SUMMARY Sometimes (not clear when exactly), after waking the device up after RAM sleep and/or disk hibernation, the whole screen except for the mouse cursor appears mangled around in a sort of blocky horizontal stripy pattern. This behavior has been observed on Wayland a desktop and a laptop running AMD Radeon HD 7560D and AMD Radeon R6/R7 respectively, with the former being on Arch and the latter on Fedora (and previously Kubuntu). A workaround I found was to switch to another TTY and back again, seems to reset something. STEPS TO REPRODUCE 1. Go into sleep mode 2. Wait some time (just in case, not sure about this step) 3. Wake up device OBSERVED RESULT There is a big chance the lock screen and subsequently the desktop all render distorted, with the mouse cursor rendering fine on top. EXPECTED RESULT Screen renders correctly SOFTWARE/OS VERSIONS Linux: Arch, Kubuntu 25.04, Fedora 42 KDE Plasma Version: 6.3.x KDE Frameworks Version: 6.14.0 Qt Version: 6.9.0
Created attachment 182274 [details] Distorted desktop after blindly logging in Taken with a phone camera, this bug is not visible in screenshots.
This is a driver bug. Switching to a tty and back triggers a modeset, which probably reset some driver state and 'fixes' the issue. Please report this at https://gitlab.freedesktop.org/drm/amd/-/issues, but perhaps we can apply the same workaround for wakeup after suspend too.
A possibly relevant merge request was started @ https://invent.kde.org/plasma/kwin/-/merge_requests/8380
Git commit 6c9744667a846758d8b2fff8f54cd98aa704f230 by Xaver Hugl. Committed on 07/11/2025 at 16:34. Pushed by zamundaaa into branch 'master'. backends/drm: on legacy modesetting, trigger a modeset after suspend In theory, the driver should handle it, but bugs in legacy modesetting aren't super likely to be fixed anytime soon, and we already have the same workaround for tty switches. M +13 -0 src/backends/drm/drm_backend.cpp https://invent.kde.org/plasma/kwin/-/commit/6c9744667a846758d8b2fff8f54cd98aa704f230
Git commit ef0054d9e4f0f240bcdab9e9b4728c45ff50ad2c by Xaver Hugl. Committed on 07/11/2025 at 17:53. Pushed by zamundaaa into branch 'Plasma/6.5'. backends/drm: on legacy modesetting, trigger a modeset after suspend In theory, the driver should handle it, but bugs in legacy modesetting aren't super likely to be fixed anytime soon, and we already have the same workaround for tty switches. (cherry picked from commit 6c9744667a846758d8b2fff8f54cd98aa704f230) Co-authored-by: Xaver Hugl <xaver.hugl@kde.org> M +13 -0 src/backends/drm/drm_backend.cpp https://invent.kde.org/plasma/kwin/-/commit/ef0054d9e4f0f240bcdab9e9b4728c45ff50ad2c