Re: [syzbot] [kernel] WARNING: locking bug in try_to_wake_up

[Hillf Danton]

On Mon, 30 Sep 2024 16:39:29 -0700
> syzbot has found a reproducer for the following issue on:
> 
> HEAD commit:    9852d85ec9d4 Linux 6.12-rc1
> git tree:       upstream
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=13ad839f980000

#syz test

--- x/fs/btrfs/disk-io.c
+++ y/fs/btrfs/disk-io.c
@@ -4315,9 +4315,6 @@ void __cold close_ctree(struct btrfs_fs_
 	if (BTRFS_FS_ERROR(fs_info))
 		btrfs_error_commit_super(fs_info);
 
-	kthread_stop(fs_info->transaction_kthread);
-	kthread_stop(fs_info->cleaner_kthread);
-
 	ASSERT(list_empty(&fs_info->delayed_iputs));
 	set_bit(BTRFS_FS_CLOSING_DONE, &fs_info->flags);
 
@@ -4349,6 +4346,8 @@ void __cold close_ctree(struct btrfs_fs_
 	 */
 	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
 	btrfs_stop_all_workers(fs_info);
+	kthread_stop(fs_info->transaction_kthread);
+	kthread_stop(fs_info->cleaner_kthread);
 
 	/* We shouldn't have any transaction open at this point */
 	warn_about_uncommitted_trans(fs_info);
--