FS#64985 - [gdm] [PATCH] GDM fails to start when GPU initialization takes too long

Attached to Project: Community Packages
Opened by Marti (intgr) - Sunday, 29 December 2019, 22:30 GMT
Last edited by freswa (frederik) - Sunday, 11 October 2020, 15:42 GMT
Task Type Bug Report
Category Packages
Status Closed
Assigned To Jan Alexander Steffens (heftig)
Architecture All
Severity High
Priority Normal
Reported Version
Due in Version Undecided
Due Date Undecided
Percent Complete 100%
Votes 2
Private No


For several months I've had issues where GDM fails to start on boot. Finally I got around to debugging this issue, which turns out to be a known upstream bug: https://gitlab.gnome.org/GNOME/gdm/issues/103

Other distros (Ubuntu and Gentoo at least) contain a kludge to solve this: https://gitweb.gentoo.org/repo/gentoo.git/tree/gnome-base/gdm/files/gdm-CanGraphical-wait.patch
(Commit: https://gitweb.gentoo.org/repo/gentoo.git/commit?id=85ea6bed8c994eae9891af1a2fba0e99aa1c3031 )

The mechanism of this workaround is following:

* Workaround for LP: #1794280.
* That bug is because the DRM device isn't ready by the time GDM tries to
* start wayland/X.
* This is a script to add to ExecStartPre of gdm.service. It does the
* following:
* 1. Enumerate drm devices from udev, looking for a DRM master. If found,
* exit.
* 2. Connect to the 'uevent' signal of gudev, watching for the same to be
* added. Again exit if any are found.
* 3. If, after 10 seconds, we haven't seen anything, try to proceed anyway as
* a failsafe.

Additional info:
* package version(s)
gdm 3.34.1-1
* config and/or log files etc.
Failure with GDM: https://gist.github.com/intgr/a7eee474994e8a845405a7466ac2ebc2
Success with LightDM: https://gist.github.com/intgr/dc3e9ae46be8f78b48e0bc0402139608
* link to upstream bug report, if any

Possible workarounds:
* Many users in forums are recommending "early KMS" to fix GDM issues: https://wiki.archlinux.org/index.php/Kernel_mode_setting#Early_KMS_start
This task depends upon

Closed by  freswa (frederik)
Sunday, 11 October 2020, 15:42 GMT
Reason for closing:  Duplicate
Additional comments about closing:   FS#63763 
Comment by Marti (intgr) - Sunday, 29 December 2019, 22:52 GMT
I tested out the patch on my system and it works. Here's diff to the PKGBUILD (using 'asp'): https://gitlab.com/intgr/arch-pkg-gdm/commit/b1f96ef17c1d03a7764d244120fb8f15f95951cd
Comment by Marti (intgr) - Sunday, 29 December 2019, 23:07 GMT
Darn FlySpray, I can never find the right bugs because it's searching in the wrong "project".

Probably duplicate of this: https://bugs.archlinux.org/task/63763