Comment 31 for bug 1794280

Hi,

I have the same problem since 3 weeks on a fresh install of Ubuntu Cosmic, with Wayland session enabled by default : 2/3 of the time, login screen doesn't appear and screen remains black, pushing power button makes Ubuntu background visible again and computer stops.

I join some Auth.log since 17th September, here is an extract - will do some further tests :

Session c1 logged out. Waiting for processes to exit.
Unregistered Authentication Agent for unix-session:c1 (system bus name :1.35, object path /org/freedesktop/PolicyKit1/AuthenticationAgent, locale fr_FR.UTF-8) (disconnected from bus)
Removed session c1.
session closed for user gdm
session opened for user root by (uid=1000)
Executing command [USER=root] [TTY=unknown] [CWD=/home/valeryan24] [COMMAND=/usr/lib/update-notifier/package-system-locked]
Operator of unix-session:2 successfully authenticated as unix-user:valeryan24 to gain TEMPORARY authorization for action org.debian.apt.install-or-remove-packages for system-bus-name::1.336 [/usr/bin/python3 /usr/bin/update-manager --no-update --no-focus-on-map] (owned by unix-user:valeryan24)
asked to register item /org/freedesktop/secrets/collection/login/1, but it's already registered
[system] Failed to activate service 'org.bluez': timed out (service_start_timeout=25000ms)
Registered Authentication Agent for unix-session:2 (system bus name :1.190 [/usr/bin/gnome-shell], object path /org/freedesktop/PolicyKit1/AuthenticationAgent, locale fr_FR.UTF-8)

New seat seat0.
pam_unix(gdm-launch-environment:session): session opened for user gdm by (uid=0)
New session c1 of user gdm.
session opened for user gdm by (uid=0)
gdm-launch-environment]: pam_unix(gdm-launch-environment:session): session closed for user gdm
Session c1 logged out. Waiting for processes to exit.
Removed session c1.
pam_unix(gdm-launch-environment:session): session opened for user gdm by (uid=0)
New session c2 of user gdm.
pam_systemd(gdm-launch-environment:session): Failed to create session: Start job for unit user-121.slice failed with 'canceled'
session closed for user gdm
session opened for user gdm by (uid=0)
pam_unix(gdm-launch-environment:session): session closed for user gdm
Session c2 logged out. Waiting for processes to exit.
Removed session c2.
systemd: pam_unix(systemd-user:session): session closed for user gdm
systemd-logind[815]: Power key pressed.
systemd-logind[815]: Powering Off...
systemd-logind[815]: System is powering down.