On 26 September 2015 at 05:38, yitian <yitian.bu@xxxxxxxxxxxxxx> wrote: > when audio playback is running, user space will call > snd_pcm_lib_write1() function, it will first get pcm stream lock, > after that it may call function snd_pcm_update_hw_ptr(), the call > stack will be as below: > snd_pcm_lib_write1 <-- got pcm stream lock > --> snd_pcm_update_hw_ptr > --> dwc_tx_status > --> dwc_scan_descriptors > --> callback > --> dmaengine_pcm_dma_complete > --> snd_pcm_period_elapsed <-- get stream lock again > recursion lock occurs in snd_pcm_period_elapsed function. > remove dwc_scan_descriptors from dwc_tx_status can fix this issue. > > Signed-off-by: Yitian Bu <yitian.bu@xxxxxxxxxxxxxx> > --- > drivers/dma/dw/core.c | 6 +----- > 1 file changed, 1 insertion(+), 5 deletions(-) I am not sure if this is a sane way of doing that, and we were scanning the descriptors for some valid reason.. Though, I am on vacation for few days now and will be able to look at the details later. -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
