2 files changed, 13 insertions, 0 deletions

diff --git a/fs/inode.c b/fs/inode.c
index bf6adf122c68..f97de0aeb3b6 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -567,6 +567,18 @@ EXPORT_SYMBOL(new_inode);
 
 void unlock_new_inode(struct inode *inode)
 {
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+        struct file_system_type *type = inode->i_sb->s_type;
+        /*
+         * ensure nobody is actually holding i_mutex
+         */
+        mutex_destroy(&inode->i_mutex);
+        mutex_init(&inode->i_mutex);
+        if (inode->i_mode & S_IFDIR)
+                lockdep_set_class(&inode->i_mutex, &type->i_mutex_dir_key);
+        else
+                lockdep_set_class(&inode->i_mutex, &type->i_mutex_key);
+#endif
         /*
          * This is special!  We do not need the spinlock
          * when clearing I_LOCK, because we're guaranteed
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 0cad20e12585..6d760f1ad875 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1308,6 +1308,7 @@ struct file_system_type {
 
         struct lock_class_key i_lock_key;
         struct lock_class_key i_mutex_key;
+        struct lock_class_key i_mutex_dir_key;
         struct lock_class_key i_alloc_sem_key;
 };