[systemd-devel] Second (erroneous) check of rootfs?

[Nikolai Zhubr]

Hi,
11.01.2015 10:09, Andrei Borzenkov:
>> Ok. I've invented a quick-and-dirty fix. I'll modify systemd-fsck so
>> that when run with no argument it does nothing and exit successfully.
>> This way I'll still have rootfs fsck'ed every boot, but never twice.
>>
>
> Uh. Why not simply mount rootfs rw in initrd then?

I'm not against generally. But it'd mean that this first mount is 
actually a real mount, the fs will start up in full. Then I'd suppose it 
is definitely a must to supply all necessary mount options (from fstab) 
at this stage already. I don't easily see how to do this currently, at 
least on my opensuse system.

>> Hope someone will come up with a better solution though :)
>
> The more I think about it the more I find it non-issue. As was already
> mentioned, systemd-fsck checks whether rootfs is mounted read-write and
> will skip check in this case. Could someone give a compelling reason why
> initrd would want to mount rootfs read-only after having fsck'ed it?

That might indeed be a relict of some ancient established techniques of 
system maintenance and repair, which no longer reasonably apply now, but 
I'm no expert in this actually.
>
> Otherwise the only way to prevent second fsck is to pass some flag from
> initrd to real root, like /run/systemd/fsck-root-done.

I like this idea. Quite generic and simple, and allowing a quick fix for 
existing systems while avoiding risky intrusive changes.


Thank you,
Nikolai