[PATCH AUTOSEL 5.2 19/59] ALSA: pcm: fix lost wakeup event scenarios in snd_pcm_drain

From: Sasha Levin
Date: Tue Aug 06 2019 - 17:34:00 EST


From: Yuki Tsunashima <ytsunashima@xxxxxxxxxxxxxx>

[ Upstream commit 37151a41df800493cfcbbef4f7208ffe04feb959 ]

lost wakeup can occur after enabling irq, therefore put task
into interruptible before enabling interrupts,

without this change, task can be put to sleep and snd_pcm_drain
will delay

Fixes: f2b3614cefb6 ("ALSA: PCM - Don't check DMA time-out too shortly")
Signed-off-by: Yuki Tsunashima <ytsunashima@xxxxxxxxxxxxxx>
Signed-off-by: Suresh Udipi <sudipi@xxxxxxxxxxxxxx>
[ported from 4.9]
Signed-off-by: Adam Miartus <amiartus@xxxxxxxxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
sound/core/pcm_native.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index 12dd9b318db18..703857aab00fc 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -1873,6 +1873,7 @@ static int snd_pcm_drain(struct snd_pcm_substream *substream,
if (!to_check)
break; /* all drained */
init_waitqueue_entry(&wait, current);
+ set_current_state(TASK_INTERRUPTIBLE);
add_wait_queue(&to_check->sleep, &wait);
snd_pcm_stream_unlock_irq(substream);
if (runtime->no_period_wakeup)
@@ -1885,7 +1886,7 @@ static int snd_pcm_drain(struct snd_pcm_substream *substream,
}
tout = msecs_to_jiffies(tout * 1000);
}
- tout = schedule_timeout_interruptible(tout);
+ tout = schedule_timeout(tout);

snd_pcm_stream_lock_irq(substream);
group = snd_pcm_stream_group_ref(substream);
--
2.20.1