Hi, With the help of a static bug finder (EBA - http://www.iagoabal.eu/eba/) I have found a potential double-lock in drivers/dma/pl330.c. This happens due to a recursive spin_lock_irqsave on `pch->lock'. If this is indeed a bug, I will be happy to help with a patch. The trace is as follows: 1. Function `pl330_free_chan_resources' takes the lock for the first time in line 2236: // https://github.com/torvalds/linux/blob/v4.10-rc2/drivers/dma/pl330.c#L2236 spin_lock_irqsave(&pch->lock, flags); 2. Call to function `pl330_release_channel' immediately after; 3. Call to function `dma_pl330_rqcb' in line 1753; 4. Assuming that pch->thread->req[i].desc->pchan == pch, then function `dma_pl330_rqcb' takes the lock again in line 1505: // https://github.com/torvalds/linux/blob/v4.10-rc2/drivers/dma/pl330.c#L1505 spin_lock_irqsave(&pch->lock, flags); Hope it helps! -- iago -- 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
