diff --git a/hw/i386/amd_iommu.c b/hw/i386/amd_iommu.c
index 74a93a5d93..43b6e9bf51 100644
--- a/hw/i386/amd_iommu.c
+++ b/hw/i386/amd_iommu.c
@@ -860,8 +860,8 @@ static inline uint8_t get_pte_translation_mode(uint64_t pte)
 
 static inline uint64_t pte_override_page_mask(uint64_t pte)
 {
-    uint8_t page_mask = 12;
-    uint64_t addr = (pte & AMDVI_DEV_PT_ROOT_MASK) ^ AMDVI_DEV_PT_ROOT_MASK;
+    uint8_t page_mask = 13;
+    uint64_t addr = (pte & AMDVI_DEV_PT_ROOT_MASK) >> 12;
     /* find the first zero bit */
     while (addr & 1) {
         page_mask++;