From: Ben Dooks ben.dooks@sifive.com
[ Upstream commit 820f5ce999d2f99961e88c16d65cd26764df0590 ]
If the channel has no descriptor and the interrupt is raised then the kernel will OOPS. Check the result of vchan_next_desc() in the handler axi_chan_block_xfer_complete() to avoid the error happening.
Signed-off-by: Ben Dooks ben.dooks@sifive.com Link: https://lore.kernel.org/r/20220708170153.269991-4-ben.dooks@sifive.com Signed-off-by: Vinod Koul vkoul@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c index 8f765e2d7c72..48de8d2b32f2 100644 --- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c +++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c @@ -1016,6 +1016,11 @@ static void axi_chan_block_xfer_complete(struct axi_dma_chan *chan)
/* The completed descriptor currently is in the head of vc list */ vd = vchan_next_desc(&chan->vc); + if (!vd) { + dev_err(chan2dev(chan), "BUG: %s, IRQ with no descriptors\n", + axi_chan_name(chan)); + goto out; + }
if (chan->cyclic) { desc = vd_to_axi_desc(vd); @@ -1045,6 +1050,7 @@ static void axi_chan_block_xfer_complete(struct axi_dma_chan *chan) axi_chan_start_first_queued(chan); }
+out: spin_unlock_irqrestore(&chan->vc.lock, flags); }