[SOLVED] GDM hangs at startup since today's update (49.1)

cedricmc · 2025-10-12 14:19:14

After last update, systems hangs at startup, specifically at

[OK] Reached target graphical interface

After login through `tty2` and issuing `journalctl -b 0 | grep gdm`, I get:

oct 12 15:49:41 icaro gdm[2008]: Gdm: Failed to listen on userdb socket: Invalid argument

Downgrading `gdm` (49.1-1 -> 49.0.1-1) solves the problem.

$ grep gdm /var/log/pacman.log | tail -n 4
[2025-10-11T19:10:23+0200] [ALPM] upgraded libgdm (49.0.1-1 -> 49.1-1)
[2025-10-11T19:10:24+0200] [ALPM] upgraded gdm (49.0.1-1 -> 49.1-1)
[2025-10-12T16:00:13+0200] [PACMAN] Running 'pacman -U gdm-49.0.1-1-x86_64.pkg.tar.zst'
[2025-10-12T16:00:16+0200] [ALPM] downgraded gdm (49.1-1 -> 49.0.1-1)

UPDATE: The problem is triggered by a dependency on systemd >= 258. See comments below.

Last edited by cedricmc (Today 09:10:59)

seth · 2025-10-12 19:33:02

Does systemdb-userdb otherwise resond?
https://man.archlinux.org/man/core/syst … dbctl.1.en
Race condition? Does it help to delay or restart GDM?

cedricmc · 2025-10-12 23:18:25

`userdbctl` does seem to respond correctly. I don't think it is a race condition, I have disabled `gdm.service` and started it from `tty1`, and yet it hangs.

Here is a complete status output with gdm v49.0.1 (downgraded working system).

$ systemctl status gdm.service
● gdm.service - GNOME Display Manager
     Loaded: loaded (/usr/lib/systemd/system/gdm.service; enabled; preset: disabled)
     Active: active (running) since Mon 2025-10-13 00:45:06 CEST; 4min 15s ago
 Invocation: 65a7a18781964a2a9c6198cdd57e7c90
   Main PID: 2942 (gdm)
      Tasks: 5 (limit: 38073)
     Memory: 6.9M (peak: 27.9M)
        CPU: 165ms
     CGroup: /system.slice/gdm.service
             └─2942 /usr/bin/gdm

oct 13 00:45:05 myhost systemd[1]: Starting GNOME Display Manager...
oct 13 00:45:06 myhost systemd[1]: Started GNOME Display Manager.
oct 13 00:45:11 myhost gdm-password][4544]: gkr-pam: unable to locate daemon control file
oct 13 00:45:11 myhost gdm-password][4544]: gkr-pam: stashed password to try later in open session
oct 13 00:45:11 myhost gdm-password][4544]: pam_unix(gdm-password:session): session opened for user myuser(uid=1000) by myuser(uid=0)
oct 13 00:45:11 myhost gdm-password][4544]: gkr-pam: unlocked login keyring
oct 13 00:45:14 myhost gdm[2942]: Gdm: Child process -2987 was already dead.

Here is a complete status output with gdm v49.1 (upgraded non-working system).

$ systemctl status gdm.service
● gdm.service - GNOME Display Manager
     Loaded: loaded (/usr/lib/systemd/system/gdm.service; enabled; preset: disabled)
     Active: active (running) since Mon 2025-10-13 00:35:31 CEST; 1min 40s ago
 Invocation: d6aef58c55114e97b8cb748559f27cf4
   Main PID: 2487 (gdm)
      Tasks: 4 (limit: 38073)
     Memory: 4M (peak: 7.8M)
        CPU: 23ms
     CGroup: /system.slice/gdm.service
             └─2487 /usr/bin/gdm

oct 13 00:35:31 myhost systemd[1]: Starting GNOME Display Manager...
oct 13 00:35:31 myhost systemd[1]: Started GNOME Display Manager.
oct 13 00:35:31 myhost gdm[2487]: Gdm: Failed to listen on userdb socket: Invalid argument
oct 13 00:35:31 myhost gdm-launch-environment][2508]: pam_succeed_if(gdm-launch-environment:auth): requirement "user ingroup gdm:gnome-initial-setup" not met by user "gdm-greeter"

Last edited by cedricmc (2025-10-12 23:19:02)

seth · 2025-10-13 09:23:20

https://gitlab.gnome.org/GNOME/gdm/-/issues/

Did you change anything about the gdm* user(s) eg. adding a static one to /etc/{shadow,passwd} (to bypass the nsswitch.conf related problem)?

cedricmc · 2025-10-13 09:41:20

No, I had not such problem. I touch few files from /etc, and /etc/nsswitch.conf is not one of which (nor are /etc/{shadow,passwd}).

I've seen upstream that they had a couple of commits related to userdb since 49.0.1...

seth · 2025-10-13 14:33:36

Probably https://gitlab.gnome.org/GNOME/gdm/-/co … bd9315eca8 ?

session opened for user myuser(uid=1000) by myuser(uid=0)

Do you have the same user doubling as UID0 (root)??

cedricmc · 2025-10-13 15:18:51

I believe it is the normal behavior: the user opens the session through su/sudo or an s-bit.

$ journalctl -b 0 | grep pam_unix | grep gdm
oct 13 06:37:42 myhost (systemd)[2225]: pam_unix(systemd-user:session): session opened for user gdm-greeter(uid=60578) by gdm-greeter(uid=0)
oct 13 06:37:51 myhost gdm-password][4137]: pam_unix(gdm-password:session): session opened for user myuser(uid=1000) by myuser(uid=0)
oct 13 06:38:04 myhost (sd-pam)[2229]: pam_unix(systemd-user:session): session closed for user gdm-greeter

According to this, it might be related to this (system suspends twice).

seth · 2025-10-13 18:55:22

So the gist is that gnome 49.1 hard-depends on systemd 258 (and I take you downgraded that because gnome 49 is also broken w/ systemd 258?)?

cedricmc · 2025-10-13 19:10:41

Yes, although what is broken and what depends on whats is not fully clear.

cedricmc · Today 09:09:07

I've updated gdm to 49.1 and systemd to 258.1, and the problem with gdm is gone, however the multiple suspend is back. I'll have to downgrade everything again, sic. I mark this as solved. Thx for the help.

Arch Linux

#1 2025-10-12 14:19:14

[SOLVED] GDM hangs at startup since today's update (49.1)

#2 2025-10-12 19:33:02

Re: [SOLVED] GDM hangs at startup since today's update (49.1)

#3 2025-10-12 23:18:25

Re: [SOLVED] GDM hangs at startup since today's update (49.1)

#4 2025-10-13 09:23:20

Re: [SOLVED] GDM hangs at startup since today's update (49.1)

#5 2025-10-13 09:41:20

Re: [SOLVED] GDM hangs at startup since today's update (49.1)

#6 2025-10-13 14:33:36

Re: [SOLVED] GDM hangs at startup since today's update (49.1)

#7 2025-10-13 15:18:51

Re: [SOLVED] GDM hangs at startup since today's update (49.1)

#8 2025-10-13 18:55:22

Re: [SOLVED] GDM hangs at startup since today's update (49.1)

#9 2025-10-13 19:10:41

Re: [SOLVED] GDM hangs at startup since today's update (49.1)

#10 Today 09:09:07

Re: [SOLVED] GDM hangs at startup since today's update (49.1)

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