From 049c0d577d63c6a95edd5f59fa192f89f2674a64 Mon Sep 17 00:00:00 2001 From: Srikanth Thokala Date: Wed, 5 Nov 2014 20:37:00 +0200 Subject: [PATCH] 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 Signed-off-by: Michal Simek Signed-off-by: Vinod Koul --- drivers/dma/xilinx/xilinx_vdma.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/dma/xilinx/xilinx_vdma.c b/drivers/dma/xilinx/xilinx_vdma.c index a6e64767186e..10937945a527 100644 --- a/drivers/dma/xilinx/xilinx_vdma.c +++ b/drivers/dma/xilinx/xilinx_vdma.c @@ -971,9 +971,11 @@ xilinx_vdma_dma_prep_interleaved(struct dma_chan *dchan, 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); -- 2.39.5