diff --git a/fs/ext2/ext2.h b/fs/ext2/ext2.h
index 690452808d24..2ace014ed43c 100644
--- a/fs/ext2/ext2.h
+++ b/fs/ext2/ext2.h
@@ -761,7 +761,8 @@ extern __printf(3, 4)
 void ext2_error(struct super_block *, const char *, const char *, ...);
 extern __printf(3, 4)
 void ext2_msg(struct super_block *, const char *, const char *, ...);
-extern void ext2_update_dynamic_rev (struct super_block *sb);
+extern void ext2_update_dynamic_rev(struct super_block *sb)
+	__must_hold(&EXT2_SB(sb)->s_lock);
 extern void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
 			    int wait);
 
diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index 3d64b28745d3..27f32637d1b8 100644
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -127,6 +127,7 @@ void ext2_msg(struct super_block *sb, const char *prefix,
  * This must be called with sbi->s_lock held.
  */
 void ext2_update_dynamic_rev(struct super_block *sb)
+	__must_hold(&EXT2_SB(sb)->s_lock)
 {
 	struct ext2_super_block *es = EXT2_SB(sb)->s_es;