Commit Graph

2576 Commits

Author SHA1 Message Date
Takashi Iwai
546b928da0 ASoC: Fixes for v7.3
A relatively large pile of fixes here, a lot of driver specific stuff
 that's broadly unremarkable plus a few core fixes from Richard that fix
 issues where SoundWire systems with multiple CODECs on the same link
 would configure the CODECs to use the same bus slots leading to broken
 audio.
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Merge tag 'asoc-fix-v7.3-rc3' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v7.3

A relatively large pile of fixes here, a lot of driver specific stuff
that's broadly unremarkable plus a few core fixes from Richard that fix
issues where SoundWire systems with multiple CODECs on the same link
would configure the CODECs to use the same bus slots leading to broken
audio.
2026-09-17 08:15:32 +02:00
Nguyen Ngoc Thang
1e713f9bb2 ALSA: pcm: set timer->private_data before registering the PCM timer
snd_pcm_timer_init() calls snd_device_register() to link the new
struct snd_timer into the global timer list while it still carries
hw.c_resolution = snd_pcm_timer_resolution (and hw.start/hw.stop),
and only afterwards sets timer->private_data = substream.

Once the timer is on the list under register_mutex, a concurrent
reader can already reach it through the same mutex and invoke these
callbacks. /proc/asound/timers does this via c_resolution(), and
snd_timer_open()+snd_timer_start() reach start()/stop() the same way.
All three dereference timer->private_data, which for this brief
window is NULL, giving a NULL-pointer dereference:

  substream = timer->private_data;
  return substream->runtime ? ...   // substream is NULL

Move the private_data/private_free assignment before
snd_device_register() so the timer is never visible on the list
without its private_data set. On the snd_device_register() failure
path, private_free() (snd_pcm_timer_free()) can now run, but it only
does substream->timer = NULL, which is already NULL at that point
since substream->timer is set to the new timer just once, after a
successful registration -- so the failure path stays safe.

Reported-by: syzbot+19da64013c46df87f971@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=19da64013c46df87f971
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Nguyen Ngoc Thang <ngocthang2710.1999@gmail.com>
Link: https://patch.msgid.link/20260913134446.114724-1-ngocthang2710.1999@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-09-13 18:38:03 +02:00
Takashi Iwai
fd95e68df6 ALSA: core: Fix potential UAF after asynchronous card release
Usually a sound driver releases the resources assigned to the card via
snd_card_free(), and it synchronizes with the whole release procedure.
However, when the card is released asynchronously via
snd_card_free_when_closed() like USB-audio driver, the situation is
slightly different; although the snd_card_disconnect() call at the
disconnection guarantees that any newer accesses will be gated, the
in-flight tasks might be still accessing to the underlying card->dev
device even after the disconnection, which would cause a
use-after-free in the end, as reported by fuzzers.

For addressing the bug above, this patch takes the refcount of
card->dev at initialization of the card object, and releases at its
destructor.   This assures the availability of the card->dev in its
whole lifecycle.

Reported-by: Farhad Alemi <farhad.alemi@berkeley.edu>
Closes: https://lore.kernel.org/CA+0ovChexj4TrZL_2iG_P0WBEbZc5+73GfB3DkciQi=R8pZOnA@mail.gmail.com
Closes: https://lore.kernel.org/CA+0ovCgQUQNN=Z1tJTouiCsDaXR5M-3-SQEGk-cpPXQkM5Xh+w@mail.gmail.com
Cc: <stable@vger.kernel.org>
Link: https://patch.msgid.link/20260912162150.455144-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-09-13 09:07:08 +02:00
Kees Cook
3a2c4d55e3 treewide: refresh kmalloc_obj() conversions
This is another run of the Coccinelle script for converting kmalloc()
family of allocations to kmalloc_obj() via the existing rules in
scripts/coccinelle/api/kmalloc_objs.cocci

This catches both the set of kmalloc() uses added since the first
kmalloc_obj() conversions in v7.0 and adds a large group missed in the
first pass due to Coccinelle not interacting well with the cleanup.h
scoped_...() family of macros[1]. I worked around this with spatch's
"--macro-file" argument to a file with all the scoped_...() macros mapped
to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control
flow indicator I could find.

Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc,
riscv, and s390 with no new warnings.

Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1]
Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2]
Signed-off-by: Kees Cook <kees+treewide@kernel.org>
2026-09-04 21:37:00 -07:00
HyeongJun An
f4a23e17d8 ALSA: rawmidi: Return the error from snd_rawmidi_input_params()
The snd_rawmidi_input_params() computes err for the three invalid mode
combinations and for resize_runtime_buffer(), applies the new framing
and clock type only when err is zero, and then returns 0 anyway.  A
caller that asked for parameters the kernel rejected is told the change
succeeded, and the substream keeps its old buffer.

The open_mutex conversion turned the early returns into assignments.
It handled the output sibling correctly, which still returns err, and
left this one behind.

Fixes: 94b98194b6 ("ALSA: rawmidi: Take open_mutex around parameter changes")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-5
Signed-off-by: HyeongJun An <sammiee5311@gmail.com>
Link: https://patch.msgid.link/20260902125058.19499-1-sammiee5311@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-09-02 15:30:14 +02:00
Qingyu Zhang
adeee71876 ALSA: ump: do not touch legacy_rmidi before it exists
snd_ump_parse_endpoint() sets ump->parsed on every exit, including
error, before the caller attaches the legacy rawmidi device.
ump_handle_ep_name_msg() then treats parsed as "legacy_rmidi is live"
and calls ump_legacy_set_rawmidi_name(), which snprintf()s into
ump->legacy_rmidi->name. If a UMP packet arrives in that window
(IRQ path from snd_ump_receive), legacy_rmidi is still NULL
(KASAN null-ptr-deref in snprintf).

Guard the legacy helpers. parsed only means endpoint info was
parsed, not that legacy_rmidi exists.

Fixes: 37e0e14128 ("ALSA: ump: Support UMP Endpoint and Function Block parsing")
Signed-off-by: Qingyu Zhang <usupergate@gmail.com>
Link: https://patch.msgid.link/20260902073918.880245-1-usupergate@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-09-02 11:10:49 +02:00
Yilin Zhang
9b110a9dce ALSA: pcm: Serialize PCM mmap with buffer reallocation to fix page UAF
snd_pcm_hw_params() and snd_pcm_hw_free() guard buffer reallocation
with an mmap_count check performed under the PCM stream lock, but the
lock is released long before the buffer is actually freed:
snd_pcm_sync_stop(), constraint refinement and do_free_pages() all
happen in between.  snd_pcm_mmap_data(), on the other hand, takes no
lock at all: it validates against the old buffer's state and
dma_bytes, remaps its pages into the VMA, and only then increments
mmap_count.

A concurrent mmap() can therefore slip in between the check and the
free.  remap_pfn_range() installs writable PTEs for the old buffer's
pages without taking page references, and the subsequent
do_free_pages() returns those pages to the page allocator while the
VMA still maps them.  This leaves a stale, writable mapping of freed
pages: a page-level use-after-free that can be leveraged for local
privilege escalation.

Make snd_pcm_mmap_data() participate in the buffer-access scheme
introduced for hw_params/hw_free: acquire runtime->buffer_accessing
before validating and remapping, and release it afterwards.  Buffer
reallocation already fails with -EBUSY while accessors are active,
and the mmap side now fails with -EBUSY while a reallocation is in
progress, so the validate/remap sequence and the check/free sequence
can no longer interleave.

A reproducer that turns this race into a stale writable mapping of
the freed DMA buffer pages is available on request.

Reported-by: Kimi Security Team <bug-report@moonshot.ai>
Fixes: 92ee3c60ec ("ALSA: pcm: Fix races among concurrent hw_params and hw_free calls")
Signed-off-by: Yilin Zhang <yilinzhang@moonshot.ai>
Link: https://patch.msgid.link/20260831045506.889070-1-yilinzhang@moonshot.ai
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-08-31 10:10:15 +02:00
Takashi Iwai
acac7b5e07 ALSA: pcm: Fix race between non-atomic ops and trigger-start
We protect the races of the concurrent state transitions between
atomic PCM ops, but the checks between the non-atomic ops (hw_params,
hw_free and prepare) and the atomic ops aren't perfect; there is a
check of the conflicting PCM state at the beginning of hw_params & co,
but the atomic PCM ops can be still issued during the non-atomic PCM
operations.  An example such scenario is that a thread A re-issues the
PREPARE or HW_PARAMS for the already prepared stream, while another
thread B triggers the PCM start in the middle of the prepare
operation.  Although this usually doesn't lead to much serious issues,
it can give some inconsistency as reported by syzkaller (such as
ODEBUG warning).

There are various atomic PCM ops, and basically the only problem is
the PCM start as it operates from the PREPARED state.  Other trigger
commands (stop, etc) are for the running or the other special state,
hence they are filtered as pre-condition.

This patch is for preventing the PCM trigger-start during the non-
atomic operations in order to address the problems above.
Fortunately, the hw_params, hw_free and prepare operations call
snd_pcm_buffer_access_lock(), and this can be used for checking the
concurrent operations at the PCM trigger -- which sets the
runtime->buffer_accessing to a negative (if possible), so the PCM
trigger just needs to check the runtime->buffer_accessing value; if
it's negative, it means the concurrent non-atomic PCM ops is running.

Reported-by: syzbot+225231fce6755d40d078@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/6a8f0de8.1d9ded08.62e62.00b5.GAE@google.com
Cc: <stable@vger.kernel.org>
Link: https://patch.msgid.link/20260828115542.3999-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-08-31 10:06:16 +02:00
Linus Torvalds
c20313e98b sound fixes for 7.3-rc1
A collection of various small fixes since the last PR.
 Most changes are device-specific fixes, while there are a few fixes
 addressing the issues reported recently by fuzzers.
 
 Here are highlights:
 
 * ALSA Core:
 - Prevent adding invalid kcontrols to the LED layer
 - Workaround for a false-positive mutex lockdep warning in rawmidi
 
 * USB-audio:
 - Relaxed the sticky mixer behavior check that caused regressions
 - Fix an OOB write in Novation MIDI output
 - Proper cleanup after system-resume errors
 - Quirk updates for M-Audio Venom, Audient iD14 MkI, Logitech PRO X
   Wireless, SMSL USB DAC, and Creative Sound Blaster Play! 3
 
 HD-audio:
 - Conexant headset plugin fixes
 - Quirk additions and fixes for HP Laptop 15, Lenovo IdeaPad Slim 3,
   TongFang XxAF5xxx, Lenovo Legion Pro 7, and Lenovo Yoga Pro 9
 
 ASoC:
 - DAPM: Fix off-by-one check on the second enum channel
 - Tegra: Fix and sort register defaults
 - AMD quirk updates for ASUS FA401EA, HP OmniBook X Flip 16,
   HVY-WXX9/M1060, Alienware m18 R1, and MSI Thin A15 B7UC
 - Fixes Qualcomm TDM handling
 - Fix double put_device() on SoundWire
 - Codec fixes for rt766, tac5xx2, rt712, tas2783, and max98926
 
 Misc:
 - Fix card leak on probe error on ice1712 driver
 - Hardening for legacy aoa, mtpav and pcxhr drivers
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Merge tag 'sound-fix-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound

Pull sound fixes from Takashi Iwai:
 "A collection of various small fixes since the last PR. Most changes
  are device-specific fixes, while there are a few fixes addressing the
  issues reported recently by fuzzers.

  Here are highlights:

  ALSA Core:
   - Prevent adding invalid kcontrols to the LED layer
   - Workaround for a false-positive mutex lockdep warning in rawmidi

  USB-audio:
   - Relaxed the sticky mixer behavior check that caused regressions
   - Fix an OOB write in Novation MIDI output
   - Proper cleanup after system-resume errors
   - Quirk updates for M-Audio Venom, Audient iD14 MkI, Logitech PRO X
     Wireless, SMSL USB DAC, and Creative Sound Blaster Play! 3

  HD-audio:
   - Conexant headset plugin fixes
   - Quirk additions and fixes for HP Laptop 15, Lenovo IdeaPad Slim 3,
     TongFang XxAF5xxx, Lenovo Legion Pro 7, and Lenovo Yoga Pro 9

  ASoC:
   - DAPM: Fix off-by-one check on the second enum channel
   - Tegra: Fix and sort register defaults
   - AMD quirk updates for ASUS FA401EA, HP OmniBook X Flip 16,
     HVY-WXX9/M1060, Alienware m18 R1, and MSI Thin A15 B7UC
   - Fixes Qualcomm TDM handling
   - Fix double put_device() on SoundWire
   - Codec fixes for rt766, tac5xx2, rt712, tas2783, and max98926

  Misc:
   - Fix card leak on probe error on ice1712 driver
   - Hardening for legacy aoa, mtpav and pcxhr drivers"

* tag 'sound-fix-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (53 commits)
  ALSA: control: Don't add invalid kcontrols to LED layer
  ASoC: amd: acp-config: change quirks to cover all ASUS FA401EA variants
  ALSA: hda/conexant: Always enable the headset-mic pin on plugin
  ASoC: dapm: Fix off-by-one check on the second enum channel
  ASoC: amd: acp-config: force SoundWire probe on HP OmniBook X Flip 16
  ASoC: amd: acp3x-es83xx: Add HVY-WXX9/M1060 DMI quirk
  ASoC: amd: acp-config: Add HVY-WXX9/M1060 DMI quirk
  ASoC: soc-generic-dmaengine: Fix DMA channel request warning
  ALSA: rawmidi: Another workaround for false-positive mutex lockdep warning
  ASoC: amd: yc: Add DMI entry for Alienware m18 R1 AMD
  ASoC: amd: yc: Add DMI entry for MSI Thin A15 B7UC
  ALSA: hda/realtek: Fix speaker mute LED for HP Laptop 15-fd0039nt
  ALSA: usb-audio: Complete cleanup after system-resume errors
  ALSA: hda/realtek: Add quirk for Lenovo IdeaPad Slim 3 15ABR8
  ALSA: aoa: i2sbus: Check IRQ before requesting it
  ALSA: usb-audio: Skip mixer creation on M-Audio Venom
  ALSA: usb-audio: Skip reading sample rate on M-Audio Venom
  ASoC: rt766: add RT766/RT767 VA1 device IDs
  ALSA: hda/realtek: Add quirk for TongFang XxAF5xxx
  ALSA: usb-audio: fix OOB write in snd_usbmidi_novation_output()
  ...
2026-08-28 10:01:02 -07:00
Takashi Iwai
74e3b979ce ALSA: control: Don't add invalid kcontrols to LED layer
The kcontrol LED state layer tries to track the all associated
kcontrol elements with naive assumptions that they are readable.
But one can create a write-only element that has no get callback (even
a user element can do it), and this may lead to a NULL dereference at
the call chain of snd_ctl_led_notify(), as found by syzkaller.

For avoiding the Oops, add a sanity check of the kcontrol's info and
get callbacks, and just skip the invalid kcontrols before assigning
the kctl to the LED layer.

Reported-by: syzbot+b7fe2760ea6f1ee44b4d@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/6a9007b3.1d9ded08.62e62.00cd.GAE@google.com
Fixes: 22d8de62f1 ("ALSA: control - add generic LED trigger module as the new control layer")
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260827113951.893291-1-tiwai@suse.de
2026-08-27 16:15:08 +02:00
Takashi Iwai
58c1c30074 ALSA: rawmidi: Another workaround for false-positive mutex lockdep warning
While we attempted to work around the false-positive lockdep warning
due to the nested mutex lock in rawmidi at the open path for a UMP
legacy rawmidi, it didn't cover the similar locking at its close path,
and this still caused another false-positive reports by syzkaller.

Add a similar workaround to snd_rawmidi_kernel_release() as done in
the former commit 9c04742e73 ("ALSA: rawmidi: Work around
false-positive mutex lockdep warning") to cover completely.

Reported-by: syzbot+7d1edf0ff6a05961020c@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/6a8c7e4d.4d75e56a.c9a88.0052.GAE@google.com
Link: https://patch.msgid.link/20260825134942.1289272-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-08-25 15:55:37 +02:00
Linus Torvalds
ed3b875bea mm.git review status for mm-hotfixes-stable..mm-stable
Everything:
 
 Total patches:       501
 Reviews/patch:       1.66
 Reviewed rate:       70%
 
 Excluding DAMON:
 
 Total patches:       356
 Reviews/patch:       2.26
 Reviewed rate:       90%
 
 Excluding DAMON and selftests:
 
 Total patches:       329
 Reviews/patch:       2.31
 Reviewed rate:       92%
 
 Excluding DAMON, selftests and maple_tree:
 
 Total patches:       328
 Reviews/patch:       2.31
 Reviewed rate:       92%
 
 Summary of patch series in this merge:
 
 - The 2 patch series "mm: drop "sub" prefix from various places" from
   Dev Jain implements some page->folio conversion and a naming cleanup.
 
 - The 2 patch series "mm/kasan: remove redundant initialization for
   kasan_flag_write_only" from Igor Putko provides some KASAN cleanup work.
 
 - The 2 patch series "mm/filemap: reduce unnecessary xarray lookups"
   from Chi Zhiling provides a small speedup in the pagecaache read code.
 
 - The 4 patch series "mm/percpu: Fix possible NOFS/NOIO reclaim
   recursion" from Kaitao Cheng improves a few things in the vmalloc code -
   mainly the avoidance of GFP_KERNEL allocations when the caller asked for
   GFP_NOFS or GFP_NOIO.
 
 - The 3 patch series "mm/kmemleak: avoid soft lockup when scanning task
   stacks" from Breno Leitao avoids a soft lockup watchdog trigger from the
   kmemleak scanning code in extreme situations.
 
 - The 6 patch series "mm/page_owner: misc cleanups" from Ye Liu is a
   collection of unrelated cleanups to the page_owner code.  For some
   reason lots of people have been working on the page_owner code this
   cycle.
 
 - The 4 patch series "mm: convert to walk_page_range_vma() to eliminate
   find_vma()" from Kefeng Wang simplifies and accelerates the page walking
   library function.
 
 - The 3 patch series "mm/migrate: preparatory cleanups for batch copy
   and offload" from Shivank Garg implements cleanups in the migration
   code.
 
 - The 4 patch series "mm/page_owner: add per-fd filter infrastructure
   for print_mode and NUMA filtering" from Zhen Ni provides per-fd
   filtering to page_owner in order to reduce the sometimes vast amount of
   output it can produce.
 
 - The 19 patch series "mm: Refactor bootmem gigantic hugepage
   allocation" from Muchun Song is a "set of fixes and preparatory cleanups
   around bootmem HugeTLB handling, sparse initialization ordering, and
   related vmemmap setup".
 
 - The 4 patch series "mm/zsmalloc: reduce lock contention in zs_free()"
   from Wenchao Hao reduces lock contention in zs_free(), which dominates
   the unmap path under memory pressure on Android (LMK kills) and on x86
   servers running zswap-heavy workloads.  Up to 1.83x improvement in
   microbenchmarking.
 
 - The 2 patch series "move alloc_tag.c file under mm/" from Suren
   Baghdasaryan does that.
 
 - The 6 patch series "samples/damon: handle damon_{start,stop}()
   failures" from SJ Park fixes improper handling of damon_start(),
   damon_stop(), and damon_call() failures across DAMON sample modules to
   prevent potential memory leaks, operation disruptions and use-after-free
   bugs.
 
 - The 11 patch series "mm/damon/sysfs: kobject_del() directories that
   users can create/remove" from SJ Park resolves an issue where delayed
   sysfs directory removal under CONFIG_DEBUG_KOBJECT_RELEASE causes
   creation failures due to duplicate directory names by adding missing
   kobject_del() calls before creating new directories.
 
 - The 3 patch series "mm: cleanup clear_not_present_full_ptes()" from
   David Hildenbrand cleans up the core pte handling code.
 
 - The 3 patch series "selftests/damon: misc fixes for test bugs" from
   Kunwu Chan fixes several bugs in the DAMON selftests.
 
 - The 2 patch series "selftests/damon: fix memcg_path staging handling"
   from Cheng Nie fixes a bug in _damon_sysfs.py for damos_filter
   memcg_path setup, and adds a test case for it in sysfs.py.
 
 - The 2 patch series "selftests/damon: test kdamond refresh_ms" from
   Ruslan Valiyev introduces selftest coverage for DAMON's refresh_ms sysfs
   feature by updating the test control module and verifying that scheme
   stats update automatically without manual intervention.
 
 - The 5 patch series "mm/damon: five misc fixups" from Akinobu Mita
   contains miscellaneous DAMON fixups.
 
 - The 2 patch series "mm/damon/core: detect internal variation above
   max_nr_regions/2" from Jiayuan Chen fixes DAMON's region splitting
   behavior when region counts exceed half the maximum budget by
   dynamically scaling down the split fraction as the limit approaches,
   preventing large regions from staying un-split, and adds corresponding
   KUnit test coverage.
 
 - The 6 patch series "mm: preparatory patches for PMD level swap
   entries" from Usama Arif refactors and cleans up PMD softleaf helpers,
   call sites, and architecture flags to lay the groundwork for a follow-up
   series that introduces PMD page table swap entries.
 
 - The 11 patch series "mm/damon: update, optimize, and clean up doc,
   tests, and code" from SJ Park updates DAMON design and ABI
   documentation, expands unit and selftest coverage, optimizes
   damon_commit_target_regions(), and cleans up recently added sysfs
   interface code for better readability.
 
 - The 2 patch series "mm/vmpressure: reduce CPU, memory and code
   overhead on cgroup v2" from Usama Arif optimizes vmpressure() by
   skipping unnecessary work on cgroup v2 for userspace event notifications
   and refactors v1-only eventfd handling into mm/memcontrol-v1.c to reduce
   memory overhead and code complexity.
 
 - The 10 patch series "selftests/mm: refactor pkey helpers and fix mmap
   error handling" from Hongfu Li refactors pkeys shared tracing and
   assertion helpers into a common file, unifies protection key selftests
   to use consistent diagnostic logging and assertions, and enforces
   standardized MAP_FAILED return checks for mmap() calls across the tests.
 
 - The 18 patch series "mm/damon: optimize out nr_accesses_bp" from SJ
   Park replaces the error-prone, continuously updated nr_accesses_bp field
   in damon_region with an on-demand moving sum function
   (damon_nr_accesses_mvsum()), reducing structure memory overhead and
   avoiding state corruption bugs.
 
 - The 6 patch series "Open HugeTLB allocation routine for more generic
   use" from Ackerley Tng decouples HugeTLB folio allocation from VMA
   dependencies by introducing hugetlb_alloc_folio(), enabling subsystems
   like guest_memfd to allocate HugeTLB folios without standard VMA
   reservations or pseudo-VMAs.
 
 - The 3 patch series "mm/damon: provide pseudo moving sum probe_hits"
   from SJ Park integrates DAMON's probe_hits attribute counter into the
   pseudo moving sum infrastructure, enabling real-time, online monitoring
   without waiting for full aggregation intervals.
 
 - The 18 patch series "mm: Some cleanups for page allocator APIs" from
   Brendan Jackman simplifies and refactors the page allocator entry points
   and flags by unifying allocation paths, adding internal alloc_flags
   arguments, and eliminating redundant __ prefixed alloc_pages variants.
 
 - The 5 patch series "Fix incorrect access of hugetlb pte entries" from
   Dev Jain enforces the consistent use of huge_ptep_get() instead of
   ptep_get() for HugeTLB entries and fixes an unaligned address issue in
   arm64's huge_ptep_get() implementation.
 
 - The 8 patch series "mm/damon: validate all parameters in the core"
   from SJ Park consolidates parameter validation into the DAMON core
   specifically within damon_start() and damon_commit_ctx() to centralize
   error checking, eliminate caller-side redundant checks and to improve
   maintenance efficiency.
 
 - The 3 patch series "tools/mm/page_owner_sort: fix filtering and
   cleanup issues" from Yichong Chen renames is_need() to filter_record()
   for clearer return semantics, fixes per-record allocation memory leaks
   and bounds output copies in search_pattern() to address an existing
   buffer issue.
 
 - The 4 patch series "memcg: bail out reclaim when memcg is dying" from
   Jiayuan Chen mitigates a system-wide stall which occurs when a cgroup is
   removed while one of its memory control files is doing synchronous
   reclaim.
 
 - The 5 patch series "mm/memory-failure: add panic option for
   unrecoverable pages" from Breno Leitao introduces an opt-in
   vm.panic_on_unrecoverable_memory_failure sysctl that immediately panics
   the kernel on unrecoverable memory errors in kernel-owned pages to
   preserve error context and prevent delayed, silent data corruption.
 
 - The 11 patch series "mm/damon: refactor damon_{start,stop,commit}()
   for simple error handling" from SJ Park refactors the DAMON core API
   functions to guarantee that all contexts are fully stopped when
   damon_start(), damon_stop(), or damon_commit() fail, eliminating the
   need for complex and error-prone caller-side cleanup code.
 
 - The 5 patch series "Keep tail page private zero at free and folio
   split" from Zi Yan adds checks to ensure tail_page->private is zero when
   freeing compound or high-order pages and when promoting tail pages
   during large folio splits.  By validating these fields at free and split
   time, it allows the removal of redundant private field clearing inside
   prep_compound_tail().
 
 - The 4 patch series "mm: drop redundant lru_add_drain in anon folio
   reuse paths" from Barry Song eliminates redundant lru_add_drain() calls
   in wp_can_reuse_anon_folio() and do_swap_page() to reduce LRU lock
   contention and system overhead.
 
   By validating folio refcounts against the LRU cache before draining
   and removing unnecessary drains in the swap path, it achieves up to a
   30.5% reduction in drain calls during heavy swap workloads.
 
 - The 3 patch series "mm: clean up folio LRU and swap declarations" from
   Jianyue Wu reorganizes folio LRU and swap code by relocating
   page-cluster state to mm/swap_state.c, renaming mm/swap.c to mm/folio.c,
   and moving MM-internal reclaim declarations into mm/internal.h.
 
 - The 15 patch series "userfaultfd: working set tracking for VM guest
   memory" from Kiryl Shutsemau adds userfaultfd support for tracking the
   working set of VM guest memory, so a VMM can identify hot pages and
   reclaim cold ones to tiered or remote storage.
 
 - The 10 patch series "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part
   2)" from David Hildenbrand removes the remaining pieces of
   CONFIG_HAVE_BOOTMEM_INFO_NODE, performing some smaller cleanups around
   freeing of reserved vmemmap pages on the way.
 
 - The 7 patch series "mm/damon: update probe hits for runtime parameter
   commits" from SJ Park ensures that DAMON's probe_hits attribute counter
   is properly updated when monitoring intervals are changed at runtime,
   matching the behavior of nr_accesses.  To achieve this, it refactors and
   renames existing helper functions for shared use, applies the updates to
   probe_hits, and handles edge cases in damon_probe_hits_mvsum() to
   maintain measurement accuracy.
 
 - The 3 patch series "KSM: performance optimizations for rmap_walk_ksm"
   from xu xin resolves a severe KSM reverse-mapping performance bottleneck
   where thousands of split VMAs sharing a single anon_vma cause extended
   lock contention.  By adding an interval-filtering check during the rmap
   walk, it reduces worst-case anon_vma lock hold times from over 500ms
   down to under 2ms, preventing application freezes and latency spikes
   under memory pressure.
 
 - The 3 patch series "mm: split a couple of headers from internal.h"
   from Mike Rapoport splits declarations related to mm_init, memblock,
   vmalloc and sparse into new headers.
 
 - The 2 patch series "KSM: use linear_page_index in collect_procs_ksm()"
   from xu xin applies the interval tree optimization from rmap_walk_ksm()
   to collect_procs_ksm() to avoid iterating over non-matching VMAs during
   KSM memory error handling.  It hoists loop-invariant address
   initialization and restricts the anon_vma_interval_tree_foreach walk to
   a targeted page offset range, reducing redundant checks and improving
   lookup efficiency.
 
 - The 3 patch series "selftests/mm: avoid false failures in hugetlb and
   KSM tests" from Sayali Patil fixes issues in the hugetlb and KSM MM
   selftest categories that can report failures when the prerequisites for
   the tests are not satisfied.
 
 - The 19 patch series "mm/damon: introduce data attributes only
   monitoring" from SJ Park introduces attribute-weighted region management
   in DAMON, allowing users to prioritize specific data attributes (such as
   page sizes or cgroups) over or instead of access monitoring.
 
   By assigning weights to attribute probes, DAMON can completely disable
   access tracking and adjust monitoring regions based on weighted
   probe-hit counters to optimize monitoring quality for attribute-focused
   workloads.
 
 - The 8 patch series "mm/hmm: Add mmap lock-drop support for
   userfaultfd-backed mappings" from Stanislav Kinsburskii extends
   hmm_range_fault() to support userfaultfd-backed regions by allowing the
   mmap lock to be dropped during fault handling via a new
   hmm_range_fault_locked() helper.
 
   By accepting a locked pointer and signaling retry status when lock
   release occurs, it enables page fault resolution in userfaultfd regions
   while preserving backward compatibility for existing callers.
 
 - The 33 patch series "mm: make VMA page offset handling more
   consistent" from Lorenzo Stoakes cleans up and standardizes how
   vma->vm_pgoff is accessed and manipulated across file-backed and
   anonymous mappings in the kernel.
 
   It introduces dedicated helper functions such as vma_start_pgoff(),
   vma_end_pgoff(), vma_set_pgoff() and linear_page_delta() while renaming
   rmap interval tree helpers to better reflect their functionality.
 
   These changes establish a cleaner foundation for future work that will
   unify virtual page offset indexing for all anonymous and CoW'd folios.
 
 - The 3 patch series "mm: handle device-private PMDs in walk callbacks"
   from Usama Arif addresses kernel panics and state corruption caused by
   MM walk callbacks reaching non-present device-private PMD swap entries
   created during HMM migrations.
 
   It ensures that functions which acquire pmd_trans_huge_lock() properly
   recognize device-private PMDs instead of assuming a present THP or a
   standard migration entry.
 
 - The 5 patch series "mm/rmap: Refactor try_to_unmap_one" from Dev Jain
   refactors try_to_unmap_one by modularizing Hugetlb, anonymous-lazyfree,
   and anonymous-swapbacked logic into dedicated functions, laying the
   structural groundwork for batched anonymous large folio unmapping.
 
 - The 4 patch series "Docs/ABI/damon: sysfs ABI document fixes and
   additions" from Song Hu fixes typos and fills in missing entries in the
   DAMON sysfs ABI document.
 
 - The 10 patch series "dax/kmem: atomic whole-device hotplug via sysfs"
   from Gregory Price introduces an atomic sysfs state attribute and
   supporting DAX/MM infrastructure to prevent userland races when
   offlining and removing entire memory regions.
 
   By adding an unplugged state alongside standard online modes, it
   enables whole-device atomic hotplug control while preserving backward
   compatibility.
 
 - The 13 patch series "mm: convert more vm_flags_t users to vma_flags_t"
   from Lorenzo Stoakes continues transitioning the kernel from the
   deprecated vm_flags_t type to vma_flags_t across core memory management
   infrastructure.
 
   It replaces legacy type usage in core functions such as do_mmap(),
   unmapped area allocation, mm->def_vma_flags, and VMA operations like
   mlock, mprotect, and mremap.
 
 - The 2 patch series "Two small patches to clean up mm/mm_slot.h" from
   xu xin refactors mm_slot.h by introducing mm_slot_remove() to unify
   duplicate slot deletion sequences in khugepaged and KSM.  It also adds
   code documentation explaining why mm_slot_lookup and mm_slot_insert must
   remain as preprocessor macros rather than static inline functions.
 
 - The 10 patch series "mm/damon/core: hide core-private struct fields"
   from SJ Park cleans up DAMON core structures by consistently marking
   internal-only fields with private: comment tags to prevent improper
   direct access from outer layers.
 
   It enforces encapsulation across core structures including
   damon_region, damon_target, and damon_ctx and updates DAMON_SYSFS to
   interact through approved access APIs instead of exposing raw struct
   members.
 
 - The 6 patch series "mm/damon: unurgent fixes for infinite loop, NULL
   de-ref and races" from SJ Park addresses potential infinite loops, NULL
   dereferences, and race conditions identified in DAMON.
 
   It fixes an infinite loop triggered by extreme user configurations, a
   NULL pointer dereference within unit tests and minor monitoring
   accuracy degradation caused by subtle runtime races.
 
 - The 2 patch series "mm/page_alloc: fixes for free_pages_nolock() on
   RT/UP" from Brendan Jackman fixes an NMI safety flaw in
   __free_frozen_pages() where freeing pages on non-SMP or PREEMPT_RT
   kernels can bypass can_spin_trylock() checks via non-PCP or isolated
   migration paths.
 
   It also resolves potential kernel crashes and privilege escalation
   risks triggered when BPF tracing runs in NMI context alongside memory
   hotplug or large allocation frees.
 
 - The 4 patch series "mm/page_alloc: couple of followups for recent
   cleanups" from Brendan Jackman cleans up and updates page allocator
   nomenclature, documentation, and debug assertions.
 
   It aligns internal FPI_ flags with the public "nolock" naming
   convention, removes outdated internal implementation details from
   high-level page allocator comments, and eliminates obsolete VM_BUG_ON()
   assertions in allocation paths.
 
 - The 3 patch series "mm/mseal: further cleanups" from Lorenzo Stoakes
   refactors and simplifies the mseal implementation by clarifying API
   boundaries and removing unnecessary code complexity.
 
   It replaces generic do_mseal() usage outside the syscall with a
   dedicated mseal_mmap_page_zero() helper for MMAP_PAGE_ZERO, eliminates
   mm_struct parameters to enforce that sealing applies only to
   current->mm, and streamlines overall logic and comments with no
   functional changes intended.
 
 - The 4 patch series "mm/vmscan: fix swappiness=max and clean up
   per-node proactive reclaim" from Ridong Chen resolves reclaim behavior
   bugs and cleans up function parameters across memory reclaim paths.
 
   It fixes swappiness=max in both standard reclaim and MGLRU so
   unswappable anonymous memory no longer falls back to evicting page
   cache, ensures reclaim_store() returns accurate error codes instead of
   collapsing all failures into -EAGAIN, and removes the obsolete gfp_mask
   parameter from __node_reclaim().
 
 - The 6 patch series "mm: mincore: misc cleanups" from Kefeng Wang
   cleans up and simplifies the mincore code.  Most importantly, it removes
   the historical special behavior that always reports VM_PFNMAP pages as
   non-resident.
 
 - The 2 patch series "mm/huge_memory: drop dead split helper variants"
   from Kiryl Shutsemau implements two trivial cleanups in the folio split
   API.
 
 - The 7 patch series "mm/damon: fix uninitialized DAMOS field and kunit
   exec expectation bugs" from SJ Park resolves minor operational and
   testing bugs in DAMON identified by Sashiko.  It initializes the
   damos->last_applied field to prevent occasional efficiency degradation
   and fixes invalid memory accesses in DAMON KUnit tests during test
   failure handling.
 
 - The 3 patch series "cleanup for stable_page_flags()" from Jinjiang Tu
   cleans up and refactors stable_page_flags() used by /proc/kpageflags
   without altering functionality.
 
   It uses BIT_ULL() to prevent shift-overflow warnings on 64-bit flag
   bits, converts folio-specific flag checks to standard folio_test_*()
   helpers, and removes redundant CONFIG_PAGE_IDLE_FLAG handling.
 
 - The 3 patch series "Batch unmap of uffd-wp file folios" from Dev Jain
   extends batched folio unmapping support to file folios within
   userfaultfd write-protect (uffd-wp) VMAs by adding batching capabilities
   to pte_install_uffd_wp_if_needed().
 
   This removes special-case restrictions on uffd-wp VMAs in
   try_to_unmap_one(), significantly simplifying the function's control
   flow and complexity.
 
 - The 3 patch series "mm/early_ioremap: clarify and clean up
   early_ioremap_reset()" from Sang-Heon Jeon clarifies and cleans up the
   architecture-specific usage of __late_set_fixmap() and
   __late_clear_fixmap() after early_ioremap_reset().
 
   It adds explicit documentation regarding when early_ioremap_reset()
   must be called and removes redundant macro definitions and reset calls
   in the RISC-V and ARM64 architectures.
 
 - The 4 patch series "mm: fix reclaim storms in defrag_mode" from
   Johannes Weiner addresses severe performance regressions, swap storms,
   and spurious OOMs caused by vm.defrag_mode=1 under high memory pressure
   in Meta production.
 
   It updates the page allocator slowpath so non-movable allocation
   requests actively trigger direct reclaim and direct compaction at
   pageblock_order scale, allowing them to claim whole pageblocks rather
   than spinning unproductively.
 
 - The 2 patch series "zram: lockmap tweaks" from Sebastian Siewior
   optimizes and fixes lockdep tracking for zram devices by consolidating
   per-entry lockmaps and isolating lock classes across multiple instances.
 
   It reduces memory overhead by replacing per-entry lockdep_map instances
   with a single map per struct zram, and assigns a dynamic lock_class_key
   to each instance to prevent false deadlock reports when different zram
   devices are backed by distinct filesystems.
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Merge tag 'mm-stable-2026-08-18-18-39' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - "mm: drop "sub" prefix from various places" (Dev Jain)

   page->folio conversion and a naming cleanup

 - "mm/kasan: remove redundant initialization for kasan_flag_write_only"
   (Igor Putko)

   KASAN cleanup work

 - "mm/filemap: reduce unnecessary xarray lookups" (Chi Zhiling)

   Small speedup in the pagecaache read code

 - "mm/percpu: Fix possible NOFS/NOIO reclaim recursion" (Kaitao Cheng)

   Improve the vmalloc code - mainly the avoidance of GFP_KERNEL
   allocations when the caller asked for GFP_NOFS or GFP_NOIO

 - "mm/kmemleak: avoid soft lockup when scanning task stacks" (Breno
   Leitao)

   Avoid a soft lockup watchdog trigger from the kmemleak scanning code
   in extreme situations

 - "mm/page_owner: misc cleanups" (Ye Liu)

   Cleanups to the page_owner code. For some reason lots of people have
   been working on the page_owner code this cycle.

 - "mm: convert to walk_page_range_vma() to eliminate find_vma()"
   (Kefeng Wang)

   Simplify and accelerate the page walking library function

 - "mm/migrate: preparatory cleanups for batch copy and offload"
   (Shivank Garg)

   Cleanups in the migration code

 - "mm/page_owner: add per-fd filter infrastructure for print_mode and
   NUMA filtering" (Zhen Ni)

   Per-fd filtering to page_owner in order to reduce the sometimes vast
   amount of output it can produce

 - "mm: Refactor bootmem gigantic hugepage allocation" (Muchun Song)

   Fixes and preparatory cleanups around bootmem HugeTLB handling,
   sparse initialization ordering, and related vmemmap setup

 - "mm/zsmalloc: reduce lock contention in zs_free()" (Wenchao Hao)

   Reduce lock contention in zs_free(), which dominates the unmap path
   under memory pressure on Android (LMK kills) and on x86 servers
   running zswap-heavy workloads.

   Up to 1.83x improvement in microbenchmarking.

 - "move alloc_tag.c file under mm/" (Suren Baghdasaryan)

 - "samples/damon: handle damon_{start,stop}() failures" (SJ Park)

   Fix improper handling of damon_start(), damon_stop(), and
   damon_call() failures across DAMON sample modules to prevent
   potential memory leaks, operation disruptions and use-after-free
   bugs

 - "mm/damon/sysfs: kobject_del() directories that users can
   create/remove" (SJ Park)

   Fix delayed sysfs directory removal under DEBUG_KOBJECT_RELEASE
   causeing creation failures due to duplicate directory names by adding
   missing kobject_del() calls before creating new directories

 - "mm: cleanup clear_not_present_full_ptes()" (David Hildenbrand)

   Clean up the core pte handling code

 - "selftests/damon: misc fixes for test bugs" (Kunwu Chan)

   Fix several bugs in the DAMON selftests

 - "selftests/damon: fix memcg_path staging handling" (Cheng Nie)

   Fix a bug in _damon_sysfs.py for damos_filter memcg_path setup, and
   add a test case for it in sysfs.py.

 - "selftests/damon: test kdamond refresh_ms" (Ruslan Valiyev)

   Selftest coverage for DAMON's refresh_ms sysfs feature by updating
   the test control module and verifying that scheme stats update
   automatically without manual intervention

 - "mm/damon: five misc fixups" (Akinobu Mita)

   Miscellaneous DAMON fixups.

 - "mm/damon/core: detect internal variation above max_nr_regions/2"
   (Jiayuan Chen)

   Fix DAMON's region splitting behavior when region counts exceed half
   the maximum budget by dynamically scaling down the split fraction as
   the limit approaches, preventing large regions from staying un-split,
   and add corresponding KUnit test coverage

 - "mm: preparatory patches for PMD level swap entries" (Usama Arif)

   Refactor and clean up PMD softleaf helpers, call sites, and
   architecture flags to lay the groundwork for a follow-up series that
   introduces PMD page table swap entries

 - "mm/damon: update, optimize, and clean up doc, tests, and code" (SJ
   Park)

   Update DAMON design and ABI documentation, expands unit and selftest
   coverage, optimize damon_commit_target_regions(), and clean up
   recently added sysfs interface code for better readability

 - "mm/vmpressure: reduce CPU, memory and code overhead on cgroup v2"
   (Usama Arif)

   Optimize vmpressure() by skipping unnecessary work on cgroup v2 for
   userspace event notifications and refactor v1-only eventfd handling
   into mm/memcontrol-v1.c to reduce memory overhead and code complexity

 - "selftests/mm: refactor pkey helpers and fix mmap error handling"
   (Hongfu Li)

   Refactor pkeys shared tracing and assertion helpers into a common
   file, unify protection key selftests to use consistent diagnostic
   logging and assertions, and enforce standardized MAP_FAILED return
   checks for mmap() calls across the tests

 - "mm/damon: optimize out nr_accesses_bp" (SJ Park)

   Replace the error-prone, continuously updated nr_accesses_bp field in
   damon_region with an on-demand moving sum function, reducing
   structure memory overhead and avoiding state corruption bugs

 - "Open HugeTLB allocation routine for more generic use" (Ackerley Tng)

   Decouple HugeTLB folio allocation from VMA dependencies by
   introducing hugetlb_alloc_folio(), enabling subsystems like
   guest_memfd to allocate HugeTLB folios without standard VMA
   reservations or pseudo-VMAs

 - "mm/damon: provide pseudo moving sum probe_hits" (SJ Park)

   Integrate DAMON's probe_hits attribute counter into the pseudo moving
   sum infrastructure, enabling real-time, online monitoring without
   waiting for full aggregation intervals

 - "mm: Some cleanups for page allocator APIs" (Brendan Jackman)

   Simplify and refactor the page allocator entry points and flags by
   unifying allocation paths, adding internal alloc_flags arguments, and
   eliminating redundant __ prefixed alloc_pages variants.

 - "Fix incorrect access of hugetlb pte entries" (Dev Jain)

   Enforce the consistent use of huge_ptep_get() instead of ptep_get()
   for HugeTLB entries and fixes an unaligned address issue in arm64's
   huge_ptep_get() implementation

 - "mm/damon: validate all parameters in the core" (SJ Park)

   Consolidate parameter validation into the DAMON core specifically
   within damon_start() and damon_commit_ctx() to centralize error
   checking, eliminate caller-side redundant checks and to improve
   maintenance efficiency

 - "tools/mm/page_owner_sort: fix filtering and cleanup issues" (Yichong
   Chen)

   Rename is_need() to filter_record() for clearer return semantics, fix
   per-record allocation memory leaks and bound output copies in
   search_pattern() to address an existing buffer issue

 - "memcg: bail out reclaim when memcg is dying" (Jiayuan Chen)

   Mitigate a system-wide stall which occurs when a cgroup is removed
   while one of its memory control files is doing synchronous reclaim

 - "mm/memory-failure: add panic option for unrecoverable pages" (Breno
   Leitao)

   Introduce an opt-in vm.panic_on_unrecoverable_memory_failure sysctl
   that immediately panics the kernel on unrecoverable memory errors in
   kernel-owned pages to preserve error context and prevent delayed,
   silent data corruption

 - "mm/damon: refactor damon_{start,stop,commit}() for simple error
   handling" (SJ Park)

   Refactor the DAMON core API functions to guarantee that all contexts
   are fully stopped when damon_start(), damon_stop(), or damon_commit()
   fail, eliminating the need for complex and error-prone caller-side
   cleanup code

 - "Keep tail page private zero at free and folio split" (Zi Yan)

   Add checks to ensure tail_page->private is zero when freeing compound
   or high-order pages and when promoting tail pages during large folio
   splits. By validating these fields at free and split time, it allows
   the removal of redundant private field clearing inside
   prep_compound_tail()

 - "mm: drop redundant lru_add_drain in anon folio reuse paths" (Barry
   Song)

   Eliminate redundant lru_add_drain() calls in
   wp_can_reuse_anon_folio() and do_swap_page() to reduce LRU lock
   contention and system overhead

   By validating folio refcounts against the LRU cache before draining
   and removing unnecessary drains in the swap path, it achieves up to a
   30.5% reduction in drain calls during heavy swap workloads

 - "mm: clean up folio LRU and swap declarations" (Jianyue Wu)

   Reorganize folio LRU and swap code by relocating page-cluster state
   to mm/swap_state.c, renaming mm/swap.c to mm/folio.c, and moving
   MM-internal reclaim declarations into mm/internal.h.

 - "userfaultfd: working set tracking for VM guest memory" (Kiryl
   Shutsemau)

   Add userfaultfd support for tracking the working set of VM guest
   memory, so a VMM can identify hot pages and reclaim cold ones to
   tiered or remote storage

 - "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part 2)" (David
   Hildenbrand)

   Remove the remaining pieces of CONFIG_HAVE_BOOTMEM_INFO_NODE,
   performing some smaller cleanups around freeing of reserved vmemmap
   pages on the way.

 - "mm/damon: update probe hits for runtime parameter commits" (SJ Park)

   Ensure that DAMON's probe_hits attribute counter is properly updated
   when monitoring intervals are changed at runtime, matching the
   behavior of nr_accesses. To achieve this, it refactors and renames
   existing helper functions for shared use, applies the updates to
   probe_hits, and handles edge cases in damon_probe_hits_mvsum() to
   maintain measurement accuracy.

 - "KSM: performance optimizations for rmap_walk_ksm" (xu xin)

   Resolve a severe KSM reverse-mapping performance bottleneck where
   thousands of split VMAs sharing a single anon_vma cause extended lock
   contention.

   By adding an interval-filtering check during the rmap walk, it
   reduces worst-case anon_vma lock hold times from over 500ms down to
   under 2ms, preventing application freezes and latency spikes under
   memory pressure.

 - "mm: split a couple of headers from internal.h" (Mike Rapoport)

   Split declarations related to mm_init, memblock, vmalloc and sparse
   into new headers

 - "KSM: use linear_page_index in collect_procs_ksm()" (xu xin)

   Apply the interval tree optimization from rmap_walk_ksm() to
   collect_procs_ksm() to avoid iterating over non-matching VMAs during
   KSM memory error handling.

   It hoists loop-invariant address initialization and restricts the
   anon_vma_interval_tree_foreach walk to a targeted page offset range,
   reducing redundant checks and improving lookup efficiency.

 - "selftests/mm: avoid false failures in hugetlb and KSM tests" (Sayali
   Patil)

   Fix issues in the hugetlb and KSM MM selftest categories that can
   report failures when the prerequisites for the tests are not
   satisfied

 - "mm/damon: introduce data attributes only monitoring" (SJ Park)

   Introduce attribute-weighted region management in DAMON, allowing
   users to prioritize specific data attributes (such as page sizes or
   cgroups) over or instead of access monitoring.

   By assigning weights to attribute probes, DAMON can completely
   disable access tracking and adjust monitoring regions based on
   weighted probe-hit counters to optimize monitoring quality for
   attribute-focused workloads.

 - "mm/hmm: Add mmap lock-drop support for userfaultfd-backed mappings"
   (Stanislav Kinsburskii)

   Extend hmm_range_fault() to support userfaultfd-backed regions by
   allowing the mmap lock to be dropped during fault handling via a new
   hmm_range_fault_locked() helper.

   By accepting a locked pointer and signaling retry status when lock
   release occurs, it enables page fault resolution in userfaultfd
   regions while preserving backward compatibility for existing callers.

 - "mm: make VMA page offset handling more consistent" (Lorenzo Stoakes)

   Clean up and standardize how vma->vm_pgoff is accessed and
   manipulated across file-backed and anonymous mappings in the kernel

   It introduces dedicated helper functions such as vma_start_pgoff(),
   vma_end_pgoff(), vma_set_pgoff() and linear_page_delta() while
   renaming rmap interval tree helpers to better reflect their
   functionality.

   These changes establish a cleaner foundation for future work that
   will unify virtual page offset indexing for all anonymous and CoW'd
   folios.

 - "mm: handle device-private PMDs in walk callbacks" (Usama Arif)

   Address kernel panics and state corruption caused by MM walk
   callbacks reaching non-present device-private PMD swap entries
   created during HMM migrations

   It ensures that functions which acquire pmd_trans_huge_lock()
   properly recognize device-private PMDs instead of assuming a present
   THP or a standard migration entry.

 - "mm/rmap: Refactor try_to_unmap_one" (Dev Jain)

   Refactor try_to_unmap_one by modularizing Hugetlb,
   anonymous-lazyfree, and anonymous-swapbacked logic into dedicated
   functions, laying the structural groundwork for batched anonymous
   large folio unmapping.

 - "Docs/ABI/damon: sysfs ABI document fixes and additions" (Song Hu)

   Fix typos and fills in missing entries in the DAMON sysfs ABI
   document

 - "dax/kmem: atomic whole-device hotplug via sysfs" (Gregory Price)

   Introduce an atomic sysfs state attribute and supporting DAX/MM
   infrastructure to prevent userland races when offlining and removing
   entire memory regions

   By adding an unplugged state alongside standard online modes, it
   enables whole-device atomic hotplug control while preserving backward
   compatibility.

 - "mm: convert more vm_flags_t users to vma_flags_t" (Lorenzo Stoakes)

   Continue transitioning the kernel from the deprecated vm_flags_t type
   to vma_flags_t across core memory management infrastructure.

   It replaces legacy type usage in core functions such as do_mmap(),
   unmapped area allocation, mm->def_vma_flags, and VMA operations like
   mlock, mprotect, and mremap.

 - "Two small patches to clean up mm/mm_slot.h" (xu xin)

   Refactor mm_slot.h by introducing mm_slot_remove() to unify duplicate
   slot deletion sequences in khugepaged and KSM. It also adds code
   documentation explaining why mm_slot_lookup and mm_slot_insert must
   remain as preprocessor macros rather than static inline functions.

 - "mm/damon/core: hide core-private struct fields" (SJ Park)

   Clean up DAMON core structures by consistently marking internal-only
   fields with private: comment tags to prevent improper direct access
   from outer layers.

   It enforces encapsulation across core structures including
   damon_region, damon_target, and damon_ctx and updates DAMON_SYSFS to
   interact through approved access APIs instead of exposing raw struct
   members.

 - "mm/damon: unurgent fixes for infinite loop, NULL de-ref and races"
   (SJ Park)

   Address potential infinite loops, NULL dereferences, and race
   conditions identified in DAMON

   It fixes an infinite loop triggered by extreme user configurations, a
   NULL pointer dereference within unit tests and minor monitoring
   accuracy degradation caused by subtle runtime races.

 - "mm/page_alloc: fixes for free_pages_nolock() on RT/UP" (Brendan
   Jackman)

   Fix an NMI safety flaw in __free_frozen_pages() where freeing pages
   on non-SMP or PREEMPT_RT kernels can bypass can_spin_trylock() checks
   via non-PCP or isolated migration paths.

   It also resolves potential kernel crashes and privilege escalation
   risks triggered when BPF tracing runs in NMI context alongside memory
   hotplug or large allocation frees.

 - "mm/page_alloc: couple of followups for recent cleanups" (Brendan
   Jackman)

   Clean up and update page allocator nomenclature, documentation, and
   debug assertions.

   It aligns internal FPI_ flags with the public "nolock" naming
   convention, removes outdated internal implementation details from
   high-level page allocator comments, and eliminates obsolete
   VM_BUG_ON() assertions in allocation paths.

 - "mm/mseal: further cleanups" (Lorenzo Stoakes)

   Refactor and simplify the mseal implementation by clarifying API
   boundaries and removing unnecessary code complexity.

   It replaces generic do_mseal() usage outside the syscall with a
   dedicated mseal_mmap_page_zero() helper for MMAP_PAGE_ZERO,
   eliminates mm_struct parameters to enforce that sealing applies only
   to current->mm, and streamlines overall logic and comments with no
   functional changes intended.

 - "mm/vmscan: fix swappiness=max and clean up per-node proactive
   reclaim" (Ridong Chen)

   Resolve reclaim behavior bugs and clean up function parameters across
   memory reclaim paths

   It fixes swappiness=max in both standard reclaim and MGLRU so
   unswappable anonymous memory no longer falls back to evicting page
   cache, ensures reclaim_store() returns accurate error codes instead
   of collapsing all failures into -EAGAIN, and removes the obsolete
   gfp_mask parameter from __node_reclaim().

 - "mm: mincore: misc cleanups" (Kefeng Wang)

   Clean up and simplifies the mincore code. Most importantly, it
   removes the historical special behavior that always reports VM_PFNMAP
   pages as non-resident.

 - "mm/huge_memory: drop dead split helper variants" (Kiryl Shutsemau)

   Two trivial cleanups in the folio split API

 - "mm/damon: fix uninitialized DAMOS field and kunit exec expectation
   bugs" (SJ Park)

   Resolve minor operational and testing bugs in DAMON identified by
   Sashiko. It initializes the damos->last_applied field to prevent
   occasional efficiency degradation and fixes invalid memory accesses
   in DAMON KUnit tests during test failure handling.

 - "cleanup for stable_page_flags()" (Jinjiang Tu)

   Clean up and refactor stable_page_flags() used by /proc/kpageflags
   without altering functionality.

   It uses BIT_ULL() to prevent shift-overflow warnings on 64-bit flag
   bits, converts folio-specific flag checks to standard folio_test_*()
   helpers, and removes redundant CONFIG_PAGE_IDLE_FLAG handling.

 - "Batch unmap of uffd-wp file folios" (Dev Jain)

   Extend batched folio unmapping support to file folios within
   userfaultfd write-protect (uffd-wp) VMAs by adding batching
   capabilities to pte_install_uffd_wp_if_needed().

   This removes special-case restrictions on uffd-wp VMAs in
   try_to_unmap_one(), significantly simplifying the function's control
   flow and complexity.

 - "mm/early_ioremap: clarify and clean up early_ioremap_reset()"
   (Sang-Heon Jeon)

   Clarify and clean up the architecture-specific usage of
   __late_set_fixmap() and __late_clear_fixmap() after
   early_ioremap_reset()

   It adds explicit documentation regarding when early_ioremap_reset()
   must be called and removes redundant macro definitions and reset
   calls in the RISC-V and ARM64 architectures.

 - "mm: fix reclaim storms in defrag_mode" (Johannes Weiner)

   Address severe performance regressions, swap storms, and spurious
   OOMs caused by vm.defrag_mode=1 under high memory pressure in Meta
   production

   It updates the page allocator slowpath so non-movable allocation
   requests actively trigger direct reclaim and direct compaction at
   pageblock_order scale, allowing them to claim whole pageblocks rather
   than spinning unproductively.

 - "zram: lockmap tweaks" (Sebastian Siewior)

   Optimize and fix lockdep tracking for zram devices by consolidating
   per-entry lockmaps and isolate lock classes across multiple instances

   This reduces memory overhead by replacing per-entry lockdep_map
   instances with a single map per struct zram, and assigns a dynamic
   lock_class_key to each instance to prevent false deadlock reports
   when different zram devices are backed by distinct filesystems.

* tag 'mm-stable-2026-08-18-18-39' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (501 commits)
  selftests/mm: thuge-gen: fix test_shmget() for PAGE_SIZE check
  selftests/mm: unpoison pages in memory-failure teardown
  mm/shmem: downgrade final i_blocks check in shmem_evict_inode() to pr_warn()
  mm/khugepaged: replace mutex_lock/mutex_unlock usage with guard macro
  mm/zsmalloc: fix release order of locks in zs_page_migrate()
  Documentation: zram: remove sections numbering
  ksm: stop iterating VMAs when ksm_test_exit returns true
  mm: fold userfaultfd_rwp() to false without CONFIG_ARCH_HAS_PTE_PROTNONE
  mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch()
  zram: use a custom key for each zram object
  zram: move lockmap to be per-zram instead per table
  selftests/mm: fix gup_longterm EINVAL error message
  mm: page_alloc: fix non-movable reclaim storm in defrag_mode
  mm: page_alloc: move capture_control to the page allocator
  mm: compaction: support non-movable compaction for pageblock requests
  mm: page_alloc: __GFP_FS lockdep annotation for direct compaction
  hugetlb: evaluate subpool free state while locked
  mm/damon: remove trailing semicolons after function definitions
  mm/damon/ops-common: prevent migration fallback to non-target nodes
  mm/damon: update outdated comment about DAMOS filter handling
  ...
2026-08-20 18:17:08 -07:00
Aleksandr Nogikh
5ae1a690c5 ALSA: core: Fix use-after-free in snd_card_do_free()
A use-after-free was detected in snd_card_do_free() when a sound card
managed by devres is unbound while a user-space application still holds an
open file descriptor.

For managed cards, the memory is allocated using devres_alloc(), and its
release function is set to __snd_card_release(), which calls
snd_card_free(). When the device is unbound, the unbind thread calls
snd_card_free(), which drops a reference to the card's device. If the user
thread still has an open file descriptor, the reference count does not
reach zero, and the unbind thread blocks on wait_for_completion(&released).

When the user thread closes the file descriptor, it drops the final
reference, invoking the device release callback release_card_device(),
which calls snd_card_do_free(). snd_card_do_free() performs cleanup and
calls complete(card->release_completion). This wakes up the unbind thread,
which returns from snd_card_free() and __snd_card_release(). The devres
core then immediately frees the memory block containing the snd_card
structure.

Meanwhile, the user thread continues execution in snd_card_do_free() and
evaluates `if (!card->managed)`. It reads the `managed` boolean from the
snd_card structure that was just freed by the unbind thread, triggering a
KASAN use-after-free.

Fix this by caching the value of card->managed in a local variable before
calling complete(). This ensures that the card pointer is not dereferenced
after the unbind thread has been woken up and potentially freed the card.

BUG: KASAN: use-after-free in snd_card_do_free sound/core/init.c:604
[inline]
BUG: KASAN: use-after-free in release_card_device+0x1ab/0x1b0
sound/core/init.c:153
Read of size 1 at addr ffff8881912ec909 by task syz-executor130/5857

Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 snd_card_do_free sound/core/init.c:604 [inline]
 release_card_device+0x1ab/0x1b0 sound/core/init.c:153
 device_release+0xc4/0x1f0 drivers/base/core.c:-1
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x222/0x550 lib/kobject.c:737
 snd_card_file_remove+0x331/0x390 sound/core/init.c:1125
 snd_pcm_release+0x12c/0x160 sound/core/pcm_native.c:2986
 __fput+0x418/0xa50 fs/file_table.c:512
 fput_close_sync+0x11f/0x240 fs/file_table.c:617
 __do_sys_close fs/open.c:1511 [inline]
 __se_sys_close fs/open.c:1496 [inline]
 __x64_sys_close+0x7e/0x110 fs/open.c:1496
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
 </TASK>

Fixes: e8ad415b7a ("ALSA: core: Add managed card creation")
Assisted-by: Gemini:gemini-3.6-flash Gemini:gemini-3.1-pro-preview syzbot
Reported-by: syzbot+7061d72c26b7daebe2b4@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=7061d72c26b7daebe2b4
Link: https://syzkaller.appspot.com/ai_job?id=24752a23-f0b6-49c1-bf20-4fa89c2e7eb2
Signed-off-by: Aleksandr Nogikh <nogikh@google.com>
Link: https://patch.msgid.link/02042186-27b7-42a9-b64e-f93ce8fbe05a@mail.kernel.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-08-14 14:13:22 +02:00
John Keeping
403f7f3ad3 ALSA: seq: midi: Serialize input teardown with event_input
snd_midi_input_event() must not be running while a rawmidi substream is
closing, since this can lead to the trigger state becoming out-of-step
through this sequence in snd_rawmidi_input_trigger():

	snd_rawmidi_input_trigger(up=0)
					snd_midi_input_event()
					 -> snd_rawmidi_kernel_read()
					     -> snd_rawmidi_input_trigger(up=1)
	  -> cancel_work_sync()

which ends with the underlying device being active unexpectedly.

When this is called from close_substream(), further input can re-trigger
the input event leaving it running after rawmidi_release_priv() has set
rfile->rmidi to NULL which leads to:

	Unable to handle kernel NULL pointer dereference at virtual address 00000000000000b0
	Call trace:
	 snd_midi_input_event+0x3c/0x134 [snd_seq_midi] (P)
	 snd_rawmidi_input_event_work+0x1c/0x2c
	 process_one_work+0x150/0x3a4
	 worker_thread+0x190/0x318

Apply a similar approach to commit ef7607ab1c ("ALSA: seq: midi:
Serialize output teardown with event_input") which fixed the same issue
in the output direction, but updated to use RCU following Takashi Iwai's
proposed follow-on patch [1].

With this change in place, midisynth_unsubscribe() clears the input file
so snd_midi_input_event() will not re-trigger the stream and will be
quiesced by the cancel_work_sync() in snd_rawmidi_input_trigger().

[1] https://lore.kernel.org/linux-sound/20260813144224.753399-1-tiwai@suse.de/

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: John Keeping <jkeeping@inmusicbrands.com>
Link: https://patch.msgid.link/20260813150810.795393-1-jkeeping@inmusicbrands.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-08-13 18:21:51 +02:00
Takashi Iwai
4cc25cdd3c ALSA: seq: midi: Optimize event_input locking with RCU
The recent fix for serializing the output teardown introduced a
spinlock invocation at every MIDI output event via event_process_midi.
Since this is a hot path, let's do performance optimization with RCU.

The new output_substream __rcu pointer is published via
rcu_assign_pointer() in midisynth_use() after output_rfile is set, and
cleared in midisynth_unuse() before the resource teardown.
event_process_midi() reads it under rcu_read_lock() and bumps
output_use_lock inside that section, which is necessary to close the
window between the pointer dereference and the refcount increment.

midisynth_unuse() calls synchronize_rcu() before snd_use_lock_sync():
this guarantees that any reader who obtained a non-NULL pointer has
already called atomic_inc (output_use_lock), so the subsequent
snd_use_lock_sync() sees the correct in-flight count.

Fixes: ef7607ab1c ("ALSA: seq: midi: Serialize output teardown with event_input")
Link: https://patch.msgid.link/20260813144224.753399-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-08-13 18:21:17 +02:00
Takashi Iwai
a47bc1c7c4 ALSA: kunit: Drop __force casts
Now that the bitwise parameter definitions are gone for PCM
parameters, we don't have to cast with ugly __force prefix.
Simply drop those superfluous casts

Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260812060557.80445-7-tiwai@suse.de
2026-08-13 16:43:27 +02:00
Takashi Iwai
01edf81ac8 ALSA: oss: Drop __force casts
Now that the bitwise parameter definitions are gone for PCM
parameters, we don't have to cast with ugly __force prefix.
Simply drop those superfluous casts.

Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260812060557.80445-6-tiwai@suse.de
2026-08-13 16:43:27 +02:00
Takashi Iwai
cfea0fbbdb ALSA: control: Drop __force casts
Now that the bitwise parameter definitions are gone for control
parameters, we don't have to cast with ugly __force prefix.
Simply drop those superfluous casts.

Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260812060557.80445-5-tiwai@suse.de
2026-08-13 16:43:27 +02:00
Takashi Iwai
3850dce65e ALSA: pcm: Drop __force casts
Now that the bitwise parameter definitions are gone for PCM
parameters, we don't have to cast with ugly __force prefix.
Simply drop those superfluous casts.

Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260812060557.80445-3-tiwai@suse.de
2026-08-13 16:43:27 +02:00
HyeongJun An
0414dd7b6f ALSA: seq: Drop the dead struct snd_seq_event_bounce
The struct describes a bounce payload of an error code followed by the
original event and its external data.  No kernel has ever sent that.
Before commit efc86691e4 ("ALSA: seq: Fix kernel heap address leak in
bounce_error_event()") the kernel emitted no SNDRV_SEQ_EVENT_BOUNCE at
all, and since then it sends the event record alone.

Nothing has ever read it either.  Its only accessor,
snd_seq_event_bounce_ext_data(), has had no caller for the whole git
history, and it did not even compile until commit c7e0b5bf9f ("[ALSA]
Remove xxx_t typedefs: Sequencer") incidentally repaired the type name
it referred to, three years after the git import.  Drop the accessor
along with the struct.

This removes a definition from a UAPI header.  Since no kernel ever
produced the layout, nothing can have parsed it, but a program that
merely names the type will need to stop.

Suggested-by: Takashi Iwai <tiwai@suse.de>
Assisted-by: Claude:claude-opus-5
Signed-off-by: HyeongJun An <sammiee5311@gmail.com>
Link: https://patch.msgid.link/20260812141506.4016387-1-sammiee5311@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-08-12 16:39:11 +02:00
HyeongJun An
59e1592d3c ALSA: seq: Don't leak the extension cell pointer in the bounce payload
The bounce_error_event() embeds the failed event in the bounce payload
by pointing data.ext.ptr at it.  When that event is a queued
variable-length event, its own data.ext.ptr holds the address of its
first extension cell, put there by snd_seq_event_dup().  The payload
goes out verbatim through snd_seq_expand_var_event(), so the address
reaches userspace.

That is the same address commit 705dd6dcbc ("ALSA: seq: Clear
variable event pointer on read") removed from the event header.  The
read path still clears it there, just above the call that expands the
payload.

Embed a sanitised copy instead, treated exactly as snd_seq_read()
treats the header.  A stack copy is enough because delivery is
synchronous and snd_seq_event_dup() copies before returning.

An unprivileged client reaches this by setting SNDRV_SEQ_FILTER_BOUNCE,
queueing a variable-length event to a port that does not exist and
reading the bounce back.  Eight bytes on 64-bit, from its own pool.

Fixes: efc86691e4 ("ALSA: seq: Fix kernel heap address leak in bounce_error_event()")
Assisted-by: Claude:claude-opus-5
Signed-off-by: HyeongJun An <sammiee5311@gmail.com>
Link: https://patch.msgid.link/20260811131835.3837024-1-sammiee5311@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-08-11 18:19:06 +02:00
Takashi Iwai
0252ad169c ALSA: seq: Use RCU for the UMP client output substream
The UMP sequencer client protects its output rawmidi file (out_rfile)
with an rwlock (output_lock).  seq_ump_process_event(), the port's
event_input callback, reads out_rfile.output under read_lock on every
delivered UMP event, while the open/close paths (serialized by
ump->open_mutex) publish and clear out_rfile under write_lock.

Output is opened/closed only on the subscribe/use lifecycle while
delivery happens per event, so this is another read-mostly hot path.
Convert it to RCU and drop the rwlock.  out_rfile is an embedded struct
rather than a pointer, so instead of restructuring it, add an
RCU-protected shadow of the substream (out_substream) for the reader;
out_rfile itself becomes writer-only state accessed solely under
open_mutex.  The reader now runs lock-free under rcu_read_lock() via
rcu_dereference(), and open publishes the substream with
rcu_assign_pointer().

On close the substream is cleared with rcu_assign_pointer(NULL) and the
rawmidi is released only after synchronize_rcu(), so no reader in the
delivery path can still be writing to the substream when
snd_rawmidi_kernel_release() runs.

Dropping write_lock_irqsave() from the writers is safe: they run in
process context under open_mutex, and the sole atomic reader now uses
RCU, which is IRQ-safe.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260810133711.42483-6-tiwai@suse.de
2026-08-10 17:44:34 +02:00
Takashi Iwai
7ffa5d2462 ALSA: seq: Use RCU for the virmidi file list
Each virmidi device keeps a list of its opened input files (filelist)
protected by both an rwlock (filelist_lock) and a rw_semaphore
(filelist_sem).  snd_virmidi_dev_receive_event() walks the list on the
sequencer event input path -- read_lock() when the event is delivered in
atomic context, down_read() otherwise -- decoding each incoming event
into the file's rawmidi buffer.  The writers (input open/close) take both
locks to add/remove entries.

This is another typical dual-lock read-mostly pattern as the port
subscriber list: files are opened/closed rarely while the receive
callback runs per event.  Let's convert the traversal to RCU and drop
the rwlock; the existing filelist_sem keeps serializing the writers.
The atomic input path now runs lock-free under rcu_read_lock(), and
both readers share a single list_for_each_entry_rcu() (valid under the
rwsem via lockdep_is_held()).  The writers switch to
list_add_tail_rcu() / list_del_rcu().

snd_virmidi_input_close() freed the entry (parser and struct)
immediately after list_del.  A concurrent lockless reader in the atomic
path may still be dereferencing it, so the close path now waits for an
RCU grace period after list_del_rcu() before freeing; synchronize_rcu()
is used rather than kfree_rcu() because the parser must also be released
after the grace period, not just the struct.  Non-atomic readers are
already excluded by the down_write, so only the atomic RCU readers need
the grace period.

Dropping write_lock_irq() from the writers is safe: no writer runs in
atomic/IRQ context, and the sole atomic reader now uses RCU, which is
IRQ-safe.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260810133711.42483-5-tiwai@suse.de
2026-08-10 17:44:34 +02:00
Takashi Iwai
7a287e4615 ALSA: seq: Use RCU for the client table
The sequencer keeps a global table of clients (clienttab[]) indexed by
client id, protected by the global clients_lock spinlock.  The lookup
snd_seq_client_use_ptr() reads a slot and takes a use_lock reference on
the client, and this runs on the event delivery hot path: every
dispatched event resolves its destination (and often source) client
through it.  The spinlock's only job on the read side is to make the
"pointer is non-NULL" test and the reference increment indivisible with
respect to the writer that nulls the slot and then drains the refcount.

Clients come and go rarely but delivery happens constantly, so this is
yet another read-mostly case as the port and subscriber lists.
Convert the table to RCU: the read side now runs lock-free under
rcu_read_lock() and takes the use_lock reference via
rcu_dereference(), removing contention on the single global spinlock
from the delivery path.  The writers keep clients_lock (still needed
to serialize slot allocation) and publish / unpublish via
rcu_assign_pointer(); creation and destruction remain serialized at a
higher level by register_mutex.

As with the ports, the client is not freed via kfree_rcu(): its lifetime
is governed by the use_lock refcount drained in seq_free_client1().
list_del under the old spinlock excluded a concurrent lookup from taking
a new reference once the slot was nulled; rcu_assign_pointer(NULL) offers
no such exclusion, so a reader still holding the old pointer can grab a
reference after the unpublish.  seq_free_client1() therefore calls
synchronize_rcu() after nulling the slot and before snd_use_lock_sync():
once the grace period elapses no new reference can appear, and the
existing drain then frees the client safely.

clienttablock[] keeps its slot-reservation role (create/free are
serialized by register_mutex); its read on the lookup path only gates
module autoload, so a lockless read is harmless.  Dropping the spinlock
from the read path is safe: clients_lock is now taken only by the
process-context writers, and the sole atomic reader uses RCU, which is
IRQ-safe.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260810133711.42483-4-tiwai@suse.de
2026-08-10 17:44:34 +02:00
Takashi Iwai
4c252fbc06 ALSA: seq: Use RCU for the client port list
Each sequencer client keeps a list of its ports (ports_list_head)
protected by both an rwlock (ports_lock) and a mutex (ports_mutex).
The rwlock is taken read-side on the event delivery hot path:
snd_seq_port_use_ptr() walks the list to resolve a port on every
dispatched event, while the mutex serializes port creation/deletion.

Ports change rarely but delivery happens constantly, so this is the
another read-mostly case as the port subscriber list.  Convert the
port list traversal to RCU and drop the rwlock entirely; the existing
ports_mutex keeps serializing the writers.  The atomic delivery path
(snd_seq_port_use_ptr(), snd_seq_port_query_nearest()) now runs
lock-free under rcu_read_lock() instead of contending on the shared
rwlock.

The writers switch to list_add_tail_rcu()/list_del_rcu().
snd_seq_insert_port() now stores the port number and name before
publishing the node so RCU readers only ever observe a fully
initialized port.  One drawback is that snd_seq_delete_all_ports()
drops the O(1) splice trick and unlinks each port individually,
though: the splice repointed the last port's ->next away from the list
head, which would send a concurrent lockless reader off the end of the
list.

Unlike the subscriber objects, ports are not freed via kfree_rcu():
port_delete() must drain outstanding use_lock references (and run
private_free()) synchronously.  The rwlock previously guaranteed that
no reader could take a new use_lock reference once the port was
unlinked -- list_del under write_lock excluded snd_use_lock_use()
under read_lock.  list_del_rcu() offers no such exclusion, so a reader
still traversing the list can grab a reference after the unlink.
port_delete() therefore calls synchronize_rcu() after the port has
been unlinked and before snd_use_lock_sync(): once the grace period
elapses no new reference can appear, and the existing drain then frees
the port safely.

Dropping write_lock_irq() from the writers is safe: no writer runs in
atomic/IRQ context, and the sole atomic reader now uses RCU, which is
IRQ-safe.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260810133711.42483-3-tiwai@suse.de
2026-08-10 17:44:34 +02:00
Takashi Iwai
a9760db775 ALSA: seq: Use RCU for the port subscriber list
Each sequencer port keeps two subscriber groups (c_src and c_dest),
each protected by both an rwlock (list_lock) and a rw_semaphore
(list_mutex).  The rwlock is taken read-side in the event delivery hot
path (__deliver_to_subscribers()) for delivering every event to
subscribers, while the mutex serializes subscribe/unsubscribe and
covers the sleepable delivery and query walks.

Subscriptions change rarely but delivery happens constantly, so this is
a textbook read-mostly case.  Convert the subscriber list traversal to
RCU and drop the rwlock entirely while keeping the existing list_mutex
for serializing the writers.  The atomic delivery path now runs
lock-free under rcu_read_lock() instead of contending on the shared
rwlock.

Along with the conversion to RCU, the subscriber lists are switched
from list_head to hlist so that removal can use hlist_del_init_rcu():
it keeps the ->next pointer intact for concurrent readers while
clearing ->pprev, which lets the double-deletion guard (added in
commit 13d5e5d472) keep detecting an already-removed entry via
hlist_unhashed().

Dropping write_lock_irq() from the writers is safe: no writer runs in
atomic/IRQ context, and the sole atomic reader now uses RCU, which is
IRQ-safe.  Port lifetime handling (use_lock/closing drain in
port_delete()) is orthogonal and unchanged.

Note that the conversion to RCU has another merit: it automatically
"fixes" the (rather false) lockdep warnings for the doubly read-locks
of the same subscriber list, too.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260810133711.42483-2-tiwai@suse.de
2026-08-10 17:44:34 +02:00
HyeongJun An
8a906c0b4f ALSA: ump: Fix corrupted data bytes at MIDI 1.0 SysEx to UMP conversion
The cvt_legacy_sysex_to_ump() initialises only the first word of the
output packet and ORs the data bytes into it.  The second word is left
alone, and the conversion context is kept across calls, so it still
carries the previous packet's bytes.  Those stale bits corrupt the new
data.  Any SysEx longer than six data bytes is affected.

A SysEx with the twelve data bytes 01..0c comes out as:

  30160102 03040506
  30260708 0b0e0f0e

The second packet declares six data bytes and four of them are wrong,
inside the declared length.

The sibling cvt_legacy_cmd_to_ump() already clears the second word.  Do
the same here.

Fixes: 0b5288f5fe ("ALSA: ump: Add legacy raw MIDI support")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-5
Signed-off-by: HyeongJun An <sammiee5311@gmail.com>
Link: https://patch.msgid.link/20260808014554.3550153-1-sammiee5311@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-08-08 09:01:34 +02:00
Lorenzo Stoakes
a2fdfd0080 mm: introduce vma_get_page_prot() and use it
There's a large number of vm_get_page_prot(vma->vm_flags) invocations. 
Make life easier by introducing vma_get_page_prot() parameterised by the
VMA.

This also makes converting vm_get_page_prot() to vma_flags_t easier.

Also update the userland VMA tests to reflect the change.

No functional change intended.

Link: https://lore.kernel.org/20260711-b4-vma-flags-mm-v2-8-0fa2357d5431@kernel.org
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
Acked-by: Zi Yan <ziy@nvidia.com>
Acked-by: Jani Nikula <jani.nikula@intel.com> # for i915
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>	[DRM]
Reviewed-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Dave Airlie <airlied@gmail.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Nico Pache <npache@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pedro Falcato <pfalcato@suse.de>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:03 -07:00
Takashi Iwai
9c04742e73 ALSA: rawmidi: Work around false-positive mutex lockdep warning
When opening a legacy rawmidi device for a UMP, it may re-open an
existing rawmidi device for appending to a substream, leading to a
lockdep warning due to rmidi->open_mutex taken twice -- but the
rawmidi devices are completely individual, hence it's a
false-positive.

For avoiding the warning, modify the helper to open a rawmidi instance
with a proper locking subclass from the UMP legacy open.

Unfortunately, there is no good way to achieve it with guard(), so
reverted to the manual mutex calls again.

Reported-by: syzbot+d10d58fc99caa0489796@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/6a6a9634.57649fcc.360844.000b.GAE@google.com
Link: https://patch.msgid.link/20260806101352.1291581-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-08-06 17:02:22 +02:00
Maciej Strozek
86cac980c9 ALSA: control: add ioctl to retrieve full card components
The fixed-size components field in SNDRV_CTL_IOCTL_CARD_INFO can be too
small on systems with many audio devices.

Keep the existing struct snd_ctl_card_info ABI intact and add a new
ioctl SNDRV_CTL_IOCTL_CARD_BYTES that carries a variable-length payload
selected by a type discriminator. The first defined type
SND_CTL_CARD_BTYPE_COMPONENTS returns the full components string. The
ioctl is designed to be reused for other variable-length card payloads
in the future.

The user-space caller may set data_allocated == 0 (or data == NULL) to
query the required length; otherwise the kernel copies the payload into
the user buffer and writes back the actual length in data_len.

When the legacy components field in struct snd_ctl_card_info is
truncated, '>' is written just before the NUL terminator to signal to
user-space that the full string is available via the new ioctl.

card->components is now dynamically allocated and grown in 32 byte
increments via krealloc(), capped at 512 bytes.

Link: https://github.com/alsa-project/alsa-lib/pull/494
Suggested-by: Jaroslav Kysela <perex@perex.cz>
Suggested-by: Takashi Iwai <tiwai@suse.com>
Signed-off-by: Maciej Strozek <mstrozek@opensource.cirrus.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260720103505.1860399-2-mstrozek@opensource.cirrus.com
2026-08-05 09:28:59 +02:00
Maciej Strozek
eaf46ee965 ALSA: control: tidy up whitespaces
Clean up trailing whitespace in preparation for the card components
changes.

Signed-off-by: Maciej Strozek <mstrozek@opensource.cirrus.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260720103505.1860399-1-mstrozek@opensource.cirrus.com
2026-08-05 09:28:58 +02:00
Takashi Iwai
cbae176309 Merge branch 'for-linus' into for-next
Pull 7.2 devel branch for applying further patches cleanly.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-07-30 11:28:26 +02:00
Norbert Szetei
f495b6c4c8 ALSA: pcm: wake linked drain waiters on unlink
snd_pcm_drain() on a linked stream parks an on-stack wait entry on the
drained peer's runtime->sleep, and after schedule_timeout() removes it
only if that peer is still found in the caller's group.  If group
membership changes during the wait and the sleep ends by signal or
timeout (so autoremove_wake_function() does not run), finish_wait() is
skipped and snd_pcm_drain() returns with the entry still queued on that
stream's sleep list; a later wake_up() then walks a freed stack frame.
This is reachable by unlinking either the drained or the draining stream.

Unlike the close path (snd_pcm_drop() -> snd_pcm_post_stop()),
snd_pcm_unlink() never wakes the sleep queues.  Wake every group member
under the group lock before the membership change, so a linked drainer is
released and drops its entry while the streams are still grouped.

The window was opened when snd_pcm_link_rwsem stopped being held across
the wait and the removal became conditional on group membership (see
Fixes). The later switch to finish_wait() kept that conditional removal,
so the signal/timeout case remained.

Fixes: f57f3df03a ("ALSA: pcm: More fine-grained PCM link locking")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-5
Signed-off-by: Norbert Szetei <norbert@doyensec.com>
Link: https://patch.msgid.link/A0705100-D10B-4286-9980-0142ABEEAD51@doyensec.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-07-28 18:29:48 +02:00
Norbert Szetei
c2744d5f3a ALSA: timer: Clear SNDRV_TIMER_IFLG_DEAD once the close completes
snd_timer_close_locked() marks an instance with SNDRV_TIMER_IFLG_DEAD
and returns early when the flag is already set, but the flag is never
cleared again.  A completed close ends in remove_slave_links(), which
leaves timeri->timer NULL, so a second close is already harmless through
the timer == NULL path; the early return can only be reached by an
instance that was opened again in between.  For such an instance the
close unlinks nothing, so snd_timer_instance_free() frees an object that
is still on timer->open_list_head, still on snd_timer_master_list if it
was opened with a slave key, still owns any adopted slaves, and still
holds its timer and module references.

snd_seq_timer_open() reopens an instance exactly like that: it retries
its fallback open on the same object after a failure that has already
run snd_timer_close_locked() internally.  An unprivileged user with
access to /dev/snd/timer and /dev/snd/seq can force that failure, since
snd_timer_check_master() returns -EBUSY when a pending slave matches the
new master's (slave_class, slave_id) key and the target timer has
reached max_instances, and SNDRV_TIMER_IOCTL_SELECT with dev_class =
SNDRV_TIMER_CLASS_SLAVE keeps the caller-supplied dev_sclass, so a
sequencer queue's key can be forged.  The freed instance is afterwards
dereferenced by any further snd_timer_open() on that timer, by
snd_timer_check_slave(), and by /proc/asound/timers, which faults on the
stale ti->owner pointer.

The flag only has to be visible while the close is in progress, which is
all its other users need.  Clear it in remove_slave_links(), under the
same timer->lock that sets it, once the instance is off every list.

Fixes: da3039e91d ("ALSA: timer: Forcibly close timer instances at closing")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-5
Signed-off-by: Norbert Szetei <norbert@doyensec.com>
Link: https://patch.msgid.link/CA41AA48-75BF-45E9-A36D-3A5D2F124F60@doyensec.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-07-26 16:11:45 +02:00
Baul Lee
70c977815a ALSA: ump: fix double free of out_cvts on rawmidi error
snd_ump_attach_legacy_rawmidi() allocates the legacy conversion array
ump->out_cvts and, on the snd_rawmidi_new() error path, frees it with
kfree() but leaves ump->out_cvts pointing at the freed memory.  When the
endpoint is later torn down, snd_ump_endpoint_free() frees ump->out_cvts
a second time, resulting in a double free.

The host snd-usb-audio driver attaches the legacy rawmidi for any USB
MIDI 2.0 (UMP) device, so a device that makes snd_rawmidi_new() fail
reaches this path on enumeration.

Clear ump->out_cvts after freeing it on the error path so it is not
freed again during teardown.

Discovered by XBOW, triaged by Baul Lee <baul.lee@xbow.com>

Fixes: 33cd763078 ("ALSA: ump: Export MIDI1 / UMP conversion helpers")
Reported-by: Federico Kirschbaum <federico.kirschbaum@xbow.com>
Reported-by: Baul Lee <baul.lee@xbow.com>
Cc: stable@vger.kernel.org
Signed-off-by: Baul Lee <baul.lee@xbow.com>
Link: https://patch.msgid.link/20260726051633.41206-1-baul.lee@xbow.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-07-26 08:59:26 +02:00
Norbert Szetei
21e1968843 ALSA: seq: Fix division by zero in initialize_timer()
A userspace-driven ALSA timer (SND_UTIMER) lets an unprivileged user set
the backing snd_timer's hardware resolution to an arbitrary 64-bit value
via SNDRV_TIMER_IOCTL_CREATE. snd_utimer_create() only rejects zero.

When such a timer is bound to a sequencer queue, initialize_timer()
computes the tick period as

	tmr->ticks = 1000000000 / (r * freq);

where r is that user-controlled resolution and freq is the sequencer
update rate in Hz, clamped to MIN_FREQUENCY..MAX_FREQUENCY (10..6250).
A resolution of 2^63 makes the 64-bit product r * freq wrap to zero for
any even freq, including DEFAULT_FREQUENCY (1000), so the division faults
with a divide-by-zero.

The division runs under tmr->lock with interrupts disabled, so the oops
leaves the spinlock held and hangs the CPU. It is reachable by an
unprivileged user with access to /dev/snd/timer and /dev/snd/seq.

  Oops: divide error: 0000 [#1] SMP KASAN PTI
  CPU: 7 UID: 1000 PID: 456 Comm: alsa_seq_utimer Not tainted 7.2.0-rc4+
  RIP: 0010:initialize_timer.constprop.0+0x20a/0x2d0
   snd_seq_timer_start+0x15e/0x2b0
   snd_seq_control_queue+0x56f/0xba0
   snd_seq_write+0x3e0/0x730

Reject an overflowing product with check_mul_overflow() and fall back to
a single tick, which also avoids feeding a wrapped-but-nonzero divisor
(e.g. 2^63 * 1000 mod 2^64 == 0, or other resolutions wrapping to a small
value) into the period computation.

Fixes: 37745918e0 ("ALSA: timer: Introduce virtual userspace-driven timers")
Cc: <stable@vger.kernel.org>
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Norbert Szetei <norbert@doyensec.com>
Link: https://patch.msgid.link/DF8A3844-AD5E-4B8A-9CFC-BD83C212BA38@doyensec.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-07-25 08:53:34 +02:00
Norbert Szetei
bdefe1346a ALSA: timer: drain a slave's callback before its master detaches it
snd_timer_close_locked() drains the closing instance's own in-flight
callback (IFLG_CALLBACK) before freeing it, but not its slaves'. When a
master instance is closed, remove_slave_links() clears each slave's
->timer; the slave's own close then reads timer == NULL and takes the
branch that skips the drain entirely (snd_timer_stop_slave() also no-ops
on a NULL timer). So a slave whose callback is still running when the
master is closed is freed underneath the live callback, leading to
use-after-free.

Drain the slaves too before remove_slave_links() severs them.
snd_timer_stop() has already taken this instance off the active list, so
no new slave callback can be queued. Take the slaves off the ack list so
a pending one can't fire either, then wait for any that is already in
flight.

Fixes: 37745918e0 ("ALSA: timer: Introduce virtual userspace-driven timers")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Norbert Szetei <norbert@doyensec.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/D26598EB-DBF7-4D76-9F71-8E4BD59822D4@doyensec.com
2026-07-20 10:16:56 +02:00
Norbert Szetei
70d28bfcd6 ALSA: timer: don't re-enter an instance callback that is still running
The userspace-driven timer (utimer) TRIGGER ioctl calls
snd_timer_interrupt() directly with no serialization, so two threads
triggering the same utimer can run snd_timer_interrupt() on one
snd_timer concurrently.

snd_timer_process_callbacks() drops timer->lock around each instance
callback and marks the in-flight callback with the single
SNDRV_TIMER_IFLG_CALLBACK bit; snd_timer_close_locked() waits on that
bit to drain an in-flight callback before freeing the instance. The bit
cannot represent two concurrent callbacks: when a second interrupt
re-queues an instance whose callback is still running, both run at once,
the first to finish clears the bit, and the close-path drain then frees
the instance (and its callback_data) while the other callback is still
live - a use-after-free reachable by any user able to open
/dev/snd/timer, both via a user timer instance and via a sequencer queue
timer bound to the utimer.

snd_timer_interrupt() sets IFLG_CALLBACK before dropping timer->lock, so
a concurrent interrupt already observes it under the lock. Skip
re-queuing an instance (and its slaves) to the ack/sack list while its
callback is in flight; the accumulated pticks are delivered on the next
tick, so no event is lost.

Fixes: 37745918e0 ("ALSA: timer: Introduce virtual userspace-driven timers")
Cc: stable@vger.kernel.org
Suggested-by: Takashi Iwai <tiwai@suse.de>
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Norbert Szetei <norbert@doyensec.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/6F9B6501-8E65-4265-B02C-7EFB240D1664@doyensec.com
2026-07-20 10:16:56 +02:00
Norbert Szetei
2c4dc0ed50 ALSA: seq: close a re-opened queue timer in the destructor
queue_delete() closes the queue timer, then frees it. snd_seq_timer_close()
clears q->timer->timeri. snd_use_lock_sync() then drains borrowers, and
snd_seq_timer_delete() frees q->timer.

A borrower can re-open the timer inside that window. A SET_QUEUE_CLIENT
that took a queueptr() use_lock reference before the queue was unlinked
runs snd_seq_timer_open() after the close. Open refuses re-open only while
timeri is set, and the close just cleared it, so it re-opens timeri.

snd_seq_timer_delete() does not close that instance. Its snd_seq_timer_stop()
is a no-op, because running was cleared first. So it frees q->timer with the
instance still live. The queue is freed next.

The instance stays on the global timer with callback_data pointing at the
freed queue. A non-owner START on the unlocked queue arms it. The next tick
derefs the freed queue in snd_seq_timer_interrupt().

Reachable by an unprivileged user with access to /dev/snd/seq. No CAP and
no queue ownership required.

Close any lingering instance in the destructor. There, ->timeri can no
longer change: the queue is unlinked and all use_lock borrowers have
drained, so no snd_seq_queue_use() can re-open it. Close it before clearing
q->timer. snd_timer_close() waits for any in-flight snd_seq_timer_interrupt()
to finish, and that callback still reads q->timer (via snd_seq_check_queue()),
so q->timer must stay valid until it drains.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Norbert Szetei <norbert@doyensec.com>
Link: https://patch.msgid.link/422FDB81-2A68-47C7-A22D-2D3301E2E86D@doyensec.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-07-14 11:08:59 +02:00
bui duc phuc
307835a6eb ALSA: core: Clean up file_operations definitions
Align file_operations initializers with tabs to match the standard
kernel coding style and improve readability.

Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
Link: https://patch.msgid.link/20260708140624.562403-1-phucduc.bui@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-07-13 12:01:27 +02:00
bui duc phuc
ae1f30f4bd ALSA: control: preserve snd_card_file_add() error code in snd_ctl_open()
snd_ctl_open() unconditionally overwrites the return value of
snd_card_file_add() with -ENODEV on failure, discarding the actual
error code.

Fix this by directly returning the original error code returned by
snd_card_file_add() (e.g. -ENOMEM or -ENODEV). This behavior is
consistent with the error handling used in other functions such as
snd_mixer_oss_open(), snd_hwdep_open(), snd_pcm_oss_open(), and others.

There is no functional change other than the returned error code in this
failure path.

Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260708023540.6962-1-phucduc.bui@gmail.com
2026-07-08 12:48:22 +02:00
bui duc phuc
a0a47b0ae2 ALSA: pcm: Return -ENODEV instead of -EFAULT in snd_pcm_open()
When try_module_get() fails in snd_pcm_open(), the owning module is going
away and the device is no longer usable, so -EFAULT ("bad address") is the
wrong error. Return -ENODEV, matching the other unavailable-device paths
in this function(the NULL pcm check and the card->shutdown check).
This changes the errno reported to userspace on this rare race.
No other behaviour changes.

Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260707084506.718583-7-phucduc.bui@gmail.com
2026-07-08 12:44:52 +02:00
bui duc phuc
d9468d5286 ALSA: pcm: oss: Return -ENODEV instead of -EFAULT in snd_pcm_oss_open()
When try_module_get() fails in snd_pcm_oss_open(), the owning module is
going away and the device is no longer usable, so -EFAULT ("bad address")
is the wrong error. Return -ENODEV, matching the other unavailable-device
paths in this function(the NULL pcm check and the card->shutdown check).
This changes the errno reported to userspace on this rare race.
No other behaviour changes.

Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260707084506.718583-6-phucduc.bui@gmail.com
2026-07-08 12:44:52 +02:00
bui duc phuc
fb0fb4b943 ALSA: mixer: oss: Return -ENODEV instead of -EFAULT in snd_mixer_oss_open()
When try_module_get() fails in snd_mixer_oss_open(), the owning module is
going away and the device is no longer usable, so -EFAULT ("bad address")
is the wrong error. Return -ENODEV, matching the other unavailable-device
paths in this function(the NULL card check and the NULL mixer_oss check).
This changes the errno reported to userspace on this rare race.
No other behaviour changes.

Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260707084506.718583-5-phucduc.bui@gmail.com
2026-07-08 12:44:52 +02:00
bui duc phuc
52f15bf51b ALSA: info: Return -ENODEV instead of -EFAULT in alloc_info_private()
When try_module_get() fails in alloc_info_private(), the owning module is
going away and the device is no longer usable, so -EFAULT ("bad address")
is the wrong error. Return -ENODEV, matching the other -ENODEV path in the
same function.
This changes the errno reported to userspace on this rare race.
No other behaviour changes.

Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260707084506.718583-4-phucduc.bui@gmail.com
2026-07-08 12:44:52 +02:00
bui duc phuc
c49e88ea6c ALSA: hwdep: Return -ENODEV instead of -EFAULT in snd_hwdep_open()
When try_module_get() fails in snd_hwdep_open(), the owning module is
going away and the device is no longer usable, so -EFAULT ("bad address")
is the wrong error. Return -ENODEV, matching the other unavailable-device
paths in this function(the NULL hw check and the card->shutdown check).
This changes the errno reported to userspace on this rare race.
No other behaviour changes.

Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260707084506.718583-3-phucduc.bui@gmail.com
2026-07-08 12:44:52 +02:00
bui duc phuc
b45f4e8d78 ALSA: control: Return -ENODEV instead of -EFAULT in snd_ctl_open()
When try_module_get() fails in snd_ctl_open(), the owning module is going
away and the device is no longer usable, so -EFAULT ("bad address") is the
wrong error. Return -ENODEV, matching the other unavailable-device paths
in this function(the NULL card check and the snd_card_file_add() failure).
This changes the errno reported to userspace on this rare race.
No other behaviour changes.

Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260707084506.718583-2-phucduc.bui@gmail.com
2026-07-08 12:44:52 +02:00
bui duc phuc
5171dddf10 ALSA: core: use ARRAY_SIZE() in snd_minor_info_read()
Use ARRAY_SIZE(snd_minors) instead of SNDRV_OS_MINORS directly, for
consistency with snd_find_free_minor() and snd_unregister_device() in
the same file. No functional change.

Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
Link: https://patch.msgid.link/20260707074556.569451-1-phucduc.bui@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-07-07 16:36:17 +02:00
bui duc phuc
bd8f218761 ALSA: core: propagate actual error code from register_chrdev
The alsa_sound_init() function currently returns a hardcoded -EIO
if register_chrdev() fails, masking specific error codes from
__register_chrdev() such as -EINVAL, -ENOMEM, or -EBUSY.

Masking these failures under a generic -EIO makes system-level
diagnostics unnecessarily difficult. Propagating explicit error codes
from register_chrdev() is also an established convention widely
practiced across other subsystems.

Fix this by capturing and propagating the dynamic error code from
register_chrdev(). While at it, also assign the return value of
snd_info_init() to the 'err' variable instead of hardcoding -ENOMEM
to ensure consistency and future-proofing.

Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
Link: https://patch.msgid.link/20260703103840.253527-1-phucduc.bui@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-07-03 13:07:22 +02:00
bui duc phuc
b8c89ae642 ALSA: timer: Drop redundant stream_open() return check
The previous conversion from nonseekable_open() to stream_open() retained
the existing error check.
Since stream_open() always returns 0, remove the dead error handling path.

Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260702084445.519669-8-phucduc.bui@gmail.com
2026-07-03 13:05:31 +02:00