From 305245a2e1d633e5f821178c98c6d6132cea2bdb Mon Sep 17 00:00:00 2001 From: Basavaraj Natikar Date: Mon, 21 Apr 2025 17:12:15 +0530 Subject: [PATCH] dmaengine: ptdma: Move variable condition check to the first place and remove redundancy The variable is dereferenced without first checking if it's null, leading to the following warning: 'Variable dereferenced before check: desc.' drivers/dma/amd/ptdma/ptdma-dmaengine.c: pt_cmd_callback_work() warn: variable dereferenced before check 'desc' Therefore, move the condition check for the 'desc' variable to the first place and remove the redundant extra condition check. Reported-by: Dan Carpenter Closes: https://lore.kernel.org/all/bfa0a979-ce9f-422d-92c3-34921155d048@stanley.mountain/ Fixes: 656543989457 ("dmaengine: ptdma: Utilize the AE4DMA engine's multi-queue functionality") Signed-off-by: Basavaraj Natikar Link: https://lore.kernel.org/r/20250421114215.1687073-1-Basavaraj.Natikar@amd.com Signed-off-by: Vinod Koul --- drivers/dma/amd/ptdma/ptdma-dmaengine.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/drivers/dma/amd/ptdma/ptdma-dmaengine.c b/drivers/dma/amd/ptdma/ptdma-dmaengine.c index 715ac3ae067b..81339664036f 100644 --- a/drivers/dma/amd/ptdma/ptdma-dmaengine.c +++ b/drivers/dma/amd/ptdma/ptdma-dmaengine.c @@ -342,6 +342,9 @@ static void pt_cmd_callback_work(void *data, int err) struct pt_dma_chan *chan; unsigned long flags; + if (!desc) + return; + dma_chan = desc->vd.tx.chan; chan = to_pt_chan(dma_chan); @@ -355,16 +358,14 @@ static void pt_cmd_callback_work(void *data, int err) desc->status = DMA_ERROR; spin_lock_irqsave(&chan->vc.lock, flags); - if (desc) { - if (desc->status != DMA_COMPLETE) { - if (desc->status != DMA_ERROR) - desc->status = DMA_COMPLETE; + if (desc->status != DMA_COMPLETE) { + if (desc->status != DMA_ERROR) + desc->status = DMA_COMPLETE; - dma_cookie_complete(tx_desc); - dma_descriptor_unmap(tx_desc); - } else { - tx_desc = NULL; - } + dma_cookie_complete(tx_desc); + dma_descriptor_unmap(tx_desc); + } else { + tx_desc = NULL; } spin_unlock_irqrestore(&chan->vc.lock, flags); -- 2.25.1