[PATCH] iommu/arm-smmu-v3: Fix undefined behavior in GBPA_UPDATE

Xenia Ragiadakou burzalodowa at gmail.com
Wed Jun 29 23:39:59 PDT 2022


The expression 1 << 31 results in undefined behaviour because the type of
integer constant 1 is (signed) int and the result of shifting 1 by 31 bits
is not representable in the (signed) int type.

Change the type of 1 to unsigned int by adding the U suffix.

Signed-off-by: Xenia Ragiadakou <burzalodowa at gmail.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
index cd48590ada30..44fbd499edea 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -96,7 +96,7 @@
 #define CR2_E2H				(1 << 0)
 
 #define ARM_SMMU_GBPA			0x44
-#define GBPA_UPDATE			(1 << 31)
+#define GBPA_UPDATE			(1U << 31)
 #define GBPA_ABORT			(1 << 20)
 
 #define ARM_SMMU_IRQ_CTRL		0x50
-- 
2.34.1




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