[PATCH v14 12/12] dmaengine: imx-sdma: add terminated list for freed descriptor in worker

[Robin Gong]

On 2021/04/12 17:39,  Vinod Koul <vkoul at kernel.org>  wrote: 
> On 07-04-21, 23:30, Robin Gong wrote:
> > Add terminated list for keeping descriptor so that it could be freed
> > in worker without any potential involving next descriptor raised up
> > before this descriptor freed, because vchan_get_all_descriptors get
> > all descriptors including the last terminated descriptor and the next
> > descriptor, hence, the next descriptor maybe freed unexpectly when
> > it's done in worker without this patch.
> > https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.
> >
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> &rese
> > rved=0
> 
> Sound like you should implement .device_synchronize() and do the actual
> work there..?
Yes,  I believe no issue here if call dmaengine_terminate_sync() always since
flush_work(&sdmac->terminate_worker) has already been in  .device_synchronize() of
sdma driver. But unfortunately, have to use dmaengine_terminate_all() instead in some
non-atomic case like ALSA.