https://bugs.kde.org/show_bug.cgi?id=505496
Bug ID: 505496
Summary: KWin/Wayland ignores "video=" kernel argument, fails
to create custom resolution that works in X11
Classification: Plasma
Product: kwin
Version First unspecified
Reported In:
Platform: Fedora RPMs
OS: Linux
Status: REPORTED
Severity: normal
Priority: NOR
Component: wayland-generic
Assignee: [email protected]
Reporter: [email protected]
Target Milestone: ---
Created attachment 182207
--> https://bugs.kde.org/attachment.cgi?id=182207&action=edit
This is the EDID I made and tried to make run.
I am trying to use a secondary monitor at its native resolution and refresh
rate (1360x768 @ 75Hz), which works perfectly on Windows. On my current system,
I cannot get this mode to work in the Plasma Wayland session, but I have proven
that it works correctly in a Plasma X11 session.
System Information:
OS: Bazzite (Fedora-based immutable OS)
Desktop Environment: KDE Plasma
Windowing System: Wayland
GPU: AMD (amdgpu driver)
Monitor Connection: DP-2
Steps to Reproduce in Wayland (What Fails):
Set the kernel argument video=DP-2:1360x768eD@75 using rpm-ostree kargs.
Reboot into a Plasma Wayland session.
Check available modes via System Settings or kscreen-doctor -o.
Actual Results (in Wayland):
The 1360x768 @ 75Hz mode is not created. kscreen-doctor only shows a 60Hz mode
available:
Output: 1 DP-2
Modes: 1:1360x768@60*! 2:1280x720@60 3:1024x768@75 ...
The video= kernel argument is completely ignored by the Wayland session.
Attempts to use a custom EDID file via drm.edid_firmware also failed.
Expected Results:
The 1360x768@75Hz mode should be created and available for selection.
Additional Information (Proof it Works in X11):
This is NOT a hardware or driver limitation. If I log into a Plasma (X11)
session on the same machine, I can successfully create and apply the mode with
xrandr:
Bash
# 1. Create the mode
xrandr --newmode "1360x768_75" 109.00 1360 1440 1584 1808 768 771 781 805
-hsync +vsync
# 2. Add the mode to the output
xrandr --addmode DP-2 "1360x768_75"
# 3. Apply the mode
xrandr --output DP-2 --mode "1360x768_75"
This procedure works perfectly, and the monitor runs at 75Hz as expected in
X11. This strongly suggests the issue is with how KWin handles or validates
modes in the Wayland session.
--
You are receiving this mail because:
You are watching all bug changes.
