diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index 0b5ecbe..554ac36 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -731,7 +731,8 @@
 	if (IS_ERR(name))
 		return PTR_ERR(name);
 
-	mutex_lock(&mqueue_mnt->mnt_root->d_inode->i_mutex);
+	mutex_lock_nested(&mqueue_mnt->mnt_root->d_inode->i_mutex,
+			I_MUTEX_PARENT);
 	dentry = lookup_one_len(name, mqueue_mnt->mnt_root, strlen(name));
 	if (IS_ERR(dentry)) {
 		err = PTR_ERR(dentry);