1 files changed, 5 insertions, 1 deletions
diff --git a/mm/mmap.c b/mm/mmap.c
index 2ba27434e84..e3c365ff1b6 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -573,8 +573,12 @@ again:			remove_next = 1 + (end > next->vm_end);
         */
        if (vma->anon_vma && (importer || start != vma->vm_start)) {
                anon_vma = vma->anon_vma;
+                VM_BUG_ON(adjust_next && next->anon_vma &&
+                          anon_vma != next->anon_vma);
+        } else if (adjust_next && next->anon_vma)
+                anon_vma = next->anon_vma;
+        if (anon_vma)
                anon_vma_lock(anon_vma);
-        }
        if (root) {
                flush_dcache_mmap_lock(mapping);