Re: [PATCH 0/2] Prevent re-use of FUSE superblock after force unmount

From: Miklos Szeredi <miklos@szeredi.hu>
To: Daniil Lunev <dlunev@chromium.org>
Cc: linux-fsdevel@vger.kernel.org,
	fuse-devel <fuse-devel@lists.sourceforge.net>,
	linux-kernel@vger.kernel.org,
	Alexander Viro <viro@zeniv.linux.org.uk>
Subject: Re: [PATCH 0/2] Prevent re-use of FUSE superblock after force unmount
Date: Wed, 11 May 2022 12:34:54 +0200	[thread overview]
Message-ID: <CAJfpegsNwsWJC+x8jL6kDzYhENQQ+aUYAV9wkdpQNT-FNMXyAg@mail.gmail.com> (raw)
In-Reply-To: <CAONX=-cxA-tZOSo33WK9iJU61yeDX8Ct_PwOMD=5WXLYTJ-Mjg@mail.gmail.com>

On Wed, 11 May 2022 at 11:37, Daniil Lunev <dlunev@chromium.org> wrote:
>
> > No progress has been made in the past decade with regard to suspend.
> > I mainly put that down to lack of interest.
> >
> That is unfortunate.
>
> > It is a legitimate operation, but one that is not guaranteed to leave
> > the system in a clean state.
> Sure, I don't think I can argue about it. The current behaviour is a problem,
> however, since there is no other way to ensure the system can suspend
> reliably but force unmount - we try normal unmount first and proceed with
> force if that fails. Do you think that the approach proposed in this patchset
> is a reasonable path to mitigate the issue?

At a glance it's a gross hack.   I can think of more than one way in
which this could be achieved without adding a new field to struct
super_block.

But...  what I'd really prefer is if the underlying issue of fuse vs.
suspend was properly addressed instead of adding band-aids.  And that
takes lots more resources, for sure, and the result is not guaranteed.
But you could at least give it a try.

Thanks,
Miklos