Comment # 16 on bug 1188954 from Dean Martin

(In reply to Felix Miata from comment #15)
> Using systemd-networkd instead of wicked or networkmanager makes the (~6s)
> difference between KMS module finishing loading soon enough or not.
> 
> This is from an xdm startup failing using systemd-networkd:
> # journalctl -b -o short-monotonic -u display-manager.service -u
> systemd-modules-load.service -g St
> -- Journal begins at Sat 2021-01-16 18:26:29 EST, ends at Sat 2021-08-14
> 16:50:47 EDT. --
> [    3.849113] asa88 systemd[1]: Stopped Load Kernel Modules.
> [    6.231843] asa88 systemd[1]: Starting X Display Manager...
> [    7.383982] asa88 display-manager[651]: Starting service tdm
> [    7.384359] asa88 systemd[1]: Started X Display Manager.
> 
> This is from an xdm startup succeeding using wicked:
> # journalctl -b -o short-monotonic -u display-manager.service -u
> systemd-modules-load.service -g St
> -- Journal begins at Fri 2021-08-13 23:33:06 EDT, ends at Sat 2021-08-14
> 17:38:24 EDT. --
> [    3.731005] localhost systemd[1]: Stopped Load Kernel Modules.
> [   13.312481] asa88 systemd[1]: Starting X Display Manager...
> [   13.411758] asa88 display-manager[1013]: Starting service xdm
> [   13.412175] asa88 systemd[1]: Started X Display Manager.
> 
> All my systems are configured with static IP, without IPV6 enabled, and
> without resolvconf of any kind enabled.
> 
> It looks like the summary should be:
> 
> 		display-manager.service starts too soon when using systemd-networkd
> or
> 		using systemd-networkd instead of wicked or networkmanager results in
> 		systemd-modules-load.service functionally finishing after
> display-manager.service starts

That is what using early KMS (module added to initrd) may help with, as Stefan
Dirsch already mentioned back in comment #7.