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Harey

Member

From: Bavaria, Germany

Registered: 2007-03-24

Posts: 374

SDDM starts with black screen on NVIDIA Optimus setup

While updating I lost a working Optimus setup.

sddm starts up with a black screen, journald says:

[root@totalbaf ~]# journalctl -b | grep sddm
Dez 04 15:40:23 totalbaf sddm[387]: Initializing...
Dez 04 15:40:23 totalbaf sddm[387]: Starting...
Dez 04 15:40:23 totalbaf sddm[387]: Adding new display on vt 1 ...
Dez 04 15:40:23 totalbaf sddm[387]: Display server starting...
Dez 04 15:40:23 totalbaf sddm[387]: Running: /usr/bin/X -nolisten tcp -auth /var/run/sddm/{9d72db30-c7c3-45b3-a6a0-c1959248bee3} -background none -noreset -displayfd 17 vt1
Dez 04 15:40:24 totalbaf sddm[387]: Running display setup script  "/usr/share/sddm/scripts/Xsetup"
Dez 04 15:40:24 totalbaf sddm[387]: Display server started.
Dez 04 15:40:24 totalbaf sddm[387]: Socket server starting...
Dez 04 15:40:24 totalbaf sddm[387]: Socket server started.
Dez 04 15:40:24 totalbaf sddm[387]: Greeter starting...
Dez 04 15:40:24 totalbaf sddm[387]: Adding cookie to "/var/run/sddm/{9d72db30-c7c3-45b3-a6a0-c1959248bee3}"
Dez 04 15:40:24 totalbaf sddm-helper[442]: [PAM] Starting...
Dez 04 15:40:24 totalbaf sddm-helper[442]: [PAM] Authenticating...
Dez 04 15:40:24 totalbaf sddm-helper[442]: [PAM] returning.
Dez 04 15:40:24 totalbaf sddm-helper[442]: pam_unix(sddm-greeter:session): session opened for user sddm by (uid=0)
Dez 04 15:40:24 totalbaf systemd[1]: Created slice User Slice of sddm.
Dez 04 15:40:24 totalbaf systemd-logind[376]: New session c1 of user sddm.
Dez 04 15:40:24 totalbaf systemd[1]: Started Session c1 of user sddm.
Dez 04 15:40:24 totalbaf systemd[444]: pam_unix(systemd-user:session): session opened for user sddm by (uid=0)
Dez 04 15:40:24 totalbaf sddm[387]: Greeter session started successfully
Dez 04 15:40:24 totalbaf sddm-greeter[450]: Reading from "/usr/share/xsessions/plasma-mediacenter.desktop"
Dez 04 15:40:24 totalbaf sddm-greeter[450]: Reading from "/usr/share/xsessions/plasma.desktop"
Dez 04 15:40:24 totalbaf sddm-greeter[450]: Connected to the daemon.
Dez 04 15:40:24 totalbaf sddm[387]: Message received from greeter: Connect
Dez 04 15:40:24 totalbaf sddm-greeter[450]: QObject: Cannot create children for a parent that is in a different thread.
Dez 04 15:40:24 totalbaf sddm-greeter[450]: QObject: Cannot create children for a parent that is in a different thread.
Dez 04 15:40:24 totalbaf sddm-greeter[450]: QObject: Cannot create children for a parent that is in a different thread.
Dez 04 15:40:24 totalbaf sddm-greeter[450]: QObject: Cannot create children for a parent that is in a different thread.
Dez 04 15:40:24 totalbaf sddm-greeter[450]: QObject: Cannot create children for a parent that is in a different thread.
Dez 04 15:40:24 totalbaf sddm-greeter[450]: QObject: Cannot create children for a parent that is in a different thread.
Dez 04 15:40:24 totalbaf sddm-greeter[450]: QObject: Cannot create children for a parent that is in a different thread.
Dez 04 15:40:24 totalbaf sddm-greeter[450]: QObject: Cannot create children for a parent that is in a different thread.
Dez 04 15:40:24 totalbaf sddm-greeter[450]: QObject: Cannot create children for a parent that is in a different thread.
Dez 04 15:40:24 totalbaf sddm-greeter[450]: QObject: Cannot create children for a parent that is in a different thread.
Dez 04 15:40:24 totalbaf sddm-greeter[450]: QObject: Cannot create children for a parent that is in a different thread.
Dez 04 15:40:24 totalbaf sddm-greeter[450]: QObject: Cannot create children for a parent that is in a different thread.
Dez 04 15:40:24 totalbaf sddm-greeter[450]: QObject: Cannot create children for a parent that is in a different thread.
Dez 04 15:40:24 totalbaf sddm-greeter[450]: QObject: Cannot create children for a parent that is in a different thread.
Dez 04 15:40:24 totalbaf sddm-greeter[450]: QObject: Cannot create children for a parent that is in a different thread.
Dez 04 15:40:24 totalbaf sddm-greeter[450]: QObject: Cannot create children for a parent that is in a different thread.
Dez 04 15:40:24 totalbaf sddm-greeter[450]: QObject::installEventFilter(): Cannot filter events for objects in a different thread.
Dez 04 15:40:25 totalbaf sddm-greeter[450]: QObject: Cannot create children for a parent that is in a different thread.
Dez 04 15:40:25 totalbaf sddm-greeter[450]: QObject::installEventFilter(): Cannot filter events for objects in a different thread.
Dez 04 15:40:25 totalbaf sddm-greeter[450]: Adding view for ":0.0" QRect(0,0 640x480)
Dez 04 15:40:25 totalbaf sddm-greeter[450]: QXcbConnection: XCB error: 148 (Unknown), sequence: 163, resource id: 0, major code: 140 (Unknown), minor code: 20
Dez 04 15:40:25 totalbaf sddm-greeter[450]: QDBusConnection: name 'org.freedesktop.UDisks2' had owner '' but we thought it was ':1.19'
Dez 04 15:40:25 totalbaf sddm-greeter[450]: Message received from daemon: Capabilities
Dez 04 15:40:25 totalbaf sddm-greeter[450]: Message received from daemon: HostName

During the update I had to change this part in xorg.conf:

Section "ServerLayout"
    Identifier "layout"
    Screen 0 "nvidia"
    Inactive "intel"
EndSection

to

Section "ServerLayout"
    Identifier "layout"
    Screen 1 "nvidia"
    Inactive "intel"
EndSection

defining the screen as '1' instead of '0' as before.

If I disable sddm and start x via 'startx' KDE5 starts up as expected.

I suspect sddm tries to open its objects on the wrong Screen. Is there anyone having a solution for this?

Greetings
Harvey

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Linux is like a wigwam: No Gates, no Windows and an Apache inside

Harey

Member

From: Bavaria, Germany

Registered: 2007-03-24

Posts: 374

Re: SDDM starts with black screen on NVIDIA Optimus setup

Really nobody, not even with a clue? Is it that obvious and I am overlooking something too simple or is it really that difficult to debug? Meanwhile I got a private mail from somebody that has the same problem. At least I am not alone

Harvey

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Linux is like a wigwam: No Gates, no Windows and an Apache inside

mrunion

Member

From: Jonesborough, TN

Registered: 2007-01-26

Posts: 1,938

Website

Re: SDDM starts with black screen on NVIDIA Optimus setup

Are you running into this? https://bugs.archlinux.org/task/47151

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Matt

"It is very difficult to educate the educated."

Harey

Member

From: Bavaria, Germany

Registered: 2007-03-24

Posts: 374

Re: SDDM starts with black screen on NVIDIA Optimus setup

Yep, that seems to be exactly my case. Meanwhile I installed Ubuntu which runs beautifully using the PRIME approach. Will investigate further when my son allows me to touch the laptop again

Thank you
Harvey

---

Linux is like a wigwam: No Gates, no Windows and an Apache inside