Comment 6 for bug 1723806

On Fri, Nov 10, 2017 at 07:54:33PM -0000, Mathieu Trudel-Lapierre wrote:
> Whether ubiquity is installable is a different issue than console-setup
> breaking on upgrade though. The ubiquity change is being reverted, but
> we still need to figure out why the console-setup upgrade fails.

> I've attempted to set up a virtual machine with Ubuntu Server, where I
> can approximate the upgrade procedure for both server or desktop (by
> changing whether and which plymouth splash shows). I haven't been able
> to reproduce the issue yet.

> It really looks to me like it's an issue with speaking to plymouth while
> doing updates unattended, but am I wrong on that assumption?

During normal operations, plymouth --ping should return immediately because
plymouthd /should not be running/. plymouthd should only be running at boot
and shutdown, and in neither case should we be in the middle of an upgrade.

So this is absolutely a plymouth bug, or multiple distinct plymouth bugs.
It is impractical to know with 100% confidence when and if we have fixed
these bugs. This is why I agree with Adam's position that we should instead
fix the behavior of plymouth --ping so that it has some sort of timeout
mechanism instead of blocking indefinitely, in order to make maintainer
scripts that need to check plymouth more robust in the face of hanging
plymouthds.