[arch-projects] [mkinitcpio] [PATCH 2/2] resume: generate a udev rule for specifying device

[Tom Gundersen]

On Tue, Nov 26, 2013 at 11:25 PM, Thomas Bächler <thomas at archlinux.org> wrote:
> Am 26.11.2013 19:00, schrieb Tom Gundersen:
>> On Tue, Nov 26, 2013 at 5:09 PM, Dave Reisner <d at falconindy.com> wrote:
>>> On Tue, Nov 26, 2013 at 04:35:13PM +0100, Thomas Bächler wrote:
>>>> Am 26.11.2013 16:22, schrieb Dave Reisner:
>>>>> I'll ask Harald about this -- Dracut uses a very similar mechanism (but
>>>>> a bit more complex/convoluted).
>>>>
>>>> Nobody said this was easy to solve.
>>>>
>>> Consider the patch shelved for now. It's not something I care about --
>>> just thought I'd take a stab at fixing it for others.
>>
>> Well now I got interested ;-)
>>
>> Could this be solved (in a systemd world) by a systemd generator
>> (running in the initramfs of course) generating a one-shot service
>> which does the RUN from your udev rule, but which is ordered between
>> the <hibernation>.device and local-fs-pre.target?
>
> This should work, but we have to be careful that everything that touches
> file systems is ordered After=local-fs-pre.target.
>
> I would not put this into udev, but use a service file.

Sure, that's what I meant.

> Simply have a
> service ordered Before=local-fs-pre.target, which binds to the
> hibernation device (generated from the resume= option). I have no idea
> what happens if you add another job to systemd in the middle of booting
> up - and doing everything with a service file seems cleaner to me.
>
> FYI, systemd-fsck at .service currently has no ordering to
> local-fs-pre.target, this may lead to races between resuming and fsck.

Ok. Something to keep in mind.

-t