Re: trixie: can't log in from lightdm.

[David <bouncingcats@gmail.com>]

On Tue, 16 Sept 2025 at 22:44, Charles Curley
<charlescurley@charlescurley.com> wrote:

> I rebooted, and tried to log in. I got a very brief message, then was
> thrown back to lightdm.
>
> I can go to a console and log in to my user account. I can then run
> startx, and I am back in my usual session.
>
> I had made some changes to lightdm-gtk-greeter.conf, but have backed
> those out entirely. Similar changes work fine on other systems, and I
> got the same failure to log in when I had those changes made.
>
> I have preserved a log of the effort to log in from lightdm.
> Unfortunately the entire log is too large for paste.debian.net to
> accept, so I truncated the log from when lightdm first launches until
> the end of the long.
>
> https://paste.debian.net/hidden/47b9f916/
>
> That will expire in 90 days.

Hi,

Here's a few stabs in the dark ...
(I'm on Bookworm, not sure if they are relevant to Trixie).

Is the greeter actually running, do you see it?
So that we know that its not a graphics problem?

Did you check for /var/log/lightdm files?

Does
  sudo journalctl -u session-c1.scope -b
give any extra info?

Line 392 of your paste maybe related to this, not sure if important:
  https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1087449

Also your sentence is confusing:
> Similar changes work fine on other systems, and I
> got the same failure to log in when I had those changes made.
It seems to contradict itself, I do not understand how
"work fine" and "got the same failure" would both be true.

What about the other /etc/lightdm/*.conf files?
What happens if you restore the defaults for all of them?

I searched for
  "Failed write utmpx"
or
  "systemd session scope: Killing process"
from your paste, trying that might find clues.