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author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-02-19 16:01:41 (GMT) |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-02-19 16:01:41 (GMT) |
commit | 9001b8e4f08dd7ae8429214979bd7783160932c5 (patch) | |
tree | 38a3babfeb313d2572f45ff4c4607dc7d5dccd80 | |
parent | 705d43dbe10d6e213a75187ac92b61f9bd00af0b (diff) | |
parent | 67ec1072b053c15564e6090ab30127895dc77a89 (diff) | |
download | linux-9001b8e4f08dd7ae8429214979bd7783160932c5.tar.xz |
Merge tag 'sound-4.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"This update contains again a few more fixes for ALSA core stuff
although it's no longer high flux: two race fixes in sequencer and one
PCM race fix for non-atomic PCM ops.
In addition, HD-audio gained a similar fix for race at reloading the
driver"
* tag 'sound-4.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: pcm: Fix rwsem deadlock for non-atomic PCM stream
ALSA: seq: Fix double port list deletion
ALSA: hda - Cancel probe work instead of flush at remove
ALSA: seq: Fix leak of pool buffer at concurrent writes
-rw-r--r-- | sound/core/pcm_native.c | 16 | ||||
-rw-r--r-- | sound/core/seq/seq_memory.c | 13 | ||||
-rw-r--r-- | sound/core/seq/seq_ports.c | 13 | ||||
-rw-r--r-- | sound/pci/hda/hda_intel.c | 4 |
4 files changed, 33 insertions, 13 deletions
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c index fadd3eb..9106d8e 100644 --- a/sound/core/pcm_native.c +++ b/sound/core/pcm_native.c @@ -74,6 +74,18 @@ static int snd_pcm_open(struct file *file, struct snd_pcm *pcm, int stream); static DEFINE_RWLOCK(snd_pcm_link_rwlock); static DECLARE_RWSEM(snd_pcm_link_rwsem); +/* Writer in rwsem may block readers even during its waiting in queue, + * and this may lead to a deadlock when the code path takes read sem + * twice (e.g. one in snd_pcm_action_nonatomic() and another in + * snd_pcm_stream_lock()). As a (suboptimal) workaround, let writer to + * spin until it gets the lock. + */ +static inline void down_write_nonblock(struct rw_semaphore *lock) +{ + while (!down_write_trylock(lock)) + cond_resched(); +} + /** * snd_pcm_stream_lock - Lock the PCM stream * @substream: PCM substream @@ -1813,7 +1825,7 @@ static int snd_pcm_link(struct snd_pcm_substream *substream, int fd) res = -ENOMEM; goto _nolock; } - down_write(&snd_pcm_link_rwsem); + down_write_nonblock(&snd_pcm_link_rwsem); write_lock_irq(&snd_pcm_link_rwlock); if (substream->runtime->status->state == SNDRV_PCM_STATE_OPEN || substream->runtime->status->state != substream1->runtime->status->state || @@ -1860,7 +1872,7 @@ static int snd_pcm_unlink(struct snd_pcm_substream *substream) struct snd_pcm_substream *s; int res = 0; - down_write(&snd_pcm_link_rwsem); + down_write_nonblock(&snd_pcm_link_rwsem); write_lock_irq(&snd_pcm_link_rwlock); if (!snd_pcm_stream_linked(substream)) { res = -EALREADY; diff --git a/sound/core/seq/seq_memory.c b/sound/core/seq/seq_memory.c index 8010766..c850345 100644 --- a/sound/core/seq/seq_memory.c +++ b/sound/core/seq/seq_memory.c @@ -383,15 +383,20 @@ int snd_seq_pool_init(struct snd_seq_pool *pool) if (snd_BUG_ON(!pool)) return -EINVAL; - if (pool->ptr) /* should be atomic? */ - return 0; - pool->ptr = vmalloc(sizeof(struct snd_seq_event_cell) * pool->size); - if (!pool->ptr) + cellptr = vmalloc(sizeof(struct snd_seq_event_cell) * pool->size); + if (!cellptr) return -ENOMEM; /* add new cells to the free cell list */ spin_lock_irqsave(&pool->lock, flags); + if (pool->ptr) { + spin_unlock_irqrestore(&pool->lock, flags); + vfree(cellptr); + return 0; + } + + pool->ptr = cellptr; pool->free = NULL; for (cell = 0; cell < pool->size; cell++) { diff --git a/sound/core/seq/seq_ports.c b/sound/core/seq/seq_ports.c index 921fb2b..fe686ee 100644 --- a/sound/core/seq/seq_ports.c +++ b/sound/core/seq/seq_ports.c @@ -535,19 +535,22 @@ static void delete_and_unsubscribe_port(struct snd_seq_client *client, bool is_src, bool ack) { struct snd_seq_port_subs_info *grp; + struct list_head *list; + bool empty; grp = is_src ? &port->c_src : &port->c_dest; + list = is_src ? &subs->src_list : &subs->dest_list; down_write(&grp->list_mutex); write_lock_irq(&grp->list_lock); - if (is_src) - list_del(&subs->src_list); - else - list_del(&subs->dest_list); + empty = list_empty(list); + if (!empty) + list_del_init(list); grp->exclusive = 0; write_unlock_irq(&grp->list_lock); up_write(&grp->list_mutex); - unsubscribe_port(client, port, grp, &subs->info, ack); + if (!empty) + unsubscribe_port(client, port, grp, &subs->info, ack); } /* connect two ports */ diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c index 4045dca..ce6b97f 100644 --- a/sound/pci/hda/hda_intel.c +++ b/sound/pci/hda/hda_intel.c @@ -2168,10 +2168,10 @@ static void azx_remove(struct pci_dev *pci) struct hda_intel *hda; if (card) { - /* flush the pending probing work */ + /* cancel the pending probing work */ chip = card->private_data; hda = container_of(chip, struct hda_intel, chip); - flush_work(&hda->probe_work); + cancel_work_sync(&hda->probe_work); snd_card_free(card); } |