@Richard: I tried your suggestion without luck. The screen remains black, the backlight was switched on. To verify I tried multiple times.
The only true workaround (with KDE) is to switch the compositor off before turning into sleep. You have to switch the compositor on after return from suspend. Somewhere I've found a systemctl script to manage this automatically, but I experienced the script's working not reliable. With KDE you have to press Shift-Alt-F12 to toggle manually the compositor's state. This is the output after returning from suspend with compositor switched off: klaus@Lin:~$ sudo systemctl status plasma-restart@$USER.service ● plasma-restart@klaus.service - Plasma Restart Service Loaded: loaded (/etc/systemd/system/plasma-restart@.service; indirect; vendor preset: enabled) Active: inactive (dead) Mai 03 16:20:59 Lin systemd[1]: plasma-restart@klaus.service: Unit not needed anymore. Stopping. Mai 03 16:20:59 Lin systemd[1]: plasma-restart@klaus.service: Failed to enqueue stop job, ignoring: Transaction is destructive. Mai 03 16:20:59 Lin systemd[1]: Starting Plasma Restart Service... Mai 03 16:20:59 Lin sudo[3652]: klaus : TTY=unknown ; PWD=/home/klaus ; USER=klaus ; COMMAND=/bin/bash -c pkill -ABRT plasmashell Mai 03 16:20:59 Lin sudo[3652]: pam_unix(sudo:session): session opened for user klaus by (uid=0) Mai 03 16:20:59 Lin sudo[3652]: pam_unix(sudo:session): session closed for user klaus Mai 03 16:20:59 Lin systemd[1]: Started Plasma Restart Service. Mai 03 16:20:59 Lin systemd[1]: plasma-restart@klaus.service: Unit not needed anymore. Stopping. Mai 03 16:20:59 Lin systemd[1]: Stopped Plasma Restart Service. Something seems to be wrong, but I'm not the specialist for systemctl scripts. Regards, Klaus -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xserver-xorg-video-amdgpu in Ubuntu. https://bugs.launchpad.net/bugs/1849084 Title: Freeze on system-resume caused by kwin and amdgpu driver To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/kwin/+bug/1849084/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp
