diff --git a/[refs] b/[refs]
index 7d16cfffa40b..de19730520d7 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: b5fb63c18315c5510c1d0636179c057e0c761c77
+refs/heads/master: c4107b3097465e25f7d6a9b0ac0518b07b24e774
diff --git a/trunk/fs/attr.c b/trunk/fs/attr.c
index 0da90951d277..29e38a1f7f77 100644
--- a/trunk/fs/attr.c
+++ b/trunk/fs/attr.c
@@ -171,6 +171,8 @@ int notify_change(struct dentry * dentry, struct iattr * attr)
 	struct timespec now;
 	unsigned int ia_valid = attr->ia_valid;
 
+	WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
+
 	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | ATTR_TIMES_SET)) {
 		if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
 			return -EPERM;
@@ -250,5 +252,4 @@ int notify_change(struct dentry * dentry, struct iattr * attr)
 
 	return error;
 }
-
 EXPORT_SYMBOL(notify_change);