1 files changed, 10 insertions, 7 deletions

diff --git a/mm/msync.c b/mm/msync.c
index 3b5f1c521d4b..860395486060 100644
--- a/mm/msync.c
+++ b/mm/msync.c
@@ -25,6 +25,7 @@
 static void msync_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
                                 unsigned long addr, unsigned long end)
 {
+        struct mm_struct *mm = vma->vm_mm;
         pte_t *pte;
         int progress = 0;
 
@@ -37,7 +38,7 @@ again:
                 if (progress >= 64) {
                         progress = 0;
                         if (need_resched() ||
-                            need_lockbreak(&vma->vm_mm->page_table_lock))
+                            need_lockbreak(&mm->page_table_lock))
                                 break;
                 }
                 progress++;
@@ -46,11 +47,11 @@ again:
                 if (!pte_maybe_dirty(*pte))
                         continue;
                 pfn = pte_pfn(*pte);
-                if (!pfn_valid(pfn))
+                if (unlikely(!pfn_valid(pfn))) {
+                        print_bad_pte(vma, *pte, addr);
                         continue;
+                }
                 page = pfn_to_page(pfn);
-                if (PageReserved(page))
-                        continue;
 
                 if (ptep_clear_flush_dirty(vma, addr, pte) ||
                     page_test_and_clear_dirty(page))
@@ -58,7 +59,7 @@ again:
                 progress += 3;
         } while (pte++, addr += PAGE_SIZE, addr != end);
         pte_unmap(pte - 1);
-        cond_resched_lock(&vma->vm_mm->page_table_lock);
+        cond_resched_lock(&mm->page_table_lock);
         if (addr != end)
                 goto again;
 }
@@ -102,8 +103,10 @@ static void msync_page_range(struct vm_area_struct *vma,
 
         /* For hugepages we can't go walking the page table normally,
          * but that's ok, hugetlbfs is memory based, so we don't need
-         * to do anything more on an msync() */
-        if (is_vm_hugetlb_page(vma))
+         * to do anything more on an msync().
+         * Can't do anything with VM_RESERVED regions either.
+         */
+        if (vma->vm_flags & (VM_HUGETLB|VM_RESERVED))
                 return;
 
         BUG_ON(addr >= end);