You are not logged in.

#1 2023-05-25 03:12:05

mikpom
Member
Registered: 2020-01-06
Posts: 11

GDM fails to show logins [Solved]

Greetings, Arch-community folks!

I haven't even noticed this disturbing problem until I wanted to try out Wayland by switching it on at the login screen. When I tried that, I saw a blank screen (not black though, but gdm background-colored) without any logins.

I never noticed this because the system auto-logins and I've been bypassing the login screen for ages. Because of that I have no idea when the problem emerged.

Everything is up-to-date on the moment of writing this:

extra/gdm 44.1-1 (gnome) [installed]
    Display manager and login screen
extra/libgdm 44.1-1 [installed]
    Display manager and login screen - support library

Seems like nothing is really happening in journalctl while I that screen. Here I tried to cut the relevant portion: https://pastebin.com/R5khT5SV

Any ideas ?

Thanks,
Mikhail

Last edited by mikpom (2023-05-28 06:05:53)

Offline

#2 2023-05-25 06:47:56

seth
Member
Registered: 2012-09-03
Posts: 48,486

Re: GDM fails to show logins [Solved]

Please use [code][/code] tags, not markdown. Edit your post in this regard.

I tried to cut the relevant portion

"while at that screen" is most likely too late, please post your complete system journal for the boot:

sudo journalctl -b | curl -F 'f:1=<-' ix.io

Offline

#3 2023-05-26 02:13:14

mikpom
Member
Registered: 2020-01-06
Posts: 11

Re: GDM fails to show logins [Solved]

Thanks for looking into that!

Here's the journal : http://ix.io/4wIL

At the end of boot I clicked  on log-out, looked at the blank screen, switched to tty Ctrl-Alt-F2 and issued a reboot. That should be the end of the journal paste.

Last edited by mikpom (2023-05-26 02:16:59)

Offline

#4 2023-05-26 07:50:19

seth
Member
Registered: 2012-09-03
Posts: 48,486

Re: GDM fails to show logins [Solved]

What stick out is that you're running gnome on X11 but GDM is a wayland session, does https://wiki.archlinux.org/title/GDM#Use_Xorg_backend "help"?

Offline

#5 2023-05-27 05:18:20

mikpom
Member
Registered: 2020-01-06
Posts: 11

Re: GDM fails to show logins [Solved]

No, doesn't work.

Here is the journal dump after I uncommented the line

#WaylandEnable=false

http://ix.io/4wNL .

Not sure if this is relevant but I have two graphic cards, one of them designated for GPU pass-through via VFIO.

Offline

#6 2023-05-27 06:15:09

seth
Member
Registered: 2012-09-03
Posts: 48,486

Re: GDM fails to show logins [Solved]

I saw that, but since the actual session works I don't really see this being a kernel-level issue.

gnome-shell crashes when you temrinate the session and goes on to disable all extensions.
Except maybe if this is a monitor configuration thing (though there're no errors)

Broadsword:
Boot the multi-user.target (2nd link below) remove /var/lib/gdm/.config and start the graphical.target (what should get you GDM and hopefully w/ a nice UI)

Offline

#7 2023-05-27 09:50:21

mikpom
Member
Registered: 2020-01-06
Posts: 11

Re: GDM fails to show logins [Solved]

So I have gone through the suggested cycle what (if I got it right) generates completely new /var/lib/gdm/.config . Unfortunately logging out results in the same blank screen sad

Here is an example journal http://ix.io/4wOs

It's not a blocker, I easily get into fully function OS by autologin,  still disturbing though

Thanks,
-Mikhail

Offline

#8 2023-05-27 15:21:57

seth
Member
Registered: 2012-09-03
Posts: 48,486

Re: GDM fails to show logins [Solved]

May 27 16:42:35 mik-PC gdm-password][2267]: pam_unix(gdm-password:auth): authentication failure; logname= uid=0 euid=0 tty=/dev/tty1 ruser= rhost=  user=mikpom
…
May 27 16:42:36 mik-PC systemd[1]: Started Getty on tty2.
May 27 16:42:39 mik-PC login[2272]: pam_faillock(login:auth): User unknown
May 27 16:42:39 mik-PC dbus-daemon[499]: [system] Activating via systemd: service name='org.freedesktop.home1' unit='dbus-org.freedesktop.home1.service' requested by ':1.94' (uid=0 pid=2272 comm="/bin/login -p --       ")
…
May 27 16:42:41 mik-PC login[2272]: pam_unix(login:auth): check pass; user unknown
May 27 16:42:41 mik-PC login[2272]: pam_unix(login:auth): authentication failure; logname= uid=0 euid=0 tty=/dev/tty2 ruser= rhost=
May 27 16:42:41 mik-PC login[2272]: pam_faillock(login:auth): User unknown
May 27 16:42:43 mik-PC login[2272]: FAILED LOGIN 1 FROM tty2 FOR reboot, Authentication failure
May 27 16:42:45 mik-PC login[2272]: pam_unix(login:session): session opened for user root(uid=0) by root(uid=0)

This looks weird - and related to some other thread where fprintd got in the way (but there's no trace of that)

pacman -Qikk pambase gdm

Also disable the autologin, reboot, header over to a different VT and post the journal for maybe a cleaner look at the situation.

Offline

#9 2023-05-28 02:58:18

mikpom
Member
Registered: 2020-01-06
Posts: 11

Re: GDM fails to show logins [Solved]

Ok this is anecdotal situation, mystery solved!

Those weird "authentication failures" turned out as keyboard hits of frustration when looking at that malign login screen. It hints that login kinda works but is hidden "somewhere". I have two graphic cards and two monitors, one of them being plugged into both cards while NOT working in the host (I use it for VMs only). GDM tries to show login on the monitor which doesn't work, while on the "true" monitor I see the background only.

Thanks,
-Mikhail

PS. That second VM-dedicated monitor doesn't work in the host, and I don't know why. It works when VM loads and it takes signal from VFIO-captured card. I have weird glitches when I got to Gnome's Settings->Displays and can't make it work there. This all however is definitely a separate issue I should work on...

Offline

#10 2023-05-28 05:34:22

seth
Member
Registered: 2012-09-03
Posts: 48,486

Re: GDM fails to show logins [Solved]

I had kinda expected that to get solved with the config file erasure, but well…
Please always remember to mark resolved threads by editing your initial posts subject - so others will know that there's no task left, but maybe a solution to find.
Thanks.

Offline

Board footer

Powered by FluxBB