Bug#791964: gdm3: upgrade causes X session to be terminated

[Josh Triplett]

On Fri, Jul 10, 2015 at 02:37:49PM +0200, Michael Biebl wrote:
> Control: severity -1 serious
> 
> Am 09.07.2015 um 20:14 schrieb David Mohr:
> > Package: gdm3
> > Version: 3.14.2-1
> > Severity: normal
> > 
> > Dear Maintainer,
> > 
> > the changelog reads:
> >   * Systemd has been fixed in v222 to no longer kill services on reload
> >     if BusName is set, so drop that part from 92_systemd_unit.patch.
> > but that is EXACTLY what happened to me right now, in the middle of
> 
> Right. Subsequent reloads of gdm3.service should no longer kill
> gdm3.service though. So this was indeed fixed in v222 but there seems to
> be a specific issue for the upgrade path.
> Once gdm3 has been restarted, a reload no longer causes it to be killed.

Note, though, that it doesn't help for systemd to be upgraded first.
Even if running the new systemd 222, upgrading gdm3 kills the active
session.

> I'm not yet quite sure, if this is a gdm or systemd bug and whether the
> best course of action is to simply re-introduce the workaround patch and
> drop that in stretch+1 or if we drop the reload from gdm3.postinst or if
> this indeed another corner case which is not handled properly in systemd.

For a short-term fix, how about quickly re-introducing the gdm3
workaround?  Then, we can experiment with possible ways to drop it and
(more) carefully test the upgrade paths with packages that haven't been
uploaded yet, and subsequently with experimental.

- Josh Triplett