diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index bebe728019afbec71ec0b5d9cc8e50e49bb0e45d..897940c79a54a1acad9c48bb3190ab3dcc73510c 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -1342,7 +1342,8 @@ static u64 *alloc_pte(struct protection_domain *domain,
 
 			__npte = PM_LEVEL_PDE(level, virt_to_phys(page));
 
-			if (cmpxchg64(pte, __pte, __npte)) {
+			/* pte could have been changed somewhere. */
+			if (cmpxchg64(pte, __pte, __npte) != __pte) {
 				free_page((unsigned long)page);
 				continue;
 			}