linux/sound/core
Takashi Iwai 87988a534d ALSA: Fix deadlocks with kctl removals at disconnection
In snd_card_disconnect(), we set card->shutdown flag at the beginning,
call callbacks and do sync for card->power_ref_sleep waiters at the
end.  The callback may delete a kctl element, and this can lead to a
deadlock when the device was in the suspended state.  Namely:

* A process waits for the power up at snd_power_ref_and_wait() in
  snd_ctl_info() or read/write() inside card->controls_rwsem.

* The system gets disconnected meanwhile, and the driver tries to
  delete a kctl via snd_ctl_remove*(); it tries to take
  card->controls_rwsem again, but this is already locked by the
  above.  Since the sleeper isn't woken up, this deadlocks.

An easy fix is to wake up sleepers before processing the driver
disconnect callbacks but right after setting the card->shutdown flag.
Then all sleepers will abort immediately, and the code flows again.

So, basically this patch moves the wait_event() call at the right
timing.  While we're at it, just to be sure, call wait_event_all()
instead of wait_event(), although we don't use exclusive events on
this queue for now.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=218816
Cc: <stable@vger.kernel.org>
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20240510101424.6279-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2024-05-10 14:49:32 +02:00
..
oss ALSA: pcm: oss: Use guard() for setup 2024-02-28 15:01:22 +01:00
seq ALSA: seq: ump: Fix conversion from MIDI2 to MIDI1 UMP messages 2024-04-19 12:07:14 +02:00
.kunitconfig ALSA: core: add kunitconfig 2024-03-17 09:36:45 +01:00
compress_offload.c ALSA: compress_offload: Use guard() for locking 2024-02-28 15:01:20 +01:00
control_compat.c ALSA: control: Use guard() for locking 2024-02-28 15:01:21 +01:00
control_led.c ALSA: control_led: Use guard() for locking 2024-02-28 15:01:22 +01:00
control.c ALSA: control: Fix unannotated kfree() cleanup 2024-03-20 07:30:48 +01:00
ctljack.c ALSA: Convert strlcpy to strscpy when return value is unused 2021-01-08 09:30:05 +01:00
device.c ALSA: core: Fix missing return value comments for kernel docs 2022-07-13 13:42:38 +02:00
hrtimer.c ALSA: hrtimer: Use guard() for locking 2024-02-28 15:01:20 +01:00
hwdep_compat.c ALSA: compat_ioctl: avoid compat_alloc_user_space 2020-09-21 10:37:07 +02:00
hwdep.c ALSA: hwdep: Move put_user() call out of scoped_guard() in snd_hwdep_control_ioctl() 2024-03-01 18:10:57 +01:00
info_oss.c ALSA: info: Use guard() for locking 2024-02-28 15:01:21 +01:00
info.c ALSA: info: Use guard() for locking 2024-02-28 15:01:21 +01:00
init.c ALSA: Fix deadlocks with kctl removals at disconnection 2024-05-10 14:49:32 +02:00
isadma.c sound updates for 6.0-rc1 2022-08-06 10:19:51 -07:00
jack.c ALSA: jack: Use guard() for locking 2024-02-28 15:01:21 +01:00
Kconfig ALSA: core: Fix dependencies for SND_CORE_TEST 2024-02-02 09:16:46 +01:00
Makefile Merge branch 'for-linus' into for-next 2024-02-21 11:17:06 +01:00
memalloc_local.h ALSA: memalloc: remove snd_dma_sg_ops declaration 2022-09-09 09:09:40 +02:00
memalloc.c ALSA: memalloc: Workaround for Xen PV 2023-01-27 09:16:24 +01:00
memory.c ALSA: core: Add memory copy helpers between iov_iter and iomem 2023-08-18 12:18:16 +02:00
misc.c ALSA: core: Add async signal helpers 2022-07-29 12:57:10 +02:00
pcm_compat.c ALSA: pcm: Use guard() for PCM stream locks 2024-02-28 15:01:22 +01:00
pcm_dmaengine.c ALSA: dmaengine: increment buffer pointer atomically 2022-09-27 08:55:05 +02:00
pcm_drm_eld.c drm/edid: include drm_eld.h only where required 2023-11-09 16:47:31 +02:00
pcm_iec958.c ALSA: iec958: Split status creation and fill 2021-06-08 17:05:41 +02:00
pcm_lib.c ALSA: pcm: Use guard() for PCM stream locks 2024-02-28 15:01:22 +01:00
pcm_local.h ALSA: pcm: Revert "ALSA: pcm: rewrite snd_pcm_playback_silence()" 2023-05-05 18:23:48 +02:00
pcm_memory.c ALSA: pcm: Use guard() for locking 2024-02-28 15:01:22 +01:00
pcm_misc.c ALSA: pcm: Test for "silence" field in struct "pcm_format_data" 2022-04-11 09:27:56 +02:00
pcm_native.c Merge branch 'for-next' into for-linus 2024-03-11 09:12:58 +01:00
pcm_param_trace.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pcm_timer.c ALSA: timer: Constify snd_timer_hardware definitions 2020-01-03 09:24:07 +01:00
pcm_trace.h ALSA: pcm: fix tracing reason in hw_ptr_error 2022-11-28 14:55:41 +01:00
pcm.c ALSA: pcm: Use guard() for locking 2024-02-28 15:01:22 +01:00
rawmidi_compat.c ALSA: rawmidi: Replace with __packed attribute 2023-10-26 09:42:55 +02:00
rawmidi.c ALSA: rawmidi: Use guard() for locking 2024-02-28 15:01:21 +01:00
seq_device.c ALSA: seq: make snd_seq_bus_type const 2024-02-15 13:48:03 +01:00
sound_kunit.c ALSA: kunit: Fix sparse warnings 2024-02-28 15:00:18 +01:00
sound_oss.c ALSA: core: Use guard() for locking 2024-02-28 15:01:21 +01:00
sound.c ALSA: core: Use guard() for locking 2024-02-28 15:01:21 +01:00
timer_compat.c ALSA: timer: Use guard() for locking 2024-02-28 15:01:20 +01:00
timer.c ALSA: timer: Fix missing irq-disable at closing 2024-03-15 11:16:47 +01:00
ump_convert.c ALSA: ump: Correct wrong byte size at converting a UMP System message 2023-06-28 11:44:30 +02:00
ump.c ALSA: ump: Use guard() for locking 2024-02-28 15:01:20 +01:00
vmaster.c ALSA: vmaster: Use automatic cleanup of kfree() 2024-02-23 10:57:30 +01:00