wm8900.o: In function `wm8900_modinit':
wm8900.c:(.init.text+0xb): undefined reference to `i2c_register_driver'
sound/soc/codecs/wm8900.o: In function `wm8900_exit':
wm8900.c:(.exit.text+0x8): undefined reference to `i2c_del_driver'
sound/soc/codecs/wm8988.o: In function `wm8988_i2c_probe':
wm8988.c:(.text+0x857): undefined reference to `__devm_regmap_init_i2c'
sound/soc/codecs/wm8988.o: In function `wm8988_modinit':
wm8988.c:(.init.text+0xb): undefined reference to `i2c_register_driver'
sound/soc/codecs/wm8988.o: In function `wm8988_exit':
wm8988.c:(.exit.text+0x8): undefined reference to `i2c_del_driver'
sound/soc/codecs/wm8995.o: In function `wm8995_i2c_probe':
wm8995.c:(.text+0x1c4f): undefined reference to `__devm_regmap_init_i2c'
sound/soc/codecs/wm8995.o: In function `wm8995_modinit':
wm8995.c:(.init.text+0xb): undefined reference to `i2c_register_driver'
sound/soc/codecs/wm8995.o: In function `wm8995_exit':
wm8995.c:(.exit.text+0x8): undefined reference to `i2c_del_driver'

Add SND_SOC_I2C_AND_SPI dependency to fix this.

Fixes: ea00d95200d02ece ("ASoC: Use imply for SND_SOC_ALL_CODECS")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20200420125343.20920-1-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

vhost: disable for OABI

vhost is currently broken on the some ARM configs.

The reason is that the ring element addresses are passed between
components with different alignments assumptions. Thus, if
guest selects a pointer and host then gets and dereferences
it, then alignment assumed by the host's compiler might be
greater than the actual alignment of the pointer.
compiler on the host from assuming pointer is aligned.

This actually triggers on ARM with -mabi=apcs-gnu - which is a
deprecated configuration. With this OABI, compiler assumes that
all structures are 4 byte aligned - which is stronger than
virtio guarantees for available and used rings, which are
merely 2 bytes. Thus a guest without -mabi=apcs-gnu running
on top of host with -mabi=apcs-gnu will be broken.

The correct fix is to force alignment of structures - however
that is an intrusive fix that's best deferred until the next release.

We didn't previously support such ancient systems at all - this surfaced
after vdpa support prompted removing dependency of vhost on
VIRTULIZATION. So for now, let's just add something along the lines of

depends on !ARM || AEABI

to the virtio Kconfig declaration, and add a comment that it has to do
with struct member alignment.

Note: we can't make VHOST and VHOST_RING themselves have
a dependency since these are selected. Add a new symbol for that.

We should be able to drop this dependency down the road.

Fixes: 20c384f1ea1a0bc7 ("vhost: refine vhost and vringh kconfig")
Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Suggested-by: Richard Earnshaw <Richard.Earnshaw@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>