Hi,
I seeing sometimes deadlock issue with dmix when I press CTRL+C.
Aplay's signal handler calls snd_pcm_close() if an interrupt occurs. snd_pcm_close() will internally call pcm->ops->close() which will fall to snd_pcm_dmix_close() in case you are using dmix.
snd_pcm_dmix_close() will try to acquire the semaphore with snd_pcm_direct_semaphore_down(dmix, DIRECT_IPC_SEM_CLIENT). The same semaphore is acquired in snd_pcm_dmix_sync_area() with dmix_down_sem() in case of non-concurrent access.
If semaphore is acquired in snd_pcm_dmix_sync_area() which is in thread context and interrupt comes, which invokes the signal handler which is in ISR context, which calls snd_pcm_close() which in turn calls snd_pcm_dmix_close() then we see a deadlock since semaphore is not released from thread context and ISR is waiting indefinitely on the same semaphore.
Please suggest a suitable solution for this.