LightDM not starting, leads to blank screen with No Signal on monitor

[frosty island]

Anytime I attempt to boot my PC, I am lead to a blank black screen when lightDM should load. My monitor will also report no signal after a couple of seconds.

I have experienced this issue for a couple days now, and it has been occuring with ANY kernel I use, whether it be the built in 6.8 kernel, the 6.11 HWE kernel, or even unofficial kernels such as Xanmod. As of typing this up I am booted in with the 6.11 HWE kernel

I am able to get to a desktop by pressing control+alt+F4 to get to a TTY, logging in, and then executing startx, however this is not an ideal solution.

I also tried removing quiet splash from grub but this didnt help at all and I didnt manage to see anything during boot that might indicate anything awry

If it helps, my GPU is a XFX RX 7700 XT 12GB. Please let me know what logs or anything I can pull to help

[frosty island]

Of note too I can enable automatic login and my desktop will load, but I would rather not use this

[frosty island]

Quick update! I found the culprit

I may have found the culprit causing my no signal issue with lightdm with my AMD gpu. It appears that the latest available libpciaccess ( 0.17.3-ubuntu0.24.04.1) is what is causing this.

I also found a thread on the mint forums about this too, and in a reddit thread as well! https://forums.linuxmint.com/viewtopic.php?t=448655.

https://www.reddit.com/r/linuxmint/comments/1ln0p6y/libpciaccess_causes_black_screen_on_startup/)

It also appears this impacts Ubuntu Plucky
https://bugs.launchpad.net/ubuntu/+source/libpciaccess/+bug/2115574

I am currently holding/blacklisting this update until this is sorted

[naive tundra]

Unforuntately I did not have a timeshift backup. But was able to revert the libpciaccess package by doing the following:

1. Check if the old version is still on your system:
   apt-cache madison libpciaccess0

It was in my case:
libpciaccess0 | 0.17-3build1 | http://archive.ubuntu.com/ubuntu noble/main amd64 Packages < Non-faulty version:

2. Downgrade it:
   sudo apt install libpciaccess0=0.17-3build1

3. Prevent it from being auto-updated:
   sudo apt-mark hold libpciaccess0

[frosty island]

Nice! This is an even easier way

[naive tundra]

Curious to know, how did you figure out it was libpciaccess causing this? 😄

[frosty island]

I installed the updates one by one and the second I installed that one it broke