Bug 506308

Summary:	The cursor stutters and doesn't move smoothly when updated to Plasma 6.4.0
Product:	[Plasma] kwin	Reporter:	Rikka <rikka>
Component:	libinput	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED UPSTREAM
Severity:	normal	CC:	kdedev
Priority:	NOR	Keywords:	regression
Version First Reported In:	6.4.0
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:
Attachments:	The video shows how cursor move

Description Rikka 2025-06-28 10:52:37 UTC

Created attachment 182754 [details]
The video shows how cursor move

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SUMMARY


STEPS TO REPRODUCE
Update to 6.4.0

OBSERVED RESULT
The cursor stutters and doesn't move smoothly

EXPECTED RESULT
The cursor moves smoothly

SOFTWARE/OS VERSIONS
Operating System: ArchLinux
KDE Plasma Version: 6.4.1
KDE Frameworks Version: 6.15.0
Qt Version: 6.9.1
Kernel Version: 6.15.2-1-cachyos (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 7 8845HS w/ Radeon 780M Graphics
Memory: 32 GiB of RAM (30.6 GiB usable)
Graphics Processor: AMD Radeon 780M Graphics


ADDITIONAL INFORMATION
Work normally in some apps like Firefox, Chromium, Steam and all games
This issue only started happening after the upgrade to Plasma 6.4.0

Comment 1 TraceyC 2025-07-03 00:18:27 UTC

Thanks for the bug report, and the screen recording. Can I ask you to get some system logs, save them to a file, and attach that file to this bug report?

To get the logs for your current session, and save them to a file, use this:

 journalctl -b > ~/log.txt

Thanks

Comment 2 Rikka 2025-07-03 17:43:57 UTC

(In reply to TraceyC from comment #1)
> Thanks for the bug report, and the screen recording. Can I ask you to get
> some system logs, save them to a file, and attach that file to this bug
> report?
> 
> To get the logs for your current session, and save them to a file, use this:
> 
>  journalctl -b > ~/log.txt
> 
> Thanks

Actually there isn’t any helpful information in journal.
I tried disabling VRR and the problem is fixed.

Comment 3 TraceyC 2025-07-03 19:01:44 UTC

Thanks for the reply. It sounds like this is a problem with the AMD / mesa drivers then. Please read https://docs.mesa3d.org/bugs.html and submit a bug report for the Mesa developers. Thanks!