When starting new user session, new gdm session may spawn

[Eugene Romanenko]

Sometimes, when user start new session, gdm session may spawn several times.

Example:
- System started, gdm session at tty1.
- User eugene enter. Eugene session at tty2.
- User vladik start new session from locked screen. Vladik session at tty4, and, unexpected, second gdm session at tty3!
- After some logins/logouts with another users gdm session spawns more.

Attached output of 'ps -fU gdm'.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: gdm3 3.28.3-0ubuntu18.04.3
ProcVersionSignature: Ubuntu 4.15.0-43.46-generic 4.15.18
Uname: Linux 4.15.0-43-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.9-0ubuntu7.5
Architecture: amd64
Date: Mon Dec 24 16:05:34 2018
SourcePackage: gdm3
UpgradeStatus: No upgrade log present (probably fresh install)

[Daniel van Vugt (vanvugt)]

Indeed, it looks like you have multiple login screen sessions.

[Eugene Romanenko (eros2)]

But why? Looks like gdm bug.

[Daniel van Vugt (vanvugt)]

I can only guess. gdm3 will usually run the login screen on VT1 only. The second login screen on VT3 may be either a pure mistake (gdm3 not knowing what is current at the time), or it might be a fallback if changing to VT1 briefly wasn't possible (for some reason). Either way it's failing to clean up.

I suggest the next step is to report the bug to the gdm developers here:

  https://gitlab.gnome.org/GNOME/gdm

And when done please let us know the new bug ID.

[Launchpad Janitor (janitor)]

[Expired for gdm3 (Ubuntu) because there has been no activity for 60 days.]