diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index be3801d43d48b4c779759ca500d686827be757cd..3a1d30304f7e9167a0a448b8132b5c93a535abff 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -356,7 +356,7 @@ static void iommu_write_l2(struct amd_iommu *iommu, u8 address, u32 val)
 static void iommu_set_exclusion_range(struct amd_iommu *iommu)
 {
 	u64 start = iommu->exclusion_start & PAGE_MASK;
-	u64 limit = (start + iommu->exclusion_length) & PAGE_MASK;
+	u64 limit = (start + iommu->exclusion_length - 1) & PAGE_MASK;
 	u64 entry;
 
 	if (!iommu->exclusion_start)