Commit 58152b0e authored May 06, 2019 by Baolin Wang Committed by Vinod Koul May 21, 2019

dmaengine: sprd: Add validation of current descriptor in irq handler



When user terminates one DMA channel to free all its descriptors, but
at the same time one transaction interrupt was triggered possibly, now
we should not handle this interrupt by validating if the 'schan->cur_desc'
was set as NULL to avoid crashing the kernel.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>

parent 16d0f85e

drivers/dma/sprd-dma.c

+7 −2

Original line number	Diff line number	Diff line
		@@ -552,12 +552,17 @@ static irqreturn_t dma_irq_handle(int irq, void *dev_id)
		schan = &sdev->channels[i];

		spin_lock(&schan->vc.lock);

		sdesc = schan->cur_desc;
		if (!sdesc) {
		spin_unlock(&schan->vc.lock);
		return IRQ_HANDLED;
		}

		int_type = sprd_dma_get_int_type(schan);
		req_type = sprd_dma_get_req_type(schan);
		sprd_dma_clear_int(schan);

		sdesc = schan->cur_desc;

		/* cyclic mode schedule callback */
		cyclic = schan->linklist.phy_addr ? true : false;
		if (cyclic == true) {

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