KDM Causes Black Screen

During bootup, when ‘kdm’ is selected as the default manager in /etc/sysconfig/displaymanger, I am left with a black screen – no kde desktop.

If I then type" Ctrl-Alt-f1" I can get a console prompt. I then login, and can run ‘sudo startx’, and I get to a kde desktop as root, not exactly what I want.

(As an aside, How can I run startx as my non-root user without getting permissions errors, etc?)

If change /etc/sysconfig/displaymanger to use “xdm” or “gdm” for example as the default, I get an xwindows screen with a login box. Not very useful, but at least it shows different behavior.

Any ideas on what I can do to recover from this?

I already have remove .kde4 from my home directory.

I am running 13.1 in Vbox 4.3.8. I don’t think this is a Vbox issue. I have tried moving this ‘clone’ in on other physical machines with the same results.

Thanks for your help – spent a ridiculous amount of time on this already.

Update on my third sentence above. From text mode I did “sudo chmod 4711 /usr/sbin/Xorg” (the path may differ). After that, I was/am able to run “startx” as a non-root user, successfully.

Still trying to learn how to fix things so I can boot into KDE again.

For some strange reason there recently has been a number of “startx by user” questions. For some answers, see:

Thanks for the response. Any idea how to diagnose/fix whatever is causing the black screen while at the same time startx from text mode will start kde?

To be honest you probably should not use startx any more it is being phased out. I always used init 5 and that still works if run as root. Will bring up the KDM or if autologin is set start KDE. In fact it may be where the problem is. so try as root init 5 see what error messages may be generated. Might give a clue

root>init 5 hangs at a small green chameleon screen.
startx will get KDE going successfully.

I want to fix my system so it boots successfully into KDE.
I don’t want to have to ‘startx’ or ‘init 5’ from text mode.
I am only doing that now in an effort to troubleshoot this situation.

Any ideas? Thanks.

On 03/07/2014 03:06 PM, steve98177 pecked at the keyboard and wrote:
> root>init 5 hangs at a small green chameleon screen.
> startx will get KDE going successfully.
>
> I want to fix my system so it boots successfully into KDE.
> I don’t want to have to ‘startx’ or ‘init 5’ from text mode.
> I am only doing that now in an effort to troubleshoot this situation.
>
> Any ideas? Thanks.
>
>

As root or using sudo:


systemctl enable runlevel5.target

Should get you booting to the KDE login screen after a reboot.

Ken

Ken, what would “target” be? Doesn’t work as stated. Thanks

On 03/08/2014 01:06 PM, steve98177 pecked at the keyboard and wrote:
> Ken, what would “target” be? Doesn’t work as stated. Thanks
>
>

Sorry still getting used to systemd. Should be:



systemctl set-default runlevel5.target


man systemctrl is your friend.

Ken

I’m also having this issue.
It happens every 3 or 4 weeks, usually when I have an important project due.

I’m running openSuse 13.1 64bit natively, not in a virtual machine
I turn my machine on and it just gets to a a black screen with the mouse pointer.
Every thing is normal including the 5 icons fading in on the boot/splash screen, and everything fades out just before the desktop background fades in, but the desktop never fades in, it just stays black.

I can move the mouse around, have no right click menu. I can press the power button and I get the logout/restart/turn off menu.
I can logout, then log in again but I just get the same black screen with the mouse pointer.
I can get to text mode with Ctrl Alt F1.
I shut down my machine every night.

Is there any error log I should check?

Usually I press the power button, login, turn off auto login, restart, turn on auto login and it’s fine for a while, but then I do some updates and it breaks again.

Right now that’s not working and I can’t workout how to get to the desktop.

13.1 is not one of the reliable versions of openSUSE 11.2 or 11.4 was better than this. I’ve been a user since 9.2 and the quality is deteriorating.

I’ve been digging through the logs and found this in /var/log/kdm.log
klauncher(5286) kdemain: No DBUS session-bus found. Check if you have started the DBUS server
kdeinit4: Communication error with launcher. Exiting!

Hm, never seen something like that. Except for the 13.1 Beta versions, where KDE’s task manager had a bug which made plasma-desktop crash on login on 32bit systems.
But this should be fixed since a long time.

If you do have a mouse pointer, it is apparently plasma-desktop crashing.
Do you get a “Run command” window when you press Alt+F2?
If yes, try to run “plasma-desktop” manually. Does this work?

Or run “konsole” and then try to run “plasma-desktop” in the Konsole window. Do you get an error message?

Something like this could be graphics driver related though.

Which graphics card/driver do you have?
Please install the package “Mesa-demo-x” and post the output of:

glxinfo | grep render

(run this as normal user in Konsole)

That’s “normal” and nothing to worry about.
And as I said, I don’t think it’s KDM that’s crashing, but plasma-desktop.
Have you maybe added some plasmoid to the desktop/panel that might cause it to crash on startup?
Error messages should be in ~/.xsession-errors-:0, or run it on Konsole as mentioned.

Does logging in work if you create a new user? (YaST->Security and Users->User and Group Management, you can run YaST in text mode as well, or try Alt+F2)

I’ve found the problem. The network cable slipped out of the network switch. Plugged it in and it starts normally.
I’m not sure why no network should prevent a boot.

glxinfo returns If glxinfo is not a typo … try cnf glxinfo. I will need to install that package.
I have a Nvidia Graphics card “Asus ENGTS250 DK 1G”

I started again without network and Alt + F2 gives a little box at the top of the screen.
Typing plasma-desktop does nothing, but I can start Firefox from the Alt F2 box or get the System Settings box up.
Thanks for the Alt F2 tip. I will be able to use that next time.

I can do some more testing for you if it helps build a better openSUSE, because the problem is reproducable, but I might as well just remember to check the network cable is plugged in.

Thanks for your help,
Steve

Your system boots up fine, but plasma-desktop hangs at startup.
This is most likely caused by some plasmoid that hangs when there’s no network connection.
I am aware of exactly that issue with the “Remember The Milk” plasmoid. Are you using that?
This one just hangs if it cannot reach the server. And it doesn’t even recover when the network connection is established later, which happens if it is a user connection in NetworkManager.

glxinfo returns If glxinfo is not a typo … try cnf glxinfo. I will need to install that package.
I have a Nvidia Graphics card “Asus ENGTS250 DK 1G”

Not necessary any more, because you already found the cause for your issue.

Yes I have Remember the Milk. It’s good to know the cause. Perhaps I should remove it.
Thanks again for your help.

Steve

FYI, there are bug reports about this:
https://bugs.kde.org/show_bug.cgi?id=254275
https://bugs.kde.org/show_bug.cgi?id=322431
https://bugs.kde.org/show_bug.cgi?id=315414

But apparently the maintainer doesn’t care (or has disappeared, or whatever).

I do have in mind trying to fix it myself if I find some time, but I cannot tell when that will be (or whether I succeed… :wink: ).

A workaround would be to run it in a window:

plasma-windowed plasma_applet_rtm

Then it would not hang the whole plasma session, and you could close and restart it when there was no network on startup.
KDE’s session management should automatically restart it on login if it was running on logout.