4.20-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit f1724c0883bb0ce93b8dcb94b53dcca3b75ac9a7 ]
In the error path of map_sg there is an incorrect if condition for breaking out of the loop that searches the scatterlist for mapped pages to unmap. Instead of breaking out of the loop once all the pages that were mapped have been unmapped, it will break out of the loop after it has unmapped 1 page. Fix the condition, so it breaks out of the loop only after all the mapped pages have been unmapped.
Fixes: 80187fd39dcb ("iommu/amd: Optimize map_sg and unmap_sg") Cc: Joerg Roedel joro@8bytes.org Signed-off-by: Jerry Snitselaar jsnitsel@redhat.com Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/iommu/amd_iommu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index 5f33f843d30a..ca3a250d8fa7 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -2555,7 +2555,7 @@ static int map_sg(struct device *dev, struct scatterlist *sglist, bus_addr = address + s->dma_address + (j << PAGE_SHIFT); iommu_unmap_page(domain, bus_addr, PAGE_SIZE);
- if (--mapped_pages) + if (--mapped_pages == 0) goto out_free_iova; } }