SUMMARY *** I upgraded to kde-plasma/plasma-meta-5.27.4 today and after the upgrade my external monitors connected to my dGPU stopped working. They were working fine on the previous kde-plasma/plasma-meta (5.26.x) release. I'm using a Lenovo ThinkPad P52 with hybrid graphics where the internal iGPU (Intel i915) is connected to the internal monitor and the external ports are connected to the dGPU (nvidia) via thunderbolt (MUXed system). I've tried re-compiling my graphics drivers, but this did not resolve the issue. No other packages besides kde-plasma and the kde-framework packages were updated. *** STEPS TO REPRODUCE 1. Upgrade to kde-plasma/plasma-meta-5.27.4 2. 3. OBSERVED RESULT External monitors connected to dGPU no longer working EXPECTED RESULT Display on my external monitors SOFTWARE/OS VERSIONS Linux/KDE Plasma: 6.1.23-gentoo / 5.27.4 (available in About System) KDE Plasma Version: 5.27.4 KDE Frameworks Version: 5.104.0 Qt Version: 5.15.9 ADDITIONAL INFORMATION
Additional information: Running gentoo-sources-6.1.23 Running nvidia-drivers-530.41.03 (tried 525.xx.xx series too)
Can you define what "stopped working" means in this context 1. Doesn't get power 2. Gets power, but can't be turned on 3. Can be turned on, but displays no image 4. Displays
4. Displays an "image" that's just all black, but you can at least move your cursor onto the screen and it shows up 5. Something else ?
I'm running X11 and xrandr showed both of the providers and all 3 the monitors, but KDE did not see them in the configuration pane. There it only showed 1 monitor (they were blinking in stand-by). The output was: xrandr --listproviders Providers: number : 2 Provider 0: id: 0x47 cap: 0xf, Source Output, Sink Output, Source Offload, Sink Offload crtcs: 3 outputs: 6 associated providers: 1 name:modesetting Provider 1: id: 0x2a1 cap: 0x2, Sink Output crtcs: 4 outputs: 7 associated providers: 1 name:NVIDIA-G0 xrandr --listmonitors Monitors: 3 0: +*DP-1-1.2 1920/518x1200/324+1920+0 DP-1-1.2 1: +eDP-1 1920/344x1080/193+0+60 eDP-1 2: +DP-1-1.3 1920/518x1200/324+3839+0 DP-1-1.3 I've been able to resolve the issue, by resetting my entire KDE configuration, running the commands below (after entering a new session) and rebooting: xrandr --setprovideroutputsource NVIDIA-G0 modesetting xrandr --auto The issue has been resolved for now, but seems like an issue during upgrade, where wiping the KDE configuration resolves the issue.
Sorry this happened. In Plasma 5.27 we implemented a new system for mapping Plasma desktops and panels to screens that is fundamentally more correct by design, and as a result much more robust. We also added code to migrate old settings to this new system. Unfortunately, due to the non-determinism baked into the old system, the migration code works better the simpler your arrangement of screens, desktops, and panels was. For complex arrangements, we've seen a few reports like this. The good news is that this shouldn't recur going forward due to the new system we have in Plasma 5.27. So hopefully this is the last time it should ever happen!