Bug#1126174: gnome-shell[3203]: Page flip failed: drmModeAtomicCommit: Invalid argument

[Simon McVittie]

Control: severity -1 important
Control: tags -1 + trixie moreinfo
Control: forwarded -1 https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/8983

On Thu, 22 Jan 2026 at 20:43:05 -0600, Fierro Viejo wrote:
>Every time I turn on the computer, after authenticating in GDM, the
>signal of the displays is lost and after waiting a few seconds, I press
>Ctrl+Alt+F1 and the authentication screen reappears, in which after
>authenticating again, my previously started session appears.

As you said, this seems to be the same issue as in some other bug 
reports after the Debian 13.3 update, or at least closely related. I've 
opened an upstream issue report for the regression: if you can talk 
directly to upstream rather than having me pass messages between you, 
that might be more efficient!

>The only solution that has worked for me so far was to restart after
>running the following commands:
>
>  sudo cp ~/.config/monitors.xml /var/lib/gdm3/.config/
>  sudo chown Debian-gdm:Debian-gdm /var/lib/gdm3/.config/monitors.xml

This is interesting, because you said that gdm is *working*, but 
altering gdm's monitor layout is working for you as a workaround. That 
suggests that gnome-shell is unable to do the transition from gdm's 
monitor layout to the one you have configured for your own session, but 
if gdm uses a different monitor layout initially, then everything is OK.

Can you still reproduce the bug, for example if you delete 
/var/lib/gdm3/.config/monitors.xml and reboot?

If the bug is still reproducible, can you attach the "good" monitors.xml 
from your own ~/.config/monitors.xml, and the "bad" monitors.xml from 
/var/lib/gdm3/.config/monitors.xml? (Replace serial numbers, etc. with 
**** if you would prefer, as long as it's obvious where you have edited 
it - it's unlikely that the specific serial numbers are relevant!)

     smcv