Systemd and Custom Early Init Script

[Marko Vojinovic]

On Tue, 05 Feb 2013 19:32:34 +0000
Gordan Bobic <gordan at bobich.net> wrote:

> I'm a not quite up to speed on systemd, so I'm hoping somebody here 
> might point me in the right direction WRT the Fedora systemd init 
> process flow.
> 
> I'm trying to work around bug 529153:
> https://bugzilla.redhat.com/show_bug.cgi?id=529153
> 
> The closest to a workable solution I have come up with is:
> 
> echo -n 0000:00:1c.0:pcie04
> > /sys/bus/pci_express/drivers/pciehp/unbind
> 
> So I need this to run as early as possible during the init sequence,
> as soon as /sys is mounted.
> 
> Before/after which services should this be done?

Systemd does not execute sequentially, but in parallel, so there is no
concept of before and after.

What you want is to write a custom systemd unit file which requires that
local-fs.target has already completed (that makes sure that the
filesystem is already mounted) and then executes your command. Then
systemd will make sure that your script gets executed at the first
possible opportunity after the filesystem mount.

So, you can either learn how to write a custom systemd unit file, or
someone experienced in this should step in to help you. My
understanding of systemd is still only descriptive at best.

HTH, :-)
Marko