This is a note to let you know that I've just added the patch titled net: ipa: pass the correct size when freeing DMA memory to the 5.9-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: net-ipa-pass-the-correct-size-when-freeing-dma-memory.patch and it can be found in the queue-5.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Sat Dec 19 11:38:43 AM CET 2020 From: Alex Elder <elder@xxxxxxxxxx> Date: Thu, 3 Dec 2020 15:51:06 -0600 Subject: net: ipa: pass the correct size when freeing DMA memory From: Alex Elder <elder@xxxxxxxxxx> [ Upstream commit 1130b252480f3c98cf468e78c1c5c516b390a29c ] When the coherent memory is freed in gsi_trans_pool_exit_dma(), we are mistakenly passing the size of a single element in the pool rather than the actual allocated size. Fix this bug. Fixes: 9dd441e4ed575 ("soc: qcom: ipa: GSI transactions") Reported-by: Stephen Boyd <swboyd@xxxxxxxxxxxx> Tested-by: Sujit Kautkar <sujitka@xxxxxxxxxxxx> Signed-off-by: Alex Elder <elder@xxxxxxxxxx> Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> Link: https://lore.kernel.org/r/20201203215106.17450-1-elder@xxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ipa/gsi_trans.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/drivers/net/ipa/gsi_trans.c +++ b/drivers/net/ipa/gsi_trans.c @@ -157,6 +157,9 @@ int gsi_trans_pool_init_dma(struct devic /* The allocator will give us a power-of-2 number of pages. But we * can't guarantee that, so request it. That way we won't waste any * memory that would be available beyond the required space. + * + * Note that gsi_trans_pool_exit_dma() assumes the total allocated + * size is exactly (count * size). */ total_size = get_order(total_size) << PAGE_SHIFT; @@ -176,7 +179,9 @@ int gsi_trans_pool_init_dma(struct devic void gsi_trans_pool_exit_dma(struct device *dev, struct gsi_trans_pool *pool) { - dma_free_coherent(dev, pool->size, pool->base, pool->addr); + size_t total_size = pool->count * pool->size; + + dma_free_coherent(dev, total_size, pool->base, pool->addr); memset(pool, 0, sizeof(*pool)); } Patches currently in stable-queue which might be from elder@xxxxxxxxxx are queue-5.9/net-ipa-pass-the-correct-size-when-freeing-dma-memory.patch