diff --git a/fs/sysv/super.c b/fs/sysv/super.c
index d0c6a007ce83..eda10959714f 100644
--- a/fs/sysv/super.c
+++ b/fs/sysv/super.c
@@ -487,6 +487,7 @@ static int v7_fill_super(struct super_block *sb, void *data, int silent)
 	sbi->s_sb = sb;
 	sbi->s_block_base = 0;
 	sbi->s_type = FSTYPE_V7;
+	mutex_init(&sbi->s_lock);
 	sb->s_fs_info = sbi;
 	
 	sb_set_blocksize(sb, 512);