Bug 453642 - Multiple monitors with identical EDID hashes reset configuration and mirror screens after sleep
Summary: Multiple monitors with identical EDID hashes reset configuration and mirror s...
Status: RESOLVED FIXED
Alias: None
Product: KScreen
Classification: Plasma
Component: common (other bugs)
Version First Reported In: 5.24.5
Platform: Arch Linux Linux
: NOR normal
Target Milestone: ---
Assignee: kscreen-bugs-null@kde.org
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2022-05-11 00:22 UTC by Isaac
Modified: 2022-10-14 09:44 UTC (History)
5 users (show)

See Also:
Latest Commit:
Version Fixed/Implemented In: 5.26.0
Sentry Crash Report:


Attachments
qdbus org.kde.KWin /KWin supportInformation (6.71 KB, text/plain)
2022-05-11 00:22 UTC, Isaac
Details
Screenshot of the screen configuration (21.43 KB, image/png)
2022-08-18 13:49 UTC, tobias.kuendig
Details

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Description Isaac 2022-05-11 00:22:17 UTC
Created attachment 148721 [details]
qdbus org.kde.KWin /KWin supportInformation

SUMMARY
When having multiple monitors connected under a wayland session, after the screens time out, the monitor configuration resets. Both monitors will be mirrored instead of extended, and the framerate will be set to 60Hz instead of 144Hz.

STEPS TO REPRODUCE
1. Setup two 1440p monitors at 144Hz, connected via displayport. Have one directly to the right of the other.
2. Enable Screen Energy Savings under Power Management and allow screens to go blank.
3. Wake up computer by touching the keyboard or mouse. 
4. Observe that monitors are now mirrored instead of extended and that the frame rate is now set to 60Hz.

OBSERVED RESULT
Monitors are now mirrors of each other with reduced framerate of 60Hz.

EXPECTED RESULT
After waking up, the monitors should retain the configuration setup previously.

SOFTWARE/OS VERSIONS

Operating System: Arch Linux
KDE Plasma Version: 5.24.5
KDE Frameworks Version: 5.93.0
Qt Version: 5.15.3
Kernel Version: 5.17.5-zen1-1-zen (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 7 1700X Eight-Core Processor
Memory: 15.6 GiB of RAM
Graphics Processor: AMD Radeon RX Vega

ADDITIONAL INFORMATION
KDE support information attached.
Comment 1 Isaac 2022-05-13 18:00:18 UTC
I think an additional point that might be causing this bug is that both monitors are identified as "DP_FREESYNC 1" in the Display Configuration settings tab. They are identically named, and I think this is breaking the configuration upon waking. 

An additional point: The bug is not present when the system goes to sleep, only when the monitors are turned off for power savings.
Comment 2 tobias.kuendig 2022-08-18 13:49:24 UTC
I can confirm this problem. I too have two screens connected via Display Port that use the same identification string in the system settings screen.

Operating System: KDE neon 5.25
KDE Plasma Version: 5.25.4
KDE Frameworks Version: 5.96.0
Qt Version: 5.15.5
Kernel Version: 5.18.15-051815-generic (64-bit)
Graphics Platform: Wayland
Processors: 24 × 12th Gen Intel® Core™ i9-12900K
Memory: 62.6 GiB of RAM
Graphics Processor: Mesa Intel® Graphics
Manufacturer: Micro-Star International Co., Ltd.
Product Name: MS-7D25
System Version: 1.0
Comment 3 tobias.kuendig 2022-08-18 13:49:46 UTC
Created attachment 151401 [details]
Screenshot of the screen configuration
Comment 4 David Edmundson 2022-10-14 09:44:23 UTC
This is potentially fixed with https://invent.kde.org/plasma/kscreen/-/merge_requests/123 which is in Plasma 5.26

Please reopen if a bug persists.