The function uses chip->comm_page which needs locking against other use at the same time. Signed-off-by: Mark Hills <mark@xxxxxxxx> --- sound/pci/echoaudio/echoaudio.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/sound/pci/echoaudio/echoaudio.c b/sound/pci/echoaudio/echoaudio.c index 82a49dfd2384..8cf08988959f 100644 --- a/sound/pci/echoaudio/echoaudio.c +++ b/sound/pci/echoaudio/echoaudio.c @@ -711,9 +711,22 @@ static int pcm_prepare(struct snd_pcm_substream *substream) if (snd_BUG_ON(pipe_index >= px_num(chip))) return -EINVAL; - if (snd_BUG_ON(!is_pipe_allocated(chip, pipe_index))) + + /* + * We passed checks we can do independently; now take + * exclusive control + */ + + spin_lock(&chip->lock); + + if (snd_BUG_ON(!is_pipe_allocated(chip, pipe_index))) { + spin_unlock(&chip->lock); return -EINVAL; + } + set_audio_format(chip, pipe_index, &format); + spin_unlock(&chip->lock); + return 0; } -- 2.17.5