Re: ASoC q6asm race condition when stopping and preparing the stream

[Alexey Klimov]

On Fri May 1, 2026 at 3:41 PM BST, Richard Acayan wrote:
> Hi,
>
> There seems to be a race condition in q6asm when stopping the stream
> (with uncompressed PCM). When receiving SNDRV_PCM_TRIGGER_STOP, the
> driver sets the state to Q6ASM_STREAM_STOPPED and sends CMD_EOS to the
> ADSP. If userspace decides to prepare the stream again in
> q6asm_dai_prepare before receiving ASM_CLIENT_EVENT_CMD_EOS_DONE, the
> memory-mapped region appears to still be in use and fails to map again.
>
> I believe this race was observed since commit 81c53b52de21 ("ASoC: qcom:
> qdsp6: q6asm-dai: set 10 ms period and buffer alignment."), but would
> need to verify. On sdm670, we are coping downstream by keeping the state
> as Q6ASM_STREAM_RUNNING until receiving CMD_EOS_DONE.

Do you have a reproducer or specific steps to test/reproduce the issue?


> Can the ADSP emit DATA_WRITE_DONE or DATA_READ_DONE before CMD_EOS_DONE?
> We might need an extra stopping state between CMD_EOS and CMD_EOS_DONE
> so the driver doesn't request more data transfers.

Thanks,
Alexey