1 files changed, 5 insertions, 3 deletions

diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 6e27979506c1..21058ad1e5e3 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -1488,10 +1488,12 @@ static __init pte_t mask_rw_pte(pte_t *ptep, pte_t pte)
         /*
          * If the new pfn is within the range of the newly allocated
          * kernel pagetable, and it isn't being mapped into an
-         * early_ioremap fixmap slot, make sure it is RO.
+         * early_ioremap fixmap slot as a freshly allocated page, make sure
+         * it is RO.
          */
-        if (!is_early_ioremap_ptep(ptep) &&
-            pfn >= pgt_buf_start && pfn < pgt_buf_end)
+        if (((!is_early_ioremap_ptep(ptep) &&
+                        pfn >= pgt_buf_start && pfn < pgt_buf_end)) ||
+                        (is_early_ioremap_ptep(ptep) && pfn != (pgt_buf_end - 1)))
                 pte = pte_wrprotect(pte);
 
         return pte;