SUMMARY When connecting a monitor to a secondary gpu with a wayland session, it results in a black screen with laggy mouse. The mouse changes based on what it would hoover (text, resize handles, ...). journalctl shows a lot of lines like this: `kwin_wayland_drm: failed to import gbm_bo for multi-gpu usage: Function not implemented` SOFTWARE/OS VERSIONS Linux/KDE Plasma: OpenSUSE Tumbleweed with KDE unstable repos (bug not present on system repos 5.26.4) (available in About System) KDE Plasma Version: 5.26.80 KDE Frameworks Version: 5.101.0 Qt Version: 5.15.7 ADDITIONAL INFORMATION Observed on 6800H + 6600M (with mux switch). The bug only occurs while using the integrated gpu as primary or an usb to hdmi adapter is used. X11 works fine.
Forgot to specify: only the external display is black, the display of the laptop keeps working normally.
Please attach the output of "journalctl --user-unit plasma-kwin_wayland --boot 0" and drm_info (https://gitlab.freedesktop.org/emersion/drm_info). If you can build KWin yourself, can you check out commit cd6a21996135d4ac40c0eee1b5d283e1bc844797 and see if the issue was present there already?
(In reply to Zamundaaa from comment #2) > Please attach the output of "journalctl --user-unit plasma-kwin_wayland > --boot 0" and drm_info (https://gitlab.freedesktop.org/emersion/drm_info). > > If you can build KWin yourself, can you check out commit > cd6a21996135d4ac40c0eee1b5d283e1bc844797 and see if the issue was present > there already? cd6a21996135d4ac40c0eee1b5d283e1bc844797 works, next one (b3d0698126ac7bd992d253fc3db344bb3137bf6f) indeed does not.
Created attachment 154315 [details] journalctl log
Created attachment 154316 [details] drm_info
Created attachment 154318 [details] drm info with kwin from repos (black screen) the previous drm_info was taken with the working commit
Created attachment 154338 [details] Logging for multi gpu stuff Can you upload the journalctl output again, once for the working commit, and once for the failing one with the attached patch on top?
Created attachment 154346 [details] journal with working kwin
Created attachment 154347 [details] journal with broken kwin + logging
A possibly relevant merge request was started @ https://invent.kde.org/plasma/kwin/-/merge_requests/3280
Can you test the MR?
(In reply to Zamundaaa from comment #11) > Can you test the MR? Hello, it works fine with the iGPU + dGPU configuration, but sadly I cannot test the USB-to-HDMI dongle until tomorrow evening (for the sake of completeness). Cheers
Git commit 3d9ccaf74269285d6dcd76e34bc9a8e040672886 by Xaver Hugl. Committed on 06/12/2022 at 19:55. Pushed by zamundaaa into branch 'master'. backends/drm: fix modifier check If we force a linear modifier, the modifier list can't match up with the display, which causes the surface to be recreated every frame. M +3 -2 src/backends/drm/drm_egl_layer_surface.cpp M +1 -0 src/backends/drm/drm_egl_layer_surface.h https://invent.kde.org/plasma/kwin/commit/3d9ccaf74269285d6dcd76e34bc9a8e040672886
Tested with the USB-to-HDMI dongle and that's working too.