Re: [PATCH v4 5/6] btrfs: implement shutdown ioctl

David Sterba
2025-07-08T00:53:45Z

On Tue, Jul 08, 2025 at 08:34:09AM +0930, Qu Wenruo wrote:
> > I have working prototype for pausing scrub that does not need to exit,
> > so far I've tested it with fsfreeze in a VM, I still need to test actual
> > freezing for suspend purposes.
>
> Not sure how would you test with running scrub and freeze, but please
> enable lockdep for the potential reversed lock sequence related to btrfs
> specific locks and s_umount/s_writers.rw_sem.

I used debug_show_held_locks(current) in the task and it showed only the
writers rwsem, once dropped there were no other locks held.

The test is a started scrub with a low bw limit so it takes long enough,
then either from script or manually I do fsfreeze.