Bug 483020

Summary: Artifacts when starting KDE (Wayland) after entering the password in SDDM
Product: [Plasma] kwin Reporter: Maxim <mxtyulkin>
Component: wayland-genericAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED UPSTREAM    
Severity: normal CC: nate, xaver.hugl
Priority: NOR Keywords: qt6
Version First Reported In: 6.0.1   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description Maxim 2024-03-09 19:20:47 UTC 
STEPS TO REPRODUCE
1. Load system
2. Enter password in SDDM

OBSERVED RESULT
Artifacts in the form of white squares appear for a second.

EXPECTED RESULT
Normal loading to desktop, without artifacts

SOFTWARE/OS VERSIONS
Linux: Arch Linux (Linux LTS 6.6.21-1)
KDE Plasma Version: KDE Plasma 6.0.1
KDE Frameworks Version: 6.0.0
Qt Version: 6.6.2

ADDITIONAL INFORMATION
мар 09 18:34:59 archlinux sddm-helper[574]: Starting Wayland user session: "/usr/share/sddm/scripts/wayland-session" "/usr/lib/plasma-dbus-run-session-if-needed /usr/bin/startplasma-wayland"
мар 09 18:35:04 archlinux kwin_wayland[657]: No backend specified, automatically choosing drm
мар 09 18:35:04 archlinux kwin_wayland[657]: kwin_wayland_drm: drmSetClientCap for Atomic Mode Setting failed. Using legacy mode on GPU "/dev/dri/card1"
мар 09 18:35:05 archlinux kwin_wayland[657]: OpenGL vendor string:                   AMD
мар 09 18:35:05 archlinux kwin_wayland[657]: OpenGL renderer string:                 AMD Radeon R2 Graphics (radeonsi, kabini, LLVM 17.0.6, DRM 3.54, 6.6.21-1-lts)
мар 09 18:35:05 archlinux kwin_wayland[657]: OpenGL version string:                  4.6 (Core Profile) Mesa 24.0.2-arch1.2
мар 09 18:35:05 archlinux kwin_wayland[657]: OpenGL shading language version string: 4.60
мар 09 18:35:05 archlinux kwin_wayland[657]: Driver:                                 Unknown
мар 09 18:35:05 archlinux kwin_wayland[657]: GPU class:                              Unknown
мар 09 18:35:05 archlinux kwin_wayland[657]: OpenGL version:                         4.6
мар 09 18:35:05 archlinux kwin_wayland[657]: GLSL version:                           4.60
мар 09 18:35:05 archlinux kwin_wayland[657]: Mesa version:                           24.0.2
мар 09 18:35:05 archlinux kwin_wayland[657]: Requires strict binding:                no
мар 09 18:35:05 archlinux kwin_wayland[657]: Virtual Machine:                        no
мар 09 18:35:05 archlinux kwin_wayland[657]: Timer query support:                    yes
Comment 1 Zamundaaa 2024-03-11 23:47:21 UTC 
This is a driver bug, please report it at https://gitlab.freedesktop.org/drm/amd/-/issues

As a side note, I think your GPU can use amdgpu instead of the radeon kernel driver. It might be worth trying that out by setting the
> radeon.si_support=0 radeon.cik_support=0 amdgpu.si_support=1 amdgpu.cik_support=1
kernel boot parameters