[PATCH 1/2] 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 <redacted>
---
 drivers/dma/nbpfaxi.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/dma/nbpfaxi.c b/drivers/dma/nbpfaxi.c
index 77c5a89..5b40ac8 100644
--- a/drivers/dma/nbpfaxi.c
+++ b/drivers/dma/nbpfaxi.c

@@ -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);
 

-- 
1.9.3

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