Currently, an integer is used to specify the size in unmap_sg().
With 2GB worth of pages (512k 4k pages), it requires 31 bits
(i.e. (1 << 19) << 12), which overflows the integer, and ends up
unmapping more pages than intended. Subsequently, this results in
IO_PAGE_FAULT.
Uses size_t instead of int to pass parameter to __unmap_single().
Please note that this patch is only for the stable-kernels tree
because the commit be62dbf554c5 ("iommu/amd: Convert AMD iommu driver
to the dma-iommu api"), which removes the function unmap_sg()
was introduced in v5.5. This patch is not applicable in subsequent
kernel versions.
Cc: stable@xxxxxxxxxxxxxxx
Cc: iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx
Reported-by: Robert Lippert <rlippert@xxxxxxxxxx>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
---
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 32de8e7bb8b4..7adc021932b8 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -2670,7 +2670,7 @@ static void unmap_sg(struct device *dev, struct scatterlist *sglist,
struct protection_domain *domain;
struct dma_ops_domain *dma_dom;
unsigned long startaddr;
- int npages;
+ size_t npages;
domain = get_domain(dev);
if (IS_ERR(domain))
--
2.17.1
