dmaengine: nbpfaxi: fix a theoretical race

A race possibility exists if a DMA slave driver tries to free channel
resources witout waiting for all transfers to complete and without
explicitly terminating all requests. In such a case the IRQ processing
thread can race with .device_free_chan_resources(). To fix this race empty
all descriptor lists before freeing descriptor cache.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This commit is contained in:
Guennadi Liakhovetski 2014-08-03 19:13:03 +02:00 committed by Vinod Koul
parent b45b262cef
commit 67b1668470

View file

@ -1054,6 +1054,7 @@ static void nbpf_free_chan_resources(struct dma_chan *dchan)
dev_dbg(dchan->device->dev, "Entry %s()\n", __func__);
nbpf_chan_halt(chan);
nbpf_chan_idle(chan);
/* Clean up for if a channel is re-used for MEMCPY after slave DMA */
nbpf_chan_prepare_default(chan);