4.11-stable review patch. If anyone has any objections, please let me know.
------------------
From: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx>
commit eb8df543e444492328f506adffc7dfe94111f1bd upstream.
The mv_xor_v2_prep_sw_desc() is called from a few different places in
the driver, but we never take into account the fact that it might
return NULL. This commit fixes that, ensuring that we don't panic if
there are no more descriptors available.
Fixes: 19a340b1a820 ("dmaengine: mv_xor_v2: new driver")
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Vinod Koul <vinod.koul@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/dma/mv_xor_v2.c | 6 ++++++
1 file changed, 6 insertions(+)
--- a/drivers/dma/mv_xor_v2.c
+++ b/drivers/dma/mv_xor_v2.c
@@ -389,6 +389,8 @@ mv_xor_v2_prep_dma_memcpy(struct dma_cha
__func__, len, &src, &dest, flags);
sw_desc = mv_xor_v2_prep_sw_desc(xor_dev);
+ if (!sw_desc)
+ return NULL;
sw_desc->async_tx.flags = flags;
@@ -443,6 +445,8 @@ mv_xor_v2_prep_dma_xor(struct dma_chan *
__func__, src_cnt, len, &dest, flags);
sw_desc = mv_xor_v2_prep_sw_desc(xor_dev);
+ if (!sw_desc)
+ return NULL;
sw_desc->async_tx.flags = flags;
@@ -491,6 +495,8 @@ mv_xor_v2_prep_dma_interrupt(struct dma_
container_of(chan, struct mv_xor_v2_device, dmachan);
sw_desc = mv_xor_v2_prep_sw_desc(xor_dev);
+ if (!sw_desc)
+ return NULL;
/* set the HW descriptor */
hw_descriptor = &sw_desc->hw_desc;