From 0dce3b5433da970739d3e0407c577895e4829ccd Mon Sep 17 00:00:00 2001 From: Ranjani Sridharan Date: Fri, 8 Feb 2019 17:29:53 -0600 Subject: [PATCH] ALSA: PCM: check if ops are defined before suspending PCM 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 Signed-off-by: Pierre-Louis Bossart Signed-off-by: Takashi Iwai (cherry picked from commit d9c0b2afe820fa3b3f8258a659daee2cc71ca3ef) (cherry picked from commit 1bde5ed6fa67c1ee48fa59d257f860fb290b33e3) --- 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 818dff1de545..b6e158ce6650 100644 --- a/sound/core/pcm_native.c +++ b/sound/core/pcm_native.c @@ -1506,6 +1506,14 @@ 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;