From 58152b0e573e5581c4b9ef7cf06d2e9fafae27d4 Mon Sep 17 00:00:00 2001 From: Baolin Wang Date: Mon, 6 May 2019 15:28:29 +0800 Subject: 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 Signed-off-by: Vinod Koul --- drivers/dma/sprd-dma.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'drivers/dma/sprd-dma.c') diff --git a/drivers/dma/sprd-dma.c b/drivers/dma/sprd-dma.c index e29342ab85f6..431e289d59a5 100644 --- a/drivers/dma/sprd-dma.c +++ b/drivers/dma/sprd-dma.c @@ -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) { -- cgit v1.2.3