ASoC: samsung: Use IRQ safe spin lock calls

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[ Upstream commit 316fa9e09a ]

Lockdep warns of a potential lock inversion, i2s->lock is held numerous
times whilst we are under the substream lock (snd_pcm_stream_lock). If
we use the IRQ unsafe spin lock calls, you can also end up locking
snd_pcm_stream_lock whilst under i2s->lock (if an IRQ happens whilst we
are holding i2s->lock). This could result in deadlock.

[   18.147001]        CPU0                    CPU1
[   18.151509]        ----                    ----
[   18.156022]   lock(&(&pri_dai->spinlock)->rlock);
[   18.160701]                                local_irq_disable();
[   18.166622]                                lock(&(&substream->self_group.lock)->rlock);
[   18.174595]                                lock(&(&pri_dai->spinlock)->rlock);
[   18.181806]   <Interrupt>
[   18.184408]     lock(&(&substream->self_group.lock)->rlock);
[   18.190045]
[   18.190045]  *** DEADLOCK ***

This patch changes to using the irq safe spinlock calls, to avoid this
issue.

Fixes: ce8bcdbb61 ("ASoC: samsung: i2s: Protect more registers with a spinlock")
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Tested-by: Anand Moon <linux.amoon@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

...

This commit is contained in:

Charles Keepax 2016-02-18 15:47:13 +00:00 • committed by Sasha Levin

parent 7e62b96835

commit ea46df70ef

1 changed files with 12 additions and 9 deletions

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sound/soc/samsung/i2s.c

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