[RFC 2/3] dmaengine: omap-dma: Prevent race between vchan_complete() and terminate_all

[Peter Ujfalusi]

Implement protection against vchan_complete() calling the client callback
after the channel has been terminated.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
---
 drivers/dma/omap-dma.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c
index bfdf29aa3428..1912be81e56d 100644
--- a/drivers/dma/omap-dma.c
+++ b/drivers/dma/omap-dma.c
@@ -980,7 +980,9 @@ static int omap_dma_terminate_all(struct dma_chan *chan)
 	unsigned long flags;
 	LIST_HEAD(head);
 
+	tasklet_disable(&c->vc.task);
 	spin_lock_irqsave(&c->vc.lock, flags);
+	vchan_terminate(&c->vc);
 
 	/*
 	 * Stop DMA activity: we assume the callback will not be called
@@ -1003,6 +1005,7 @@ static int omap_dma_terminate_all(struct dma_chan *chan)
 	vchan_get_all_descriptors(&c->vc, &head);
 	spin_unlock_irqrestore(&c->vc.lock, flags);
 	vchan_dma_desc_free_list(&c->vc, &head);
+	tasklet_enable(&c->vc.task);
 
 	return 0;
 }
-- 
2.7.1


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