Comment # 15 on bug 947734 from Dr. Werner Fink

(In reply to Dominique Leuenberger from comment #14)

> The system simply did not perform an update at this moment - and
> systemd-logind 'disappeared from the BUS, tearing X down'

I never ever had seen a disappearing systemd-logind, also the journals do not
show any warning/error from the side of systemd and/or systemd-logind.
Therefore I'd like to see the *complete* journal outout as well as the results
of

     systemctl status --all systemd-logind.service 
     systemctl status --all dbus-org.freedesktop.login1.service
     systemctl status --all dbus.service