This is a note to let you know that I've just added the patch titled dmaengine: mv_xor_v2: handle mv_xor_v2_prep_sw_desc() error properly to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: dmaengine-mv_xor_v2-handle-mv_xor_v2_prep_sw_desc-error-properly.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From eb8df543e444492328f506adffc7dfe94111f1bd Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx> Date: Fri, 5 May 2017 11:57:44 +0200 Subject: dmaengine: mv_xor_v2: handle mv_xor_v2_prep_sw_desc() error properly From: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx> commit eb8df543e444492328f506adffc7dfe94111f1bd upstream. The mv_xor_v2_prep_sw_desc() is called from a few different places in the driver, but we never take into account the fact that it might return NULL. This commit fixes that, ensuring that we don't panic if there are no more descriptors available. Fixes: 19a340b1a820 ("dmaengine: mv_xor_v2: new driver") Signed-off-by: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx> Signed-off-by: Vinod Koul <vinod.koul@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/dma/mv_xor_v2.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/drivers/dma/mv_xor_v2.c +++ b/drivers/dma/mv_xor_v2.c @@ -389,6 +389,8 @@ mv_xor_v2_prep_dma_memcpy(struct dma_cha __func__, len, &src, &dest, flags); sw_desc = mv_xor_v2_prep_sw_desc(xor_dev); + if (!sw_desc) + return NULL; sw_desc->async_tx.flags = flags; @@ -443,6 +445,8 @@ mv_xor_v2_prep_dma_xor(struct dma_chan * __func__, src_cnt, len, &dest, flags); sw_desc = mv_xor_v2_prep_sw_desc(xor_dev); + if (!sw_desc) + return NULL; sw_desc->async_tx.flags = flags; @@ -491,6 +495,8 @@ mv_xor_v2_prep_dma_interrupt(struct dma_ container_of(chan, struct mv_xor_v2_device, dmachan); sw_desc = mv_xor_v2_prep_sw_desc(xor_dev); + if (!sw_desc) + return NULL; /* set the HW descriptor */ hw_descriptor = &sw_desc->hw_desc; Patches currently in stable-queue which might be from thomas.petazzoni@xxxxxxxxxxxxxxxxxx are queue-4.9/dmaengine-mv_xor_v2-properly-handle-wrapping-in-the-array-of-hw-descriptors.patch queue-4.9/dmaengine-mv_xor_v2-enable-xor-engine-after-its-configuration.patch queue-4.9/dmaengine-mv_xor_v2-set-dma-mask-to-40-bits.patch queue-4.9/dmaengine-mv_xor_v2-do-not-use-descriptors-not-acked-by-async_tx.patch queue-4.9/dmaengine-mv_xor_v2-handle-mv_xor_v2_prep_sw_desc-error-properly.patch queue-4.9/dmaengine-mv_xor_v2-remove-interrupt-coalescing.patch queue-4.9/dmaengine-mv_xor_v2-fix-tx_submit-implementation.patch