1 files changed, 6 insertions, 1 deletions

diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 5f76c0acb2c..d957dce61ed 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -320,8 +320,13 @@ static pteval_t pte_mfn_to_pfn(pteval_t val)
 {
         if (val & _PAGE_PRESENT) {
                 unsigned long mfn = (val & PTE_PFN_MASK) >> PAGE_SHIFT;
+                unsigned long pfn = mfn_to_pfn(mfn);
+
                 pteval_t flags = val & PTE_FLAGS_MASK;
-                val = ((pteval_t)mfn_to_pfn(mfn) << PAGE_SHIFT) | flags;
+                if (unlikely(pfn == ~0))
+                        val = flags & ~_PAGE_PRESENT;
+                else
+                        val = ((pteval_t)pfn << PAGE_SHIFT) | flags;
         }
 
         return val;