Ideas for completing WIP "add unit to switch back to initrd at shutdown" etc

[Ray Strode]

Hi,

On Tue, Jun 12, 2018 at 12:22 PM Alan Jenkins
<alan.christopher.jenkins at gmail.com> wrote:
> I might be abusing your terminology.  And I'm slightly vague about
> "drm-escrow", but I think I've been assuming I can have plymouthd exec()
> into "drm-escrow".  Then there is no child process :-) and there's a
> natural way to detect if exec() of drm-escrow fails e.g. because the
> initrd was rebuilt without plymouth.  I guess I should check my
> assumption by working on this part first.
I hadn't considered that.  If you go that approach, you may need to
audit all the places fd's are created to ensure they're CLOEXEC.

> I think the fdstore wouldn't help with the design.  (I'm familiar with
> it from how logind uses the fdstore for drm devices).
Why not?  Admittedly, I haven't looked into it in detail, beyond the
man page, so you may understand the API better than me.  But
fundamentally, the drm fd just needs to be open, it shouldn't matter
who is holding the fd (be it plymouthd / plymouth-drm-escrow / or
systemd)

--Ray