| Message ID | 1554143899-4124-1-git-send-email-stefan.wahren@i2se.com (mailing list archive) |
|---|---|
| State | Mainlined, archived |
| Commit | f147384774a7b24dda4783a3dcd61af272757ea8 |
| Headers | show |
| Series | [RFC] dmaengine: bcm2835: Avoid GFP_KERNEL in device_prep_slave_sg | expand |
On 01-04-19, 20:38, Stefan Wahren wrote: > The commit af19b7ce76ba ("mmc: bcm2835: Avoid possible races on > data requests") introduces a possible circular locking dependency, > which is triggered by swapping to the sdhost interface. > > So instead of reintroduce the race condition again, we could also > avoid this situation by using GFP_NOWAIT for the allocation of the > DMA buffer descriptors. Applied, thanks
diff --git a/drivers/dma/bcm2835-dma.c b/drivers/dma/bcm2835-dma.c index ec8a291..54093ff 100644 --- a/drivers/dma/bcm2835-dma.c +++ b/drivers/dma/bcm2835-dma.c @@ -671,7 +671,7 @@ static struct dma_async_tx_descriptor *bcm2835_dma_prep_slave_sg( d = bcm2835_dma_create_cb_chain(chan, direction, false, info, extra, frames, src, dst, 0, 0, - GFP_KERNEL); + GFP_NOWAIT); if (!d) return NULL;
The commit af19b7ce76ba ("mmc: bcm2835: Avoid possible races on data requests") introduces a possible circular locking dependency, which is triggered by swapping to the sdhost interface. So instead of reintroduce the race condition again, we could also avoid this situation by using GFP_NOWAIT for the allocation of the DMA buffer descriptors. Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi> Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> Fixes: af19b7ce76ba ("mmc: bcm2835: Avoid possible races on data requests") Link: http://lists.infradead.org/pipermail/linux-rpi-kernel/2019-March/008615.html --- drivers/dma/bcm2835-dma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)