diff --git a/fs/hmdfs/hmdfs.h b/fs/hmdfs/hmdfs.h
index c9940693f3e73e871443e27021bc101829e1dcfc..22d64c162b1076c7f35b5e36cb3907bbdf224762 100644
--- a/fs/hmdfs/hmdfs.h
+++ b/fs/hmdfs/hmdfs.h
@@ -43,7 +43,7 @@
 
 // 20 digits +'\0', Converted from a u64 integer
 #define HMDFS_ACCOUNT_HASH_MAX_LEN 21
-#define CTRL_PATH_MAX_LEN	   21
+#define CTRL_PATH_MAX_LEN	   11
 
 #define HMDFS_SUPER_MAGIC 0x20200302
 
diff --git a/fs/hmdfs/main.c b/fs/hmdfs/main.c
index 10d37cbac2efaae86291fc00a8021ac61e876afd..db4f58d453911317072659b118493a70d91454e2 100644
--- a/fs/hmdfs/main.c
+++ b/fs/hmdfs/main.c
@@ -864,7 +864,6 @@ static int hmdfs_fill_super(struct super_block *sb, void *data, int silent)
 	struct super_block *lower_sb;
 	struct dentry *root_dentry;
 	char ctrl_path[CTRL_PATH_MAX_LEN];
-	uint64_t ctrl_hash;
 
 	if (!raw_data)
 		return -EINVAL;
@@ -901,9 +900,8 @@ static int hmdfs_fill_super(struct super_block *sb, void *data, int silent)
 		goto out_freesbi;
 
 	// add ctrl sysfs node
-	ctrl_hash = path_hash(sbi->local_dst, strlen(sbi->local_dst), true);
-	scnprintf(ctrl_path, CTRL_PATH_MAX_LEN, "%llu", ctrl_hash);
-	hmdfs_debug("hash %llu", ctrl_hash);
+	scnprintf(ctrl_path, CTRL_PATH_MAX_LEN, "%u", sb->s_dev);
+	hmdfs_debug("s_dev %u", sb->s_dev);
 	err = hmdfs_register_sysfs(ctrl_path, sbi);
 	if (err)
 		goto out_freesbi;