diff --git a/fs/block_dev.c b/fs/block_dev.c
index ac7031f..b3c1eff 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -285,6 +285,8 @@
 	INIT_LIST_HEAD(&bdev->bd_holder_list);
 #endif
 	inode_init_once(&ei->vfs_inode);
+	/* Initialize mutex for freeze. */
+	mutex_init(&bdev->bd_fsfreeze_mutex);
 }
 
 static inline void __bd_forget(struct inode *inode)