dmaengine: xilinx: vdma: Check if the segment list is empty in a descriptor
The segment list in a descriptor should be checked for empty, else
it will try to access invalid address for the first call. This
patch fixes this issue.
Signed-off-by: Srikanth Thokala <sthokal@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
diff --git a/drivers/dma/xilinx/xilinx_vdma.c b/drivers/dma/xilinx/xilinx_vdma.c
index a6e6476..1093794 100644
--- a/drivers/dma/xilinx/xilinx_vdma.c
+++ b/drivers/dma/xilinx/xilinx_vdma.c
@@ -971,9 +971,11 @@
hw->buf_addr = xt->src_start;
/* Link the previous next descriptor to current */
- prev = list_last_entry(&desc->segments,
- struct xilinx_vdma_tx_segment, node);
- prev->hw.next_desc = segment->phys;
+ if (!list_empty(&desc->segments)) {
+ prev = list_last_entry(&desc->segments,
+ struct xilinx_vdma_tx_segment, node);
+ prev->hw.next_desc = segment->phys;
+ }
/* Insert the segment into the descriptor segments list. */
list_add_tail(&segment->node, &desc->segments);