Since commit 1b6b26ae ("pipe: fix and clarify pipe write wakeup
logic") we have sanitized the pipe write logic, and would only try to
wake up readers if they needed it.

In particular, if the pipe already had data in it before the write,
there was no point in trying to wake up a reader, since any existing
readers must have been aware of the pre-existing data already.  Doing
extraneous wakeups will only cause potential thundering herd problems.

However, it turns out that some Android libraries have misused the EPOLL
interface, and expected "edge triggered" be to "any new write will
trigger it".  Even if there was no edge in sight.

Quoting Sandeep Patil:
 "The commit 1b6b26ae ('pipe: fix and clarify pipe write wakeup
  logic') changed pipe write logic to wakeup readers only if the pipe
  was empty at the time of write. However, there are libraries that
  relied upon the older behavior for notification scheme similar to
  what's described in [1]

  One such library 'realm-core'[2] is used by numerous Android
  applications. The library uses a similar notification mechanism as GNU
  Make but it never drains the pipe until it is full. When Android moved
  to v5.10 kernel, all applications using this library stopped working.

  The library has since been fixed[3] but it will be a while before all
  applications incorporate the updated library"

Our regression rule for the kernel is that if applications break from
new behavior, it's a regression, even if it was because the application
did something patently wrong.  Also note the original report [4] by
Michal Kerrisk about a test for this epoll behavior - but at that point
we didn't know of any actual broken use case.

So add the extraneous wakeup, to approximate the old behavior.

[ I say "approximate", because the exact old behavior was to do a wakeup
  not for each write(), but for each pipe buffer chunk that was filled
  in. The behavior introduced by this change is not that - this is just
  "every write will cause a wakeup, whether necessary or not", which
  seems to be sufficient for the broken library use. ]

It's worth noting that this adds the extraneous wakeup only for the
write side, while the read side still considers the "edge" to be purely
about reading enough from the pipe to allow further writes.

See commit f467a6a6 ("pipe: fix and clarify pipe read wakeup logic")
for the pipe read case, which remains that "only wake up if the pipe was
full, and we read something from it".

Link: https://lore.kernel.org/lkml/CAHk-=wjeG0q1vgzu4iJhW5juPkTsjTYmiqiMUYAebWW+0bam6w@mail.gmail.com/ [1]
Link: https://github.com/realm/realm-core [2]
Link: https://github.com/realm/realm-core/issues/4666 [3]
Link: https://lore.kernel.org/lkml/CAKgNAkjMBGeAwF=2MKK758BhxvW58wYTgYKB2V-gY1PwXxrH+Q@mail.gmail.com/ [4]
Link: https://lore.kernel.org/lkml/20210729222635.2937453-1-sspatil@android.com/Reported-by: Sandeep Patil <sspatil@android.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull block fixes from Jens Axboe:

 - gendisk freeing fix (Christoph)

 - blk-iocost wake ordering fix (Tejun)

 - tag allocation error handling fix (John)

 - loop locking fix. While this isn't the prettiest fix in the world,
   nobody has any good alternatives for 5.14. Something to likely
   revisit for 5.15. (Tetsuo)

* tag 'block-5.14-2021-07-30' of git://git.kernel.dk/linux-block:
  block: delay freeing the gendisk
  blk-iocost: fix operation ordering in iocg_wake_fn()
  blk-mq-sched: Fix blk_mq_sched_alloc_tags() error handling
  loop: reintroduce global lock for safe loop_validate_file() traversal

Pull io_uring fixes from Jens Axboe:

 - A fix for block backed reissue (me)

 - Reissue context hardening (me)

 - Async link locking fix (Pavel)

* tag 'io_uring-5.14-2021-07-30' of git://git.kernel.dk/linux-block:
  io_uring: fix poll requests leaking second poll entries
  io_uring: don't block level reissue off completion path
  io_uring: always reissue from task_work context
  io_uring: fix race in unified task_work running
  io_uring: fix io_prep_async_link locking

Pull libata fixlets from Jens Axboe:

 - A fix for PIO highmem (Christoph)

 - Kill HAVE_IDE as it's now unused (Lukas)

* tag 'libata-5.14-2021-07-30' of git://git.kernel.dk/linux-block:
  arch: Kconfig: clean up obsolete use of HAVE_IDE
  libata: fix ata_pio_sector for CONFIG_HIGHMEM

Pull btrfs fixes from David Sterba:

 - fix -Warray-bounds warning, to help external patchset to make it
   default treewide

 - fix writeable device accounting (syzbot report)

 - fix fsync and log replay after a rename and inode eviction

 - fix potentially lost error code when submitting multiple bios for
   compressed range

* tag 'for-5.14-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: calculate number of eb pages properly in csum_tree_block
  btrfs: fix rw device counting in __btrfs_free_extra_devids
  btrfs: fix lost inode on log replay after mix of fsync, rename and inode eviction
  btrfs: mark compressed range uptodate only if all bio succeed

Pull HID fixes from Jiri Kosina:

 - resume timing fix for intel-ish driver (Ye Xiang)

 - fix for using incorrect MMIO register in amd_sfh driver (Dylan
   MacKenzie)

 - Cintiq 24HDT / 27QHDT regression fix and touch processing fix for
   Wacom driver (Jason Gerecke)

 - device removal bugfix for ft260 driver (Michael Zaidman)

 - other small assorted fixes

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid:
  HID: ft260: fix device removal due to USB disconnect
  HID: wacom: Skip processing of touches with negative slot values
  HID: wacom: Re-enable touch by default for Cintiq 24HDT / 27QHDT
  HID: Kconfig: Fix spelling mistake "Uninterruptable" -> "Uninterruptible"
  HID: apple: Add support for Keychron K1 wireless keyboard
  HID: fix typo in Kconfig
  HID: ft260: fix format type warning in ft260_word_show()
  HID: amd_sfh: Use correct MMIO register for DMA address
  HID: asus: Remove check for same LED brightness on set
  HID: intel-ish-hid: use async resume function

Merge misc fixes from Andrew Morton:
 "7 patches.

  Subsystems affected by this patch series: lib, ocfs2, and mm (slub,
  migration, and memcg)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm/memcg: fix NULL pointer dereference in memcg_slab_free_hook()
  slub: fix unreclaimable slab stat for bulk free
  mm/migrate: fix NR_ISOLATED corruption on 64-bit
  mm: memcontrol: fix blocking rstat function called from atomic cgroup1 thresholding code
  ocfs2: issue zeroout to EOF blocks
  ocfs2: fix zero out valid data
  lib/test_string.c: move string selftest in the Runtime Testing menu

When I use kfree_rcu() to free a large memory allocated by kmalloc_node(),
the following dump occurs.

  BUG: kernel NULL pointer dereference, address: 0000000000000020
  [...]
  Oops: 0000 [#1] SMP
  [...]
  Workqueue: events kfree_rcu_work
  RIP: 0010:__obj_to_index include/linux/slub_def.h:182 [inline]
  RIP: 0010:obj_to_index include/linux/slub_def.h:191 [inline]
  RIP: 0010:memcg_slab_free_hook+0x120/0x260 mm/slab.h:363
  [...]
  Call Trace:
    kmem_cache_free_bulk+0x58/0x630 mm/slub.c:3293
    kfree_bulk include/linux/slab.h:413 [inline]
    kfree_rcu_work+0x1ab/0x200 kernel/rcu/tree.c:3300
    process_one_work+0x207/0x530 kernel/workqueue.c:2276
    worker_thread+0x320/0x610 kernel/workqueue.c:2422
    kthread+0x13d/0x160 kernel/kthread.c:313
    ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

When kmalloc_node() a large memory, page is allocated, not slab, so when
freeing memory via kfree_rcu(), this large memory should not be used by
memcg_slab_free_hook(), because memcg_slab_free_hook() is is used for
slab.

Using page_objcgs_check() instead of page_objcgs() in
memcg_slab_free_hook() to fix this bug.

Link: https://lkml.kernel.org/r/20210728145655.274476-1-wanghai38@huawei.com
Fixes: 270c6a71 ("mm: memcontrol/slab: Use helpers to access slab page's memcg_data")
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.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>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

SLUB uses page allocator for higher order allocations and update
unreclaimable slab stat for such allocations.  At the moment, the bulk
free for SLUB does not share code with normal free code path for these
type of allocations and have missed the stat update.  So, fix the stat
update by common code.  The user visible impact of the bug is the
potential of inconsistent unreclaimable slab stat visible through
meminfo and vmstat.

Link: https://lkml.kernel.org/r/20210728155354.3440560-1-shakeelb@google.com
Fixes: 6a486c0a ("mm, sl[ou]b: improve memory accounting")
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.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>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Similar to commit 2da9f630 ("mm/vmscan: fix NR_ISOLATED_FILE
corruption on 64-bit") avoid using unsigned int for nr_pages.  With
unsigned int type the large unsigned int converts to a large positive
signed long.

Symptoms include CMA allocations hanging forever due to
alloc_contig_range->...->isolate_migratepages_block waiting forever in
"while (unlikely(too_many_isolated(pgdat)))".

Link: https://lkml.kernel.org/r/20210728042531.359409-1-aneesh.kumar@linux.ibm.com
Fixes: c5fc5c3a ("mm: migrate: account THP NUMA migration counters correctly")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Dan Carpenter reports:

    The patch 2d146aa3: "mm: memcontrol: switch to rstat" from Apr
    29, 2021, leads to the following static checker warning:

	    kernel/cgroup/rstat.c:200 cgroup_rstat_flush()
	    warn: sleeping in atomic context

    mm/memcontrol.c
      3572  static unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap)
      3573  {
      3574          unsigned long val;
      3575
      3576          if (mem_cgroup_is_root(memcg)) {
      3577                  cgroup_rstat_flush(memcg->css.cgroup);
			    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

    This is from static analysis and potentially a false positive.  The
    problem is that mem_cgroup_usage() is called from __mem_cgroup_threshold()
    which holds an rcu_read_lock().  And the cgroup_rstat_flush() function
    can sleep.

      3578                  val = memcg_page_state(memcg, NR_FILE_PAGES) +
      3579                          memcg_page_state(memcg, NR_ANON_MAPPED);
      3580                  if (swap)
      3581                          val += memcg_page_state(memcg, MEMCG_SWAP);
      3582          } else {
      3583                  if (!swap)
      3584                          val = page_counter_read(&memcg->memory);
      3585                  else
      3586                          val = page_counter_read(&memcg->memsw);
      3587          }
      3588          return val;
      3589  }

__mem_cgroup_threshold() indeed holds the rcu lock.  In addition, the
thresholding code is invoked during stat changes, and those contexts
have irqs disabled as well.  If the lock breaking occurs inside the
flush function, it will result in a sleep from an atomic context.

Use the irqsafe flushing variant in mem_cgroup_usage() to fix this.

Link: https://lkml.kernel.org/r/20210726150019.251820-1-hannes@cmpxchg.org
Fixes: 2d146aa3 ("mm: memcontrol: switch to rstat")
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Chris Down <chris@chrisdown.name>
Reviewed-by: Rik van Riel <riel@surriel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

For punch holes in EOF blocks, fallocate used buffer write to zero the
EOF blocks in last cluster.  But since ->writepage will ignore EOF
pages, those zeros will not be flushed.

This "looks" ok as commit 6bba4471 ("ocfs2: fix data corruption by
fallocate") will zero the EOF blocks when extend the file size, but it
isn't.  The problem happened on those EOF pages, before writeback, those
pages had DIRTY flag set and all buffer_head in them also had DIRTY flag
set, when writeback run by write_cache_pages(), DIRTY flag on the page
was cleared, but DIRTY flag on the buffer_head not.

When next write happened to those EOF pages, since buffer_head already
had DIRTY flag set, it would not mark page DIRTY again.  That made
writeback ignore them forever.  That will cause data corruption.  Even
directio write can't work because it will fail when trying to drop pages
caches before direct io, as it found the buffer_head for those pages
still had DIRTY flag set, then it will fall back to buffer io mode.

To make a summary of the issue, as writeback ingores EOF pages, once any
EOF page is generated, any write to it will only go to the page cache,
it will never be flushed to disk even file size extends and that page is
not EOF page any more.  The fix is to avoid zero EOF blocks with buffer
write.

The following code snippet from qemu-img could trigger the corruption.

  656   open("6b3711ae-3306-4bdd-823c-cf1c0060a095.conv.2", O_RDWR|O_DIRECT|O_CLOEXEC) = 11
  ...
  660   fallocate(11, FALLOC_FL_KEEP_SIZE|FALLOC_FL_PUNCH_HOLE, 2275868672, 327680 <unfinished ...>
  660   fallocate(11, 0, 2275868672, 327680) = 0
  658   pwrite64(11, "

Link: https://lkml.kernel.org/r/20210722054923.24389-2-junxiao.bi@oracle.comSigned-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

If append-dio feature is enabled, direct-io write and fallocate could
run in parallel to extend file size, fallocate used "orig_isize" to
record i_size before taking "ip_alloc_sem", when
ocfs2_zeroout_partial_cluster() zeroout EOF blocks, i_size maybe already
extended by ocfs2_dio_end_io_write(), that will cause valid data zeroed
out.

Link: https://lkml.kernel.org/r/20210722054923.24389-1-junxiao.bi@oracle.com
Fixes: 6bba4471 ("ocfs2: fix data corruption by fallocate")
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

STRING_SELFTEST is presented in the "Library routines" menu.  Move it in
Kernel hacking > Kernel Testing and Coverage > Runtime Testing together
with other similar tests found in lib/

	--- Runtime Testing
	<*>   Test functions located in the hexdump module at runtime
	<*>   Test string functions (NEW)
	<*>   Test functions located in the string_helpers module at runtime
	<*>   Test strscpy*() family of functions at runtime
	<*>   Test kstrto*() family of functions at runtime
	<*>   Test printf() family of functions at runtime
	<*>   Test scanf() family of functions at runtime

Link: https://lkml.kernel.org/r/20210719185158.190371-1-mcroce@linux.microsoft.comSigned-off-by: Matteo Croce <mcroce@microsoft.com>
Cc: Peter Rosin <peda@axentia.se>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The arch-specific Kconfig files use HAVE_IDE to indicate if IDE is
supported.

As IDE support and the HAVE_IDE config vanishes with commit b7fb14d3
("ide: remove the legacy ide driver"), there is no need to mention
HAVE_IDE in all those arch-specific Kconfig files.

The issue was identified with ./scripts/checkkconfigsymbols.py.

Fixes: b7fb14d3 ("ide: remove the legacy ide driver")
Suggested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20210728182115.4401-1-lukas.bulwahn@gmail.comReviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull drm fixes from Dave Airlie:
 "Regular drm fixes pull, seems about the right size, lots of small
  fixes across the board, mostly amdgpu, but msm and i915 are in there
  along with panel and ttm.

  amdgpu:
   - Fix resource leak in an error path
   - Avoid stack contents exposure in error path
   - pmops check fix for S0ix vs S3
   - DCN 2.1 display fixes
   - DCN 2.0 display fix
   - Backlight control fix for laptops with HDR panels
   - Maintainers updates

  i915:
   - Fix vbt port mask
   - Fix around reading the right DSC disable fuse in display_ver 10
   - Split display version 9 and 10 in intel_setup_outputs

  msm:
   - iommu fault display fix
   - misc dp compliance fixes
   - dpu reg sizing fix

  panel:
   - Fix bpc for ytc700tlag_05_201c

  ttm:
   - debugfs init fixes"

* tag 'drm-fixes-2021-07-30' of git://anongit.freedesktop.org/drm/drm:
  maintainers: add bugs and chat URLs for amdgpu
  drm/amdgpu/display: only enable aux backlight control for OLED panels
  drm/amd/display: ensure dentist display clock update finished in DCN20
  drm/amd/display: Add missing DCN21 IP parameter
  drm/amd/display: Guard DST_Y_PREFETCH register overflow in DCN21
  drm/amdgpu: Check pmops for desired suspend state
  drm/msm/dp: Initialize dp->aux->drm_dev before registration
  drm/msm/dp: signal audio plugged change at dp_pm_resume
  drm/msm/dp: Initialize the INTF_CONFIG register
  drm/msm/dp: use dp_ctrl_off_link_stream during PHY compliance test run
  drm/msm: Fix display fault handling
  drm/msm/dpu: Fix sm8250_mdp register length
  drm/amdgpu: Avoid printing of stack contents on firmware load error
  drm/amdgpu: Fix resource leak on probe error path
  drm/i915/display: split DISPLAY_VER 9 and 10 in intel_setup_outputs()
  drm/i915: fix not reading DSC disable fuse in GLK
  drm/i915/bios: Fix ports mask
  drm/panel: panel-simple: Fix proper bpc for ytc700tlag_05_201c
  drm/ttm: Initialize debugfs from ttm_global_init()

Merge tag 'fallthrough-fixes-clang-5.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux

Pull fallthrough fixes from Gustavo Silva:
 "Fix some fall-through warnings when building with Clang and
  '-Wimplicit-fallthrough' on ARM"

* tag 'fallthrough-fixes-clang-5.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux:
  scsi: fas216: Fix fall-through warning for Clang
  scsi: acornscsi: Fix fall-through warning for clang
  ARM: riscpc: Fix fall-through warning for Clang

Pull alpha updates from Matt Turner:
 "They're mostly small janitorial fixes but there's also more important
  ones:

   - drop the alpha-specific x86 binary loader (David Hildenbrand)

   - regression fix for at least Marvel platforms (Mike Rapoport)

   - fix for a scary-looking typo (Zheng Yongjun)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mattst88/alpha:
  alpha: register early reserved memory in memblock
  alpha: fix spelling mistakes
  alpha: Remove space between * and parameter name
  alpha: fp_emul: avoid init/cleanup_module names
  alpha: Add syscall_get_return_value()
  binfmt: remove support for em86 (alpha only)
  alpha: fix typos in a comment
  alpha: defconfig: add necessary configs for boot testing
  alpha: Send stop IPI to send to online CPUs
  alpha: convert comma to semicolon
  alpha: remove undef inline in compiler.h
  alpha: Kconfig: Replace HTTP links with HTTPS ones
  alpha: __udiv_qrnnd should be exported

Fix the following fallthrough warning (on ARM):

drivers/scsi/arm/fas216.c:1379:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
           default:
           ^
   drivers/scsi/arm/fas216.c:1379:2: note: insert 'break;' to avoid fall-through
           default:
           ^
           break;
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/lkml/202107260355.bF00i5bi-lkp@intel.com/Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Fix the following fallthrough warning (on ARM):

drivers/scsi/arm/acornscsi.c:2651:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
           case res_success:
           ^
   drivers/scsi/arm/acornscsi.c:2651:2: note: insert '__attribute__((fallthrough));' to silence this warning
           case res_success:
           ^
           __attribute__((fallthrough));
   drivers/scsi/arm/acornscsi.c:2651:2: note: insert 'break;' to avoid fall-through
           case res_success:
           ^
           break;
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/lkml/202107260355.bF00i5bi-lkp@intel.com/Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Fix the following fallthrough warning:

arch/arm/mach-rpc/riscpc.c:52:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
           default:
           ^
arch/arm/mach-rpc/riscpc.c:52:2: note: insert 'break;' to avoid fall-through
           default:
           ^
           break;
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/lkml/202107260355.bF00i5bi-lkp@intel.com/Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Pull kvm fixes from Paolo Bonzini:
 "ARM:

   - Fix MTE shared page detection

   - Enable selftest's use of PMU registers when asked to

  s390:

   - restore 5.13 debugfs names

  x86:

   - fix sizes for vcpu-id indexed arrays

   - fixes for AMD virtualized LAPIC (AVIC)

   - other small bugfixes

  Generic:

   - access tracking performance test

   - dirty_log_perf_test command line parsing fix

   - Fix selftest use of obsolete pthread_yield() in favour of
     sched_yield()

   - use cpu_relax when halt polling

   - fixed missing KVM_CLEAR_DIRTY_LOG compat ioctl"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: add missing compat KVM_CLEAR_DIRTY_LOG
  KVM: use cpu_relax when halt polling
  KVM: SVM: use vmcb01 in svm_refresh_apicv_exec_ctrl
  KVM: SVM: tweak warning about enabled AVIC on nested entry
  KVM: SVM: svm_set_vintr don't warn if AVIC is active but is about to be deactivated
  KVM: s390: restore old debugfs names
  KVM: SVM: delay svm_vcpu_init_msrpm after svm->vmcb is initialized
  KVM: selftests: Introduce access_tracking_perf_test
  KVM: selftests: Fix missing break in dirty_log_perf_test arg parsing
  x86/kvm: fix vcpu-id indexed array sizes
  KVM: x86: Check the right feature bit for MSR_KVM_ASYNC_PF_ACK access
  docs: virt: kvm: api.rst: replace some characters
  KVM: Documentation: Fix KVM_CAP_ENFORCE_PV_FEATURE_CPUID name
  KVM: nSVM: Swap the parameter order for svm_copy_vmrun_state()/svm_copy_vmloadsave_state()
  KVM: nSVM: Rename nested_svm_vmloadsave() to svm_copy_vmloadsave_state()
  KVM: arm64: selftests: get-reg-list: actually enable pmu regs in pmu sublist
  KVM: selftests: change pthread_yield to sched_yield
  KVM: arm64: Fix detection of shared VMAs on guest fault

Pull m68knommu fix from Greg Ungerer:
 "A single compile time fix"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
  m68k/coldfire: change pll var. to clk_pll

Building with -Warray-bounds on systems with 64K pages there's a
warning:

  fs/btrfs/disk-io.c: In function ‘csum_tree_block’:
  fs/btrfs/disk-io.c:226:34: warning: array subscript 1 is above array bounds of ‘struct page *[1]’ [-Warray-bounds]
    226 |   kaddr = page_address(buf->pages[i]);
        |                        ~~~~~~~~~~^~~
  ./include/linux/mm.h:1630:48: note: in definition of macro ‘page_address’
   1630 | #define page_address(page) lowmem_page_address(page)
        |                                                ^~~~
  In file included from fs/btrfs/ctree.h:32,
                   from fs/btrfs/disk-io.c:23:
  fs/btrfs/extent_io.h:98:15: note: while referencing ‘pages’
     98 |  struct page *pages[1];
        |               ^~~~~

The compiler has no way to know that in that case the nodesize is exactly
PAGE_SIZE, so the resulting number of pages will be correct (1).

Let's use num_extent_pages that makes the case nodesize == PAGE_SIZE
explicitly 1.
Reported-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

This commit fixes a functional regression introduced by the commit 82f09a63
("HID: ft260: improve error handling of ft260_hid_feature_report_get()")
when upon USB disconnect, the FTDI FT260 i2c device is still available within
the /dev folder.

In my company's product, where the host USB to FT260 USB connection is
hard-wired in the PCB, the issue is not reproducible. To reproduce it, I used
the VirtualBox Ubuntu 20.04 VM and the UMFT260EV1A development module for the
FTDI FT260 chip:

Plug the UMFT260EV1A module into a USB port and attach it to VM.

The VM shows 2 i2c devices under the /dev:
    michael@michael-VirtualBox:~$ ls /dev/i2c-*
    /dev/i2c-0  /dev/i2c-1

The i2c-0 is not related to the FTDI FT260:
    michael@michael-VirtualBox:~$ cat /sys/bus/i2c/devices/i2c-0/name
    SMBus PIIX4 adapter at 4100

The i2c-1 is created by hid-ft260.ko:
    michael@michael-VirtualBox:~$ cat /sys/bus/i2c/devices/i2c-1/name
    FT260 usb-i2c bridge on hidraw1

Now, detach the FTDI FT260 USB device from VM. We expect the /dev/i2c-1
to disappear, but it's still here:
    michael@michael-VirtualBox:~$ ls /dev/i2c-*
    /dev/i2c-0  /dev/i2c-1

And the kernel log shows:
    [  +0.001202] usb 2-2: USB disconnect, device number 3
    [  +0.000109] ft260 0003:0403:6030.0002: failed to retrieve system status
    [  +0.000316] ft260 0003:0403:6030.0003: failed to retrieve system status

It happens because the commit 82f09a63 changed the ft260_get_system_config()
return logic. This caused the ft260_is_interface_enabled() to exit with error
upon the FT260 device USB disconnect, which in turn, aborted the ft260_remove()
before deleting the FT260 i2c device and cleaning its sysfs stuff.

This commit restores the FT260 USB removal functionality and improves the
ft260_is_interface_enabled() code to handle correctly all chip modes defined
by the device interface configuration pins DCNF0 and DCNF1.
Signed-off-by: Michael Zaidman <michael.zaidman@gmail.com>
Acked-by: Aaron Jones (FTDI-UK) <aaron.jones@ftdichip.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

Merge tag 'amd-drm-fixes-5.14-2021-07-28' of https://gitlab.freedesktop.org/agd5f/linux into drm-fixes

amd-drm-fixes-5.14-2021-07-28:

amdgpu:
- Fix resource leak in an error path
- Avoid stack contents exposure in error path
- pmops check fix for S0ix vs S3
- DCN 2.1 display fixes
- DCN 2.0 display fix
- Backlight control fix for laptops with HDR panels
- Maintainers updates
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210729025817.4145-1-alexander.deucher@amd.com

The memory reserved by console/PALcode or non-volatile memory is not added
to memblock.memory.

Since commit fa3354e4 (mm: free_area_init: use maximal zone PFNs rather
than zone sizes) the initialization of the memory map relies on the
accuracy of memblock.memory to properly calculate zone sizes. The holes in
memblock.memory caused by absent regions reserved by the firmware cause
incorrect initialization of struct pages which leads to BUG() during the
initial page freeing:

BUG: Bad page state in process swapper  pfn:2ffc53
page:fffffc000ecf14c0 refcount:0 mapcount:1 mapping:0000000000000000 index:0x0
flags: 0x0()
raw: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
raw: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
page dumped because: nonzero mapcount
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 5.7.0-03841-gfa3354e4-dirty #26
       fffffc0001b5bd68 fffffc0001b5be80 fffffc00011cd148 fffffc000ecf14c0
       fffffc00019803df fffffc0001b5be80 fffffc00011ce340 fffffc000ecf14c0
       0000000000000000 fffffc0001b5be80 fffffc0001b482c0 fffffc00027d6618
       fffffc00027da7d0 00000000002ff97a 0000000000000000 fffffc0001b5be80
       fffffc00011d1abc fffffc000ecf14c0 fffffc0002d00000 fffffc0001b5be80
       fffffc0001b2350c 0000000000300000 fffffc0001b48298 fffffc0001b482c0
Trace:
[<fffffc00011cd148>] bad_page+0x168/0x1b0
[<fffffc00011ce340>] free_pcp_prepare+0x1e0/0x290
[<fffffc00011d1abc>] free_unref_page+0x2c/0xa0
[<fffffc00014ee5f0>] cmp_ex_sort+0x0/0x30
[<fffffc00014ee5f0>] cmp_ex_sort+0x0/0x30
[<fffffc000101001c>] _stext+0x1c/0x20

Fix this by registering the reserved ranges in memblock.memory.

Link: https://lore.kernel.org/lkml/20210726192311.uffqnanxw3ac5wwi@ivybridge
Fixes: fa3354e4 ("mm: free_area_init: use maximal zone PFNs rather than zone sizes")
Reported-by: Matt Turner <mattst88@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>

Merge tag 'drm-intel-fixes-2021-07-28' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes

Display related fixes:
- Fix vbt port mask
- Fix around reading the right DSC disable fuse in display_ver 10
- Split display version 9 and 10 in intel_setup_outputs
Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/YQF63ruuE72x2T45@intel.com

Short summary of fixes pull:

 * panel: Fix bpc for ytc700tlag_05_201c
 * ttm: debugfs init fixes
Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/YQFTESngqkeqzlhN@linux-uq9g.fritz.box

A few fixes for v5.14, including a fix for a crash if display triggers
an iommu fault (which tends to happen at probe time on devices with
bootloader fw that leaves display enabled as kernel starts)
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Rob Clark <robdclark@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/CAF6AEGubeV_uzWhsqp_+EmQmPcPatnqWOQnARoing2YvQOHbyg@mail.gmail.com

Pull ext2 and reiserfs fixes from Jan Kara:
 "A fix for the ext2 conversion to kmap_local() and two reiserfs
  hardening fixes"

* tag 'fixes_for_v5.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  reiserfs: check directory items on read from disk
  fs/ext2: Avoid page_address on pages returned by ext2_get_page
  reiserfs: add check for root_inode in reiserfs_fill_super

Merge tag 'platform-drivers-x86-v5.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86

Pull x86 platform driver fixes from Hans de Goede:
 "A set of bug-fixes and new hardware ids.

  Highlights:

   - amd-pmc fixes

   - think-lmi fixes

   - various new hardware-ids"

* tag 'platform-drivers-x86-v5.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86:
  platform/x86: gigabyte-wmi: add support for B550 Aorus Elite V2
  platform/x86: intel-hid: add Alder Lake ACPI device ID
  platform/x86: think-lmi: Fix possible mem-leaks on tlmi_analyze() error-exit
  platform/x86: think-lmi: Split kobject_init() and kobject_add() calls
  platform/x86: think-lmi: Move pending_reboot_attr to the attributes sysfs dir
  platform/x86: amd-pmc: Fix undefined reference to __udivdi3
  platform/x86: amd-pmc: Fix missing unlock on error in amd_pmc_send_cmd()
  platform/x86: wireless-hotkey: remove hardcoded "hp" from the error message
  platform/x86: amd-pmc: Use return code on suspend
  platform/x86: amd-pmc: Add new acpi id for future PMC controllers
  platform/x86: amd-pmc: Add support for ACPI ID AMDI0006
  platform/x86: amd-pmc: Add support for logging s0ix counters
  platform/x86: amd-pmc: Add support for logging SMU metrics
  platform/x86: amd-pmc: call dump registers only once
  platform/x86: amd-pmc: Fix SMU firmware reporting mechanism
  platform/x86: amd-pmc: Fix command completion code
  platform/x86: think-lmi: Add pending_reboot support

This file was given GPL-2.0 license. But LGPL-2.1 makes more sense
as it needs to be used by libraries outside of the kernel source tree.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

unix_gc() assumes that candidate sockets can never gain an external
reference (i.e.  be installed into an fd) while the unix_gc_lock is
held.  Except for MSG_PEEK this is guaranteed by modifying inflight
count under the unix_gc_lock.

MSG_PEEK does not touch any variable protected by unix_gc_lock (file
count is not), yet it needs to be serialized with garbage collection.
Do this by locking/unlocking unix_gc_lock:

 1) increment file count

 2) lock/unlock barrier to make sure incremented file count is visible
    to garbage collection

 3) install file into fd

This is a lock barrier (unlike smp_mb()) that ensures that garbage
collection is run completely before or completely after the barrier.

Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When removing a writeable device in __btrfs_free_extra_devids, the rw
device count should be decremented.

This error was caught by Syzbot which reported a warning in
close_fs_devices:

  WARNING: CPU: 1 PID: 9355 at fs/btrfs/volumes.c:1168 close_fs_devices+0x763/0x880 fs/btrfs/volumes.c:1168
  Modules linked in:
  CPU: 0 PID: 9355 Comm: syz-executor552 Not tainted 5.13.0-rc1-syzkaller #0
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
  RIP: 0010:close_fs_devices+0x763/0x880 fs/btrfs/volumes.c:1168
  RSP: 0018:ffffc9000333f2f0 EFLAGS: 00010293
  RAX: ffffffff8365f5c3 RBX: 0000000000000001 RCX: ffff888029afd4c0
  RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
  RBP: ffff88802846f508 R08: ffffffff8365f525 R09: ffffed100337d128
  R10: ffffed100337d128 R11: 0000000000000000 R12: dffffc0000000000
  R13: ffff888019be8868 R14: 1ffff1100337d10d R15: 1ffff1100337d10a
  FS:  00007f6f53828700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 000000000047c410 CR3: 00000000302a6000 CR4: 00000000001506f0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   btrfs_close_devices+0xc9/0x450 fs/btrfs/volumes.c:1180
   open_ctree+0x8e1/0x3968 fs/btrfs/disk-io.c:3693
   btrfs_fill_super fs/btrfs/super.c:1382 [inline]
   btrfs_mount_root+0xac5/0xc60 fs/btrfs/super.c:1749
   legacy_get_tree+0xea/0x180 fs/fs_context.c:592
   vfs_get_tree+0x86/0x270 fs/super.c:1498
   fc_mount fs/namespace.c:993 [inline]
   vfs_kern_mount+0xc9/0x160 fs/namespace.c:1023
   btrfs_mount+0x3d3/0xb50 fs/btrfs/super.c:1809
   legacy_get_tree+0xea/0x180 fs/fs_context.c:592
   vfs_get_tree+0x86/0x270 fs/super.c:1498
   do_new_mount fs/namespace.c:2905 [inline]
   path_mount+0x196f/0x2be0 fs/namespace.c:3235
   do_mount fs/namespace.c:3248 [inline]
   __do_sys_mount fs/namespace.c:3456 [inline]
   __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
   do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
   entry_SYSCALL_64_after_hwframe+0x44/0xae

Because fs_devices->rw_devices was not 0 after
closing all devices. Here is the call trace that was observed:

  btrfs_mount_root():
    btrfs_scan_one_device():
      device_list_add();   <---------------- device added
    btrfs_open_devices():
      open_fs_devices():
        btrfs_open_one_device();   <-------- writable device opened,
	                                     rw device count ++
    btrfs_fill_super():
      open_ctree():
        btrfs_free_extra_devids():
	  __btrfs_free_extra_devids();  <--- writable device removed,
	                              rw device count not decremented
	  fail_tree_roots:
	    btrfs_close_devices():
	      close_fs_devices();   <------- rw device count off by 1

As a note, prior to commit cf89af14 ("btrfs: dev-replace: fail
mount if we don't have replace item with target device"), rw_devices
was decremented on removing a writable device in
__btrfs_free_extra_devids only if the BTRFS_DEV_STATE_REPLACE_TGT bit
was not set for the device. However, this check does not need to be
reinstated as it is now redundant and incorrect.

In __btrfs_free_extra_devids, we skip removing the device if it is the
target for replacement. This is done by checking whether device->devid
== BTRFS_DEV_REPLACE_DEVID. Since BTRFS_DEV_STATE_REPLACE_TGT is set
only on the device with devid BTRFS_DEV_REPLACE_DEVID, no devices
should have the BTRFS_DEV_STATE_REPLACE_TGT bit set after the check,
and so it's redundant to test for that bit.

Additionally, following commit 82372bc8 ("Btrfs: make
the logic of source device removing more clear"), rw_devices is
incremented whenever a writeable device is added to the alloc
list (including the target device in btrfs_dev_replace_finishing), so
all removals of writable devices from the alloc list should also be
accompanied by a decrement to rw_devices.

Reported-by: syzbot+a70e2ad0879f160b9217@syzkaller.appspotmail.com
Fixes: cf89af14 ("btrfs: dev-replace: fail mount if we don't have replace item with target device")
CC: stable@vger.kernel.org # 5.10+
Tested-by: syzbot+a70e2ad0879f160b9217@syzkaller.appspotmail.com
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>

When checking if we need to log the new name of a renamed inode, we are
checking if the inode and its parent inode have been logged before, and if
not we don't log the new name. The check however is buggy, as it directly
compares the logged_trans field of the inodes versus the ID of the current
transaction. The problem is that logged_trans is a transient field, only
stored in memory and never persisted in the inode item, so if an inode
was logged before, evicted and reloaded, its logged_trans field is set to
a value of 0, meaning the check will return false and the new name of the
renamed inode is not logged. If the old parent directory was previously
fsynced and we deleted the logged directory entries corresponding to the
old name, we end up with a log that when replayed will delete the renamed
inode.

The following example triggers the problem:

  $ mkfs.btrfs -f /dev/sdc
  $ mount /dev/sdc /mnt

  $ mkdir /mnt/A
  $ mkdir /mnt/B
  $ echo -n "hello world" > /mnt/A/foo

  $ sync

  # Add some new file to A and fsync directory A.
  $ touch /mnt/A/bar
  $ xfs_io -c "fsync" /mnt/A

  # Now trigger inode eviction. We are only interested in triggering
  # eviction for the inode of directory A.
  $ echo 2 > /proc/sys/vm/drop_caches

  # Move foo from directory A to directory B.
  # This deletes the directory entries for foo in A from the log, and
  # does not add the new name for foo in directory B to the log, because
  # logged_trans of A is 0, which is less than the current transaction ID.
  $ mv /mnt/A/foo /mnt/B/foo

  # Now make an fsync to anything except A, B or any file inside them,
  # like for example create a file at the root directory and fsync this
  # new file. This syncs the log that contains all the changes done by
  # previous rename operation.
  $ touch /mnt/baz
  $ xfs_io -c "fsync" /mnt/baz

  <power fail>

  # Mount the filesystem and replay the log.
  $ mount /dev/sdc /mnt

  # Check the filesystem content.
  $ ls -1R /mnt
  /mnt/:
  A
  B
  baz

  /mnt/A:
  bar

  /mnt/B:
  $

  # File foo is gone, it's neither in A/ nor in B/.

Fix this by using the inode_logged() helper at btrfs_log_new_name(), which
safely checks if an inode was logged before in the current transaction.

A test case for fstests will follow soon.

CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

In compression write endio sequence, the range which the compressed_bio
writes is marked as uptodate if the last bio of the compressed (sub)bios
is completed successfully. There could be previous bio which may
have failed which is recorded in cb->errors.

Set the writeback range as uptodate only if cb->errors is zero, as opposed
to checking only the last bio's status.

Backporting notes: in all versions up to 4.4 the last argument is always
replaced by "!cb->errors".

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

For pure poll requests, it doesn't remove the second poll wait entry
when it's done, neither after vfs_poll() or in the poll completion
handler. We should remove the second poll wait entry.
And we use io_poll_remove_double() rather than io_poll_remove_waitqs()
since the latter has some redundant logic.

Fixes: 88e41cf9 ("io_uring: add multishot mode for IORING_OP_POLL_ADD")
Cc: stable@vger.kernel.org # 5.13+
Signed-off-by: Hao Xu <haoxu@linux.alibaba.com>
Link: https://lore.kernel.org/r/20210728030322.12307-1-haoxu@linux.alibaba.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

Some setups, like SCSI, can throw spurious -EAGAIN off the softirq
completion path. Normally we expect this to happen inline as part
of submission, but apparently SCSI has a weird corner case where it
can happen as part of normal completions.

This should be solved by having the -EAGAIN bubble back up the stack
as part of submission, but previous attempts at this failed and we're
not just quite there yet. Instead we currently use REQ_F_REISSUE to
handle this case.

For now, catch it in io_rw_should_reissue() and prevent a reissue
from a bogus path.

Cc: stable@vger.kernel.org
Reported-by: Fabian Ebner <f.ebner@proxmox.com>
Tested-by: Fabian Ebner <f.ebner@proxmox.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Reported as working here:
https://github.com/t-8ch/linux-gigabyte-wmi-driver/issues/1#issuecomment-879398883Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20210726153630.65213-1-linux@weissschuh.netSigned-off-by: Hans de Goede <hdegoede@redhat.com>