[systemd-devel] [PATCH 3/3] Use a stamp file to avoid running systemd-fsck-root.service twice

[Zbigniew Jędrzejewski-Szmek]

On Tue, May 05, 2015 at 10:48:48AM +0200, Harald Hoyer wrote:
> On 03.05.2015 17:33, Zbigniew Jędrzejewski-Szmek wrote:
> > On Sun, May 03, 2015 at 06:06:58PM +0300, Andrei Borzenkov wrote:
> >> В Sun, 3 May 2015 16:17:15 +0200
> >> Lennart Poettering <lennart at poettering.net> пишет:
> >>
> >>> On Sat, 02.05.15 13:16, Zbigniew Jędrzejewski-Szmek (zbyszek at in.waw.pl) wrote:
> >>>
> >>> So, the last time we discussed this we figured we should do this
> >>> differently, and simply generate systemd-fsck-root.service in the
> >>> initrd as well, that uses a different command line internally. The end
> >>> result would then be that we can do without flag file, and always have
> >>> the guarantee that "systemd-fsck-root.service" is the services that
> >>> fsck'ed the root file system, regardless whether in initrd or not.
> >>>
> >>
> >> systemd-fsck at .service has explicit dependency on
> >> systemd-fsck-root.service so other mounts (/usr, anything else?) will
> >> be serialized after it. Currently they can run in parallel.
> >>
> >> Not I think it is a big problem, but at least to consider.
> > Yeah, that's the main wart. I tried to outline it in the second bullet
> > point below.
> > 
> > I prepared a patch to generate systemd-fsck-root.service in
> > generator_write_fsck_deps() first, but I wasn't happy with the result.
> > If we ignore the dependency issue, it might be judged more elegant,
> > since it just uses unit stat to pass information.
> > 
> >>> Harald, can you comment?
> 
> Zbigniew has a point with the ordering.
> 
> But maybe the whole thing is easier than it appears:
> - the initrd can provide a fake systemd-fsck-root.service, with /bin/true
> - if /sysroot (or any needed fsck) is failing fsck, we don't boot the real
> system anyway

Can you have a system with initramfs, with the root mounted initially ro,
which checks the filesystem after transition to the main system? Or is
something which is not supported?

Zbyszek