overlayfs: fix lockdep misannotation

In an overlay directory that shadows an empty lower directory, say
/mnt/a/empty102, do:

 	touch /mnt/a/empty102/x
 	unlink /mnt/a/empty102/x
 	rmdir /mnt/a/empty102

It's actually harmless, but needs another level of nesting between
I_MUTEX_CHILD and I_MUTEX_NORMAL.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/namei.c b/fs/namei.c
index 42df664e95e5..922f27068c4c 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2497,7 +2497,7 @@ struct dentry *lock_rename(struct dentry *p1, struct dentry *p2)
         }
 
         mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT);
-        mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_CHILD);
+        mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_PARENT2);
         return NULL;
 }
 EXPORT_SYMBOL(lock_rename);