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

[Harald Hoyer]

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