---

yaml
---
r: 230827
b: refs/heads/master
c: fd4a466
h: refs/heads/master
i:
  230825: f14f3ac
  230823: fa216e8
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 1ce82b69e96c838d007f316b8347b911fdfa9842
+refs/heads/master: fd4a4663db293bfd5dc20fb4113977f62895e550

trunk/mm/migrate.c

@@ -827,7 +827,6 @@ static int unmap_and_move_huge_page(new_page_t get_new_page,
 	int rc = 0;
 	int *result = NULL;
 	struct page *new_hpage = get_new_page(hpage, private, &result);
-	int rcu_locked = 0;
 	struct anon_vma *anon_vma = NULL;
 
 	if (!new_hpage)
@@ -842,12 +841,10 @@ static int unmap_and_move_huge_page(new_page_t get_new_page,
 	}
 
 	if (PageAnon(hpage)) {
-		rcu_read_lock();
-		rcu_locked = 1;
-
-		if (page_mapped(hpage)) {
-			anon_vma = page_anon_vma(hpage);
-			atomic_inc(&anon_vma->external_refcount);
+		anon_vma = page_lock_anon_vma(hpage);
+		if (anon_vma) {
+			get_anon_vma(anon_vma);
+			page_unlock_anon_vma(anon_vma);
 		}
 	}
 
@@ -859,16 +856,8 @@ static int unmap_and_move_huge_page(new_page_t get_new_page,
 	if (rc)
 		remove_migration_ptes(hpage, hpage);
 
-	if (anon_vma && atomic_dec_and_lock(&anon_vma->external_refcount,
-					    &anon_vma->lock)) {
-		int empty = list_empty(&anon_vma->head);
-		spin_unlock(&anon_vma->lock);
-		if (empty)
-			anon_vma_free(anon_vma);
-	}
-
-	if (rcu_locked)
-		rcu_read_unlock();
+	if (anon_vma)
+		drop_anon_vma(anon_vma);
 out:
 	unlock_page(hpage);