diff options
| author | Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> | 2022-09-19 15:10:40 +0300 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2022-09-20 09:08:14 +0300 |
| commit | ac3467ad7f8734a21b65fa1852316a9b1b8c1fad (patch) | |
| tree | 0a3e95b90048cd5ec7dd71369021b627eb7d600d | |
| parent | 53f4f6b4e56d5fb6ef95a7e14c10ec244a79b996 (diff) | |
| download | linux-ac3467ad7f8734a21b65fa1852316a9b1b8c1fad.tar.xz | |
ALSA: hda: ext: fix locking in stream_release
The snd_hdac_ext_stream_release() routine uses the bus reg_lock, but
releases it before calling snd_hdac_stream_release() where the bus
reg_lock is taken again.
This creates a timing window where the link stream release could test
an invalid 'opened' boolean status and fail to recouple the host and
link parts.
Fix by exposing a locked version of snd_hdac_stream_release() and use
it without releasing the spinlock.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Link: https://lore.kernel.org/r/20220919121041.43463-8-pierre-louis.bossart@linux.intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
| -rw-r--r-- | include/sound/hdaudio.h | 1 | ||||
| -rw-r--r-- | sound/hda/ext/hdac_ext_stream.c | 2 | ||||
| -rw-r--r-- | sound/hda/hdac_stream.c | 19 |
3 files changed, 18 insertions, 4 deletions
diff --git a/include/sound/hdaudio.h b/include/sound/hdaudio.h index 35459d740f00..ddff03e546e9 100644 --- a/include/sound/hdaudio.h +++ b/include/sound/hdaudio.h @@ -551,6 +551,7 @@ void snd_hdac_stream_init(struct hdac_bus *bus, struct hdac_stream *azx_dev, int idx, int direction, int tag); struct hdac_stream *snd_hdac_stream_assign(struct hdac_bus *bus, struct snd_pcm_substream *substream); +void snd_hdac_stream_release_locked(struct hdac_stream *azx_dev); void snd_hdac_stream_release(struct hdac_stream *azx_dev); struct hdac_stream *snd_hdac_get_stream(struct hdac_bus *bus, int dir, int stream_tag); diff --git a/sound/hda/ext/hdac_ext_stream.c b/sound/hda/ext/hdac_ext_stream.c index 254df9a67bd2..9a2bc7e803dd 100644 --- a/sound/hda/ext/hdac_ext_stream.c +++ b/sound/hda/ext/hdac_ext_stream.c @@ -384,8 +384,8 @@ void snd_hdac_ext_stream_release(struct hdac_ext_stream *hext_stream, int type) spin_lock_irq(&bus->reg_lock); if (hext_stream->decoupled && !hext_stream->link_locked) snd_hdac_ext_stream_decouple_locked(bus, hext_stream, false); + snd_hdac_stream_release_locked(&hext_stream->hstream); spin_unlock_irq(&bus->reg_lock); - snd_hdac_stream_release(&hext_stream->hstream); break; case HDAC_EXT_STREAM_TYPE_LINK: diff --git a/sound/hda/hdac_stream.c b/sound/hda/hdac_stream.c index c056bcc5543d..1b8be39c38a9 100644 --- a/sound/hda/hdac_stream.c +++ b/sound/hda/hdac_stream.c @@ -366,6 +366,21 @@ struct hdac_stream *snd_hdac_stream_assign(struct hdac_bus *bus, EXPORT_SYMBOL_GPL(snd_hdac_stream_assign); /** + * snd_hdac_stream_release_locked - release the assigned stream + * @azx_dev: HD-audio core stream to release + * + * Release the stream that has been assigned by snd_hdac_stream_assign(). + * The bus->reg_lock needs to be taken at a higher level + */ +void snd_hdac_stream_release_locked(struct hdac_stream *azx_dev) +{ + azx_dev->opened = 0; + azx_dev->running = 0; + azx_dev->substream = NULL; +} +EXPORT_SYMBOL_GPL(snd_hdac_stream_release_locked); + +/** * snd_hdac_stream_release - release the assigned stream * @azx_dev: HD-audio core stream to release * @@ -376,9 +391,7 @@ void snd_hdac_stream_release(struct hdac_stream *azx_dev) struct hdac_bus *bus = azx_dev->bus; spin_lock_irq(&bus->reg_lock); - azx_dev->opened = 0; - azx_dev->running = 0; - azx_dev->substream = NULL; + snd_hdac_stream_release_locked(azx_dev); spin_unlock_irq(&bus->reg_lock); } EXPORT_SYMBOL_GPL(snd_hdac_stream_release); |