Re: [PATCH RFC] btrfs: exit scrub and balance early if the fs is being frozen

[Askar Safin <safinaskar@gmail.com>]

Qu Wenruo <wqu@suse.com>:
> There are some reports that btrfs is unable to be frozen if there is a

I tested your patch on real hardware.

I applied it to current Linux mainline.

I have btrfs-raid on two big disks.

I started "sudo btrfs scrub start -B -d /" and pressed "Suspend" in GUI.

If /sys/power/freeze_filesystems is 0 (this is default), then your patch doesn't work.

If /sys/power/freeze_filesystems is 1, then the system stops to respond for a minute
and then suspends. Here is journalctl:
https://zerobin.net/?e3376d7d056dcb04#LyzGFYeVdWsbZfgC25G4TuSct6QDyZ278gQlZgCfR94= .

As well as I understand from journalctl, systemd tries to freeze userspace
process "btrfs scrub" and fails. Then systemd times out after a minute,
and then suspend proceeds.

So, in short, this is not complete solution yet.

Also I tested Sterba's patch, and it doesn't work either:
https://lore.kernel.org/linux-btrfs/20250720194803.3661-1-safinaskar@zohomail.com/ .

I really want this bug to be fixed. Please, CC me with your future attempts.

-- 
Askar Safin