Bug 448173

Summary: One or both dual monitors powers off after login to Wayland KDE
Product: [Plasma] KScreen Reporter: SP <scp.stjohn>
Component: commonAssignee: kscreen-bugs-null <kscreen-bugs-null>
Status: RESOLVED DUPLICATE    
Severity: grave CC: nate, notmart, xaver.hugl
Priority: NOR Keywords: accessibility, multiscreen, wayland
Version: 5.22.4   
Target Milestone: ---   
Platform: Fedora RPMs   
OS: Linux   
Latest Commit: Version Fixed In:

Description SP 2022-01-09 17:46:11 UTC
STEPS TO REPRODUCE
1. Boot computer
2.  Arrive at SDDM login screens with both monitors working
3. Login to KDE

OBSERVED RESULT
Erratically one or both monitors immediately powers off on login to Wayland KDE from SDDM.  It is normally one screen but occasionally both.  This is remedied with a reboot though it sometimes takes a few reboots before both both screens appear during login to KDE Plasma.

EXPECTED RESULT
Monitors should not power off during login to Wayland KDE


SOFTWARE/OS VERSIONS

Linux Kernel: 5.15.12-200.fc35.x86_64
KDE Plasma Version: 5.23.4
KDE Frameworks Version: 5.89.0
Qt Version: 5.15.2
Graphics Platform: Wayland

ADDITIONAL INFORMATION

This problem occurs on two computers with the same configuration.  One computer uses Asus monitors and the other Samsung monitors.  (So this prolem is not monitor specific.)
Graphics Card AMD/ATI Tonga Pro Radeon R9 38 series
Kernel module amdgpu
OpenGL Version 4.6 Mesa 21.3.3
Processors 8 x Intel Core i7-3770 CPU @ 3.40FHz
Memory 16GB
Comment 1 Marco Martin 2022-01-13 09:32:10 UTC
what does the screen systemsetting module say? in there both monitors are configured to be enabled?
Comment 2 SP 2022-01-13 16:05:09 UTC
(In reply to Marco Martin from comment #1)
> what does the screen systemsetting module say? in there both monitors are
> configured to be enabled?

Yes both monitors are, of course, enabled in the Display Configuration module in System Settings. Both are Asus Monitors, VS248 and VE248 set at 1920 x 1080 screen resolution.  This problem does not relate to the monitors as exactly the same problem happens on another computer with the identical video card and other physical attributes albeit with Samsung monitors.  
This has also been reported as Bug 448220 assigned to KWin, @Vlad Zahorodnii reports there, "I see this issue from time to time with Xorg in SDDM and I saw this issue in 5.23. After reworking how kwin_wayland searches for working output configuration, the issue seems to be gone. Please reopen this bug report if you can reproduce this bug with 5.24 beta or just 5.14."
So if this is indeed the case, hopefully the issue will be resolved when 5.24 is released in February.  If you search the web there are multiple reports of woes with dual monitors using KDE Plasma.
Comment 3 SP 2022-02-18 19:45:04 UTC
I have now installed  kde plasma packages 5.24.1-1.fc35 on both computers with dual displays but the same problem outlined in my earlier bug report persist.  So this has not been resolved.  Please let me know of any information I can provide to assist.
Comment 4 Zamundaaa 2022-02-18 19:56:58 UTC
Let's keep it to one bug report

*** This bug has been marked as a duplicate of bug 448220 ***