Created attachment 162546 [details] It doesn't fill Plasma 6 Wayland from git master with a 4K screen normally run at 200% scale. Ran into this while testing Bug 476002. STEPS TO REPRODUCE 1. Have a 4K screen normally run at 200% scale 2. Right-click on desktop > Configure Display Settings 3. Set resolution to 1080p and scale to 100% OBSERVED RESULT Screen area is reduced to a one-quarter sized rectangle in the top-left corner of the physical screen. See attached screenshot. EXPECTED RESULT Screen area fills the entire physical screen, and content is slightly blurry due to the reduced resolution. ADDITIONAL INFORMATION Rebooting does not resolve the issue.
On my laptop at least, KWin is doing everything correctly; the driver has some bugs with KWin-generated modes, but those are driver bugs. Can you attach your drm_info while in a lower resolution mode, so that we can check if it's also a driver bug in your case?
Created attachment 162601 [details] drm_info
> │ ├───CRTC 0 > │ │ ├───Object ID: 51 > │ │ ├───Legacy info > │ │ │ ├───Mode: 3840x2160@60.00 preferred driver phsync nvsync Interestingly, in your case the display mode is still 4k, so from a driver perspective, the result you're seeing is correct. Now we just need to find out why KWin doesn't set the correct mode... on my laptop it gets set correctly. One possibility could be that the Intel driver doesn't require ALLOW_MODESET to change the mode on your display. If that's the case, then https://invent.kde.org/plasma/kwin/-/merge_requests/4495 should fix this
Yup, that fixes it for me.
Git commit ff2bc0798fe659f6388cf54b6bf3ed0a26785b40 by Xaver Hugl. Committed on 01/11/2023 at 22:29. Pushed by zamundaaa into branch 'master'. backends/drm: fix properties not being applied when a modeset is not needed When testing whether or not a modeset is needed, all that gets tested is whether or not the kernel would allow the commit to happen without the ALLOW_MODESET flag. If there's properties that are only changed in DrmPipeline::prepareAtomicModeset, we need to apply those in the next commit, regardless of whether or not the ALLOW_MODESET flag is necessary. M +33 -19 src/backends/drm/drm_pipeline.cpp M +2 -0 src/backends/drm/drm_pipeline.h https://invent.kde.org/plasma/kwin/-/commit/ff2bc0798fe659f6388cf54b6bf3ed0a26785b40
*** Bug 476470 has been marked as a duplicate of this bug. ***