Issue with restarting - no display

English Install/Boot/Login
1

I have a problem which has only started to happen in the past month or so on my TW KDE system. When restarting the PC following a zypper dup it seems to start OK as far as I can hear but I have no active monitor and cannot get a console screen up using ctrl/alt/f2 I just have a black monitor. However if I hold down the power key to force a power off and boot normally it comes up with the monitor active and all works fine. It appears that it might be something to do with SDDM as the journal shows :-


Oct 01 09:21:26 Tumbleweed.Crowhill sddm[2274]: Auth: sddm-helper exited successfully
Oct 01 09:21:26 Tumbleweed.Crowhill sddm[2274]: Greeter stopped.
Oct 01 09:21:26 Tumbleweed.Crowhill sddm-helper[2556]: pam_unix(sddm:session): session opened for user stuart(uid=1000) by (uid=0)
Oct 01 09:21:26 Tumbleweed.Crowhill sddm-helper[2556]: Starting: "/usr/etc/X11/xdm/Xsession \"/usr/bin/startplasma-x11\""
Oct 01 09:21:26 Tumbleweed.Crowhill sddm-helper[2569]: Adding cookie to "/run/user/1000/xauth_ANtmNA"
Oct 01 09:21:26 Tumbleweed.Crowhill sddm[2274]: Session started
Oct 01 09:21:36 Tumbleweed.Crowhill systemd[2330]: pam_warn(systemd-user:setcred): function=[pam_sm_setcred] flags=0x8004 service=[systemd-user] terminal=<unknown>] user=[sddm] ruser=<unknown>] rhost=<unknown>]
Oct 01 10:01:49 Tumbleweed.Crowhill sddm[2274]: Authentication error: "Process crashed"
Oct 01 10:01:49 Tumbleweed.Crowhill sddm[2274]: Auth: sddm-helper crashed (exit code 15)
Oct 01 10:01:49 Tumbleweed.Crowhill sddm[2274]: Authentication error: "Process crashed"
Oct 01 10:01:49 Tumbleweed.Crowhill sddm[2274]: Auth: sddm-helper exited with 15
Oct 01 10:01:49 Tumbleweed.Crowhill sddm[2274]: Socket server stopping...
Oct 01 10:01:49 Tumbleweed.Crowhill sddm[2274]: Socket server stopped.
Oct 01 10:01:49 Tumbleweed.Crowhill sddm[2274]: Display server stopping...
Oct 01 10:01:50 Tumbleweed.Crowhill sddm[2274]: Display server stopped.
Oct 01 10:01:50 Tumbleweed.Crowhill sddm[2274]: Running display stop script  "/usr/share/sddm/scripts/Xstop"
Oct 01 10:01:50 Tumbleweed.Crowhill sddm[2274]: Removing display ":0" ...
Oct 01 10:01:50 Tumbleweed.Crowhill sddm[2274]: Adding new display on vt 7 ...
Oct 01 10:01:50 Tumbleweed.Crowhill sddm[2274]: Loading theme configuration from ""
Oct 01 10:01:50 Tumbleweed.Crowhill sddm[2274]: Display server starting...
Oct 01 10:01:50 Tumbleweed.Crowhill sddm[2274]: Running: /usr/bin/X -nolisten tcp -auth /run/sddm/{bf90e37e-1394-4406-82c8-6765290bb3e2} -background none -noreset -displayfd 18 -seat seat0 vt7
Oct 01 10:01:50 Tumbleweed.Crowhill sddm[2274]: Setting default cursor
Oct 01 10:01:50 Tumbleweed.Crowhill sddm[2274]: Running display setup script  "/usr/etc/X11/xdm/Xsetup"
Oct 01 10:01:50 Tumbleweed.Crowhill sddm[2274]: Display server started.
Oct 01 10:01:50 Tumbleweed.Crowhill sddm[2274]: Socket server starting...
Oct 01 10:01:50 Tumbleweed.Crowhill sddm[2274]: Socket server started.
Oct 01 10:01:50 Tumbleweed.Crowhill sddm[2274]: Loading theme configuration from "/usr/share/sddm/themes/Sky-Blue/theme.conf"
Oct 01 10:01:50 Tumbleweed.Crowhill sddm[2274]: Greeter starting...
Oct 01 10:01:50 Tumbleweed.Crowhill sddm[2274]: Signal received: SIGTERM
Oct 01 10:01:50 Tumbleweed.Crowhill sddm[2274]: Socket server stopping...
Oct 01 10:01:50 Tumbleweed.Crowhill sddm[2274]: Socket server stopped.
Oct 01 10:01:50 Tumbleweed.Crowhill sddm[2274]: Display server stopping...

which covers the period from the restart after zypper dup to the point where I forced a power down and reboot normally.

Anyone any ideas please?

Stuart

2

I would try waiting a while before trying Ctrl-Alt-Fn, at least 90 seconds, maybe a few minutes. If it doesn’t help, try unplugging and replugging the keyboard and trying again Ctrl-Alt-Fn.

Do you have another PC to use to try to login remotely? If you can, you could try systemctl restart xdm to see if sddm starts without crashing.

3

What is your graphic card?

4

AMD Ryzen 5 3400G AM4 Processor with Radeon RX Vega 11 Graphics

Stuart

5

Looking at when this happens it would seem to be when SDDM itself is updated during a zypper dup. I just did a zypper dup today and reboot went fine but no SDDM updates.

Stuart

6

OK so I have done several updates recently which resulted in no problems rebooting. However this morning I did a zypper dup and the reboot gave me a black screen with no output being reported by my monitor. Tried to get a console but no luck. Tried ctrl/alt/del and it rebooted but still no screen. It seems that when this happens it requires a complete cold power up before I can get anything on the monitor. Zypper reported that sddm and sddm helper had been deleted but no actual sddm packages appear to have been installed.

So this does seem to be sddm related and in these cases the only safe way to get the PC back is to power off and do a cold boot.

Stuart

7

Might be worth trying, ( and a better option than a power cycle ) the “Magic SysReq”

Press and hold Alt+SysReq (if not marked as such the SysReq key is Print Screen) whilst keying the following sequence: R E I S U B pause a few seconds between each keystroke.

So this does seem to be sddm related and in these cases the only safe way to get the PC back is to power off and do a cold boot.

That sounds almost identical to a problem I had on two AMD based TW systems a while ago, although in my case it was more random in nature and the SysReq sequence was enough to recover. I was unable to establish the cause and finally did away with sddm, now using lightdm, which, incidentally I found I much preferred anyway…

8

I’ve just installed lightdm but can only set it manually and SDDM continues to show in System Settings. I have not seen a way to change the priority for any of the alternatives. It works OK in manual mode. Is there a wiki somewhere for it showing how to configure lightdm?

Stuart

9

Lightdm doesn’t appear to have it’s own wiki per se, but:

https://github.com/canonical/lightdm
https://wiki.archlinux.org/title/LightDM

are two useful sources of information.

The configuration is controlled by “/etc/lightdm/lightdm-gtk-greeter.conf”

These are the available options: https://paste.opensuse.org/view/raw/3e97bd6a

I don’t use auto mode, so can’t comment on that.

10

Sorry, my bad. That should have been: “/etc/lightdm/lightdm.conf”

The configuration for the greeter is controlled by: “/etc/lightdm/lightdm-gtk-greeter.conf”

Options for that are: https://paste.opensuse.org/view/raw/50be2d8b

11

Thanks I’ll look those up and have a play.

Stuart