LightDM GTK greeter doesn't switch to greeter VT

[davidak]

Issue description

Setup: Thinkpad X230 with no external display

I'm not able to reactivate the screen to login.

I tried moving finger on touchpad, clicking touchpad, hitting many buttons on keyboard including power button...

You hopefully find hints in the log at around 17:30 to 18:00. Then i pressed the ALT key and screen went on.

syslog_today.txt

@worldofpeace

Steps to reproduce

0. leave computer running and go away for some time
1. session get's locked
2. i'm not able to unlock. the screen remains dark but i can ping the system, so it seems running

Technical details

• system: "x86_64-linux"
• host os: Linux 4.19.36, NixOS, 19.03.172361.cf3e277dd0b (Koi)
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.2.2
• channels(davidak): ""
• channels(root): "nixos-19.03.172361.cf3e277dd0b, nixos-hardware, nixos-unstable-19.09pre177249.dfd8f84aef1"
• nixpkgs: /nix/var/nix/profiles/per-user/root/channels/nixos

[worldofpeace]

I'm pretty sure this is the-cavalry/light-locker#138 and we noticed it in #60082 (comment)

The most helpful issue I've glanced at was the-cavalry/light-locker#114
and details with using modesetting vs intel driver.

Also reports of slick-greeter somehow being immune to the issue.

[worldofpeace]

I'm available on matrix and freenode for suggestions that maybe you can try

[worldofpeace]

@jtojnar Do you have any idea how I should debug this, or who to take issue with?

In the-cavalry/light-locker#114 it described the issue not being present when not using modesetting driver with intel hardware or using an older kernel.

@davidak and I could reproduce this issue going away when using linuxPackages_4_9 or services.xserver.videoDrivers = [ "intel" ];.

[worldofpeace]

Hopeful bugreport against the i915 component

• https://bugs.freedesktop.org/show_bug.cgi?id=110863

It's speculated that's is a poor interaction related to lightdm-gtk-greeter specifically, so another possible workaround would be to not use it.

Edit: it does appear that only slick-greeter doesn't have this issue...

[stale]

Thank you for your contributions.
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[davidak]

i don't had this problem in a long time, so should be fixed

[worldofpeace]

It actually still is an issue, I think, if you use lightdm gtk greeter and lightlocker.
For Pantheon, we don't use lightdm gtk greeter anymore so we never hit that issue.
And as of gala master, it has its own embed screenlocker in the compositor.

[stale]

I marked this as stale due to inactivity. → More info