1 files changed, 9 insertions, 0 deletions

diff --git a/mm/mremap.c b/mm/mremap.c
index d6959cb4df58..87bb8393e7d2 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -221,6 +221,15 @@ static unsigned long move_vma(struct vm_area_struct *vma,
         moved_len = move_page_tables(vma, old_addr, new_vma, new_addr, old_len);
         if (moved_len < old_len) {
                 /*
+                 * Before moving the page tables from the new vma to
+                 * the old vma, we need to be sure the old vma is
+                 * queued after new vma in the same_anon_vma list to
+                 * prevent SMP races with rmap_walk (that could lead
+                 * rmap_walk to miss some page table).
+                 */
+                anon_vma_moveto_tail(vma);
+
+                /*
                  * On error, move entries back from new area to old,
                  * which will succeed since page tables still there,
                  * and then proceed to unmap new area instead of old.