Bug 444000 - Screen layout with 2 identical monitors resets after reboot. wayland/nvidia
Summary: Screen layout with 2 identical monitors resets after reboot. wayland/nvidia
Status: RESOLVED FIXED
Alias: None
Product: KScreen
Classification: Plasma
Component: common (show other bugs)
Version: 5.24.5
Platform: Manjaro Linux
: NOR normal
Target Milestone: ---
Assignee: kscreen-bugs-null@kde.org
URL:
Keywords: wayland-only
Depends on:
Blocks:
 
Reported: 2021-10-18 21:28 UTC by jbhorsley
Modified: 2022-12-23 22:16 UTC (History)
1 user (show)

See Also:
Latest Commit:
Version Fixed In: 5.27
Sentry Crash Report:


Attachments
kscreen .local config folder & kscreen-console output (2.72 KB, application/zip)
2021-10-18 21:28 UTC, jbhorsley
Details

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Description jbhorsley 2021-10-18 21:28:26 UTC
Created attachment 142590 [details]
kscreen .local config folder & kscreen-console output

I have 3 monitors, 2 of which are the same model. I setup the monitors in this arrangement [a][b][c] where a and c are the same model and this works fine. After restarting they are rearranged such that the a and c monitors show duplicated content: [b][ac] I then have to go in to settings and arrange them again.


STEPS TO REPRODUCE
1. Plug in 2 identical monitors
2. Setup a multi screen layout
3. restart

OBSERVED RESULT
The screens are incorrectly arranged after reboot

EXPECTED RESULT
The screens retain the layout

SOFTWARE/OS VERSIONS
Operating System: Manjaro Linux
KDE Plasma Version: 5.22.5
KDE Frameworks Version: 5.87.0
Qt Version: 5.15.2
Kernel Version: 5.14.10-1-MANJARO (64-bit)
Graphics Platform: Wayland
Processors: 32 × AMD Ryzen 9 5950X 16-Core Processor
Memory: 62.7 GiB of RAM
Graphics Processor: NVIDIA GeForce RTX 3080/PCIe/SSE2

ADDITIONAL INFORMATION
I suspect because they have the same display 'ID' it is loading the config file incorrectly.
Comment 1 jbhorsley 2021-10-30 16:39:16 UTC
My setup works fine with xorg, there the screen names have the connector on them eg: DP-1
Comment 2 jbhorsley 2022-06-29 17:44:38 UTC
Still stuck with this problem. Some updates ago it seemed to have been fixed, the displays were showing up with the connector type in the name but the most recent few have been broken again...
Comment 3 jbhorsley 2022-08-14 00:10:29 UTC
So I've had a look at the code for this and these 2 screens have identical edid data, including serial number which is just 1234567890123. So when it saves the config for these using the edid hash as an id, it saves 2 of the same name, causing the clash when it loads.
Comment 4 Nate Graham 2022-08-15 16:10:54 UTC
IIRC in this case, it's supposed to add the connector name to the information that gets hashed to determine monitor uniqueness.
Comment 5 Nate Graham 2022-11-08 23:04:43 UTC
This may have been fixed by a change to the duplicate detection algorithm in Plasma 5.26. Would you mind testing that and reporting back on whether it fixes the issue or not?

You may want to delete your kscreen configs in ~/.local/share/kscreen first to test it fresh. Thanks!
Comment 6 Bug Janitor Service 2022-11-23 05:16:06 UTC
Dear Bug Submitter,

This bug has been in NEEDSINFO status with no change for at least
15 days. Please provide the requested information as soon as
possible and set the bug status as REPORTED. Due to regular bug
tracker maintenance, if the bug is still in NEEDSINFO status with
no change in 30 days the bug will be closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

If you have already provided the requested information, please
mark the bug as REPORTED so that the KDE team knows that the bug is
ready to be confirmed.

Thank you for helping us make KDE software even better for everyone!
Comment 7 Bug Janitor Service 2022-12-08 05:15:36 UTC
This bug has been in NEEDSINFO status with no change for at least
30 days. The bug is now closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

Thank you for helping us make KDE software even better for everyone!
Comment 8 jbhorsley 2022-12-22 17:24:31 UTC
Sorry for the late reply, but this does not seem to be fixed yet. One of my monitors actually broke and I got a new one so this isn't a real issue for me anymore. It works enough to show up as a display though when plugged in and I tried it running the latest updates on manjaro, 'About this System' reports plasma version 5.26.4, the display still gets conflicted with the other identical one. Looking in the config, they both still have the same id and metadata strings.
Comment 9 Nate Graham 2022-12-23 22:16:40 UTC
I'd say there's a 99% chance this is fixed with the bug multiscreen refactor for the upcoming Plasma 5.27. Let's mark it as fixed for now, but if you find that you still experience the issue after upgrading to Plasma 5.27, please do feel free to re-open it.

Thanks a lot!