From 42e67b479eab6d26459b80b4867298232b0435e7 Mon Sep 17 00:00:00 2001 From: Shane Francis Date: Wed, 25 Mar 2020 09:07:39 +0000 Subject: [PATCH] drm/prime: use dma length macro when mapping sg As dma_map_sg can reorganize scatter-gather lists in a way that can cause some later segments to be empty we should always use the sg_dma_len macro to fetch the actual length. This could now be 0 and not need to be mapped to a page or address array Fixes: be62dbf554c5 ("iommu/amd: Convert AMD iommu driver to the dma-iommu api") Bug: https://bugzilla.kernel.org/show_bug.cgi?id=206461 Bug: https://bugzilla.kernel.org/show_bug.cgi?id=206895 Bug: https://gitlab.freedesktop.org/drm/amd/issues/1056 Signed-off-by: Shane Francis Reviewed-by: Michael J. Ruhl Signed-off-by: Alex Deucher Link: https://patchwork.freedesktop.org/patch/msgid/20200325090741.21957-2-bigbeeshane@gmail.com Cc: stable@vger.kernel.org --- drivers/gpu/drm/drm_prime.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c index 86d9b0e..1de2cde 100644 --- a/drivers/gpu/drm/drm_prime.c +++ b/drivers/gpu/drm/drm_prime.c @@ -967,7 +967,7 @@ int drm_prime_sg_to_page_addr_arrays(struct sg_table *sgt, struct page **pages, index = 0; for_each_sg(sgt->sgl, sg, sgt->nents, count) { - len = sg->length; + len = sg_dma_len(sg); page = sg_page(sg); addr = sg_dma_address(sg); -- 2.7.4