Btrfs: sysfs: fix, btrfs_release_super_kobj() should to clean up the kobject data

The following test case fails indicating that, thread tried to init an initialized object.

kernel: [232104.016513] kobject (ffff880006c1c980): tried to init an initialized object, something is seriously wrong.

btrfs_sysfs_remove_one() self test code:

open_tree()
{
 ::
        ret = btrfs_sysfs_add_one(fs_info);
	if (ret) {
              pr_err("BTRFS: failed to init sysfs interface: %d\n", ret);
                goto fail_block_groups;
        }
+       btrfs_sysfs_remove_one(fs_info);
+       ret = btrfs_sysfs_add_one(fs_info);
+       if (ret) {
+               pr_err("BTRFS: failed to init sysfs interface: %d\n", ret);
+               goto fail_block_groups;
+       }

cleaning up the unregistered kobject fixes this.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>

diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index e8a4c86d274d5c82cda9fc7ac40c6974f429ece8..db2f8aed2b7d1cfe59aafa504a0a488c4e76bbed 100644 (file)
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -439,6 +439,8 @@ static struct attribute *btrfs_attrs[] = {
 static void btrfs_release_super_kobj(struct kobject *kobj)
 {
        struct btrfs_fs_info *fs_info = to_fs_info(kobj);
+
+       memset(&fs_info->super_kobj, 0, sizeof(struct kobject));
        complete(&fs_info->kobj_unregister);
 }