In callback function xdma_prep_device_sg(), it is nice to check if there is zero length segment and skip it in the input scatter list. Reported-by: Martin Tuma <tumic@xxxxxxxxxx> Link: https://lore.kernel.org/dmaengine/f6a0051f-acec-f661-55cb-8b2504bef79e@xxxxxxx/T/#t Signed-off-by: Lizhi Hou <lizhi.hou@xxxxxxx> --- drivers/dma/xilinx/xdma.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/dma/xilinx/xdma.c b/drivers/dma/xilinx/xdma.c index 462109c61653..5134757e88b1 100644 --- a/drivers/dma/xilinx/xdma.c +++ b/drivers/dma/xilinx/xdma.c @@ -465,6 +465,8 @@ xdma_prep_device_sg(struct dma_chan *chan, struct scatterlist *sgl, for_each_sg(sgl, sg, sg_len, i) desc_num += DIV_ROUND_UP(sg_dma_len(sg), XDMA_DESC_BLEN_MAX); + if (!desc_num) + return NULL; sw_desc = xdma_alloc_desc(xdma_chan, desc_num); if (!sw_desc) @@ -488,7 +490,7 @@ xdma_prep_device_sg(struct dma_chan *chan, struct scatterlist *sgl, addr = sg_dma_address(sg); rest = sg_dma_len(sg); - do { + while (rest) { len = min_t(u32, rest, XDMA_DESC_BLEN_MAX); /* set hardware descriptor */ desc->bytes = cpu_to_le32(len); @@ -506,7 +508,7 @@ xdma_prep_device_sg(struct dma_chan *chan, struct scatterlist *sgl, dev_addr += len; addr += len; rest -= len; - } while (rest); + }; } tx_desc = vchan_tx_prep(&xdma_chan->vchan, &sw_desc->vdesc, flags); -- 2.27.0
