Arch Linux

Istya_Telperion

Member

Registered: 2016-08-03

Posts: 5

SDDM showing black screen and Plasma - 5.9.3 not initializing

Hi all,

I'm having a difficult time and I have been trying to search for answers and have been unsuccessful so far. I'm running  Plasma 5 with SDDM for my display manager. Here's the problem.

I updated my workstation last evening (I do so about every week) and installed the new updates, including the most recent Plasma update. Upon restarting my workstation I was greeted with a blank screen when I should be presented with SDDM. I can login to other terminals (ALT-SHIFT F2) for example.  I have tried installing another display manager,  lightdm, and I'm able to login through that but then I get greeted with another blank screen but have my cursor which I can move around.

I've looked at /var/log/sddm.log and found that it keeps saying that

QProcess: Destroyed while process ("/usr/lib/sddm/sddm-helper") is still running

It basically starts the display server, starts the greeter, adds a cookie, and then destroys the process.

If anybody could help that would be very very very appreciative as I have no idea what happened but my workstation is unusable right now because of it.

TopKek

Member

Registered: 2017-03-03

Posts: 1

Re: SDDM showing black screen and Plasma - 5.9.3 not initializing

Do you have NVidia/Optimus graphics by any chance? What you describe looks quite like the issue I had recently

If so, you need to edit /usr/share/sddm/scripts/Xsetup and add:
xrandr --setprovideroutputsource modesetting NVIDIA-0
xrandr --auto

so it initializes properly, and these commands need to be done by the respective login manager. Maybe this file got overwritten on update.

Istya_Telperion

Member

Registered: 2016-08-03

Posts: 5

Re: SDDM showing black screen and Plasma - 5.9.3 not initializing

I have tried adding these commands to my Xsetup file (as I have a NVIDIA GTX 980Ti) but unfortunately I'm getting the same black screen at boot.

Istya_Telperion

Member

Registered: 2016-08-03

Posts: 5

Re: SDDM showing black screen and Plasma - 5.9.3 not initializing

Update: I have done a work around in which I bypass SDDM and launch xinit instead but when it does this and tries to bring up Plasma I get a blank screen with a cursor, which I am able to move around. Other than that Plasma won't launch and nothing else will work.

OlafLostViking

Member

From: Lost

Registered: 2013-01-30

Posts: 59

Re: SDDM showing black screen and Plasma - 5.9.3 not initializing

I have the same problem in one of my VMs using QXL. My regular computer (using nvidia) works.

Edit: Sorry, I just realized your error message. My sddm is crashing with a segfault within QQmlThread. So it's probably sth. different.

Last edited by OlafLostViking (2017-03-07 17:43:03)

andrej.podzimek

Member

From: Zürich, Switzerland

Registered: 2005-04-10

Posts: 115

Re: SDDM showing black screen and Plasma - 5.9.3 not initializing

I have (most likely) a similar issue: https://bugs.archlinux.org/task/53374

Last edited by andrej.podzimek (2017-03-19 21:54:20)