From eb8df543e444492328f506adffc7dfe94111f1bd Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Fri, 5 May 2017 11:57:44 +0200 Subject: [PATCH] dmaengine: mv_xor_v2: handle mv_xor_v2_prep_sw_desc() error properly 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") Cc: Signed-off-by: Thomas Petazzoni Signed-off-by: Vinod Koul --- drivers/dma/mv_xor_v2.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/dma/mv_xor_v2.c b/drivers/dma/mv_xor_v2.c index a28a01fcba67..e9280207ac19 100644 --- 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_chan *chan, dma_addr_t dest, __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 *chan, dma_addr_t dest, dma_addr_t *src, __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_chan *chan, unsigned long flags) 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; -- 2.20.1