4.9-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit d9c0b2afe820fa3b3f8258a659daee2cc71ca3ef ]
BE dai links only have internal PCM's and their substream ops may not be set. Suspending these PCM's will result in their ops->trigger() being invoked and cause a kernel oops. So skip suspending PCM's if their ops are NULL.
[ NOTE: this change is required now for following the recent PCM core change to get rid of snd_pcm_suspend() call. Since DPCM BE takes the runtime carried from FE while keeping NULL ops, it can hit this bug. See details at: https://github.com/thesofproject/linux/pull/582 -- tiwai ]
Signed-off-by: Ranjani Sridharan ranjani.sridharan@linux.intel.com Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Signed-off-by: Takashi Iwai tiwai@suse.de Signed-off-by: Sasha Levin sashal@kernel.org --- sound/core/pcm_native.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c index e1138e70dbb3..f5eb10f8021c 100644 --- a/sound/core/pcm_native.c +++ b/sound/core/pcm_native.c @@ -1346,6 +1346,14 @@ int snd_pcm_suspend_all(struct snd_pcm *pcm) /* FIXME: the open/close code should lock this as well */ if (substream->runtime == NULL) continue; + + /* + * Skip BE dai link PCM's that are internal and may + * not have their substream ops set. + */ + if (!substream->ops) + continue; + err = snd_pcm_suspend(substream); if (err < 0 && err != -EBUSY) return err;