Merge tag 'v3.10.78' into update

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / mm / mremap.c

diff --git a/mm/mremap.c b/mm/mremap.c
index 463a25705ac6d4ca38fb202b30b2ccae9161ce5b..2201d060c31b2ed423da899c6d57bea596df2981 100644 (file)
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -175,10 +175,17 @@ unsigned long move_page_tables(struct vm_area_struct *vma,
                        break;
                if (pmd_trans_huge(*old_pmd)) {
                        int err = 0;
-                       if (extent == HPAGE_PMD_SIZE)
+                       if (extent == HPAGE_PMD_SIZE) {
+                               VM_BUG_ON(vma->vm_file || !vma->anon_vma);
+                               /* See comment in move_ptes() */
+                               if (need_rmap_locks)
+                                       anon_vma_lock_write(vma->anon_vma);
                                err = move_huge_pmd(vma, new_vma, old_addr,
                                                    new_addr, old_end,
                                                    old_pmd, new_pmd);
+                               if (need_rmap_locks)
+                                       anon_vma_unlock_write(vma->anon_vma);
+                       }
                        if (err > 0) {
                                need_flush = true;
                                continue;