Bug 484358

Summary:	Automatic adaptive sync fails to deactivate on exit
Product:	[Plasma] kwin	Reporter:	Austin Kauble <austinkauble>
Component:	wayland-generic	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED UPSTREAM
Severity:	normal	CC:	hoister, info, tddzmely, xaver.hugl
Priority:	NOR
Version First Reported In:	6.3.4
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Austin Kauble 2024-03-24 02:48:03 UTC

SUMMARY
Automatic adaptive sync leaves the desktop in a VRR state after closing the fullscreen application that triggered it. This persists even after disabling adaptive sync in display settings, but is fixed by switching to another refresh rate.

STEPS TO REPRODUCE
1. Enable adaptive sync
2. Observe desktop is properly vsynced still
3. Open a fullscreen application
4. Observe application enables VRR as expected
5. Close fullscreen application
5. Observe desktop is stuck in a VRR state (as seen by monitor OSD display and flickering behavior)

OBSERVED RESULT
Desktop is stuck in incorrect VRR state until the refresh rate is switched to another and back.

EXPECTED RESULT
Desktop returns to normal vsynced state after closing application

SOFTWARE/OS VERSIONS
KDE Plasma Version: 5.27.11
KDE Frameworks Version: 5.115.0
Qt Version: 5.15.12
Kernel Version: 6.7.9-204.fsync.fc39.x86_64
Graphics Platform: Wayland

ADDITIONAL INFORMATION

Comment 1 Austin Kauble 2024-03-24 02:59:44 UTC

In this bad state, switching vrr to "never" has no effect but "always" and then "never" gets back to a good state.

Comment 2 Tom Dzmelyk 2024-05-07 05:32:17 UTC

Still present with kwin 6.0.4.1

Tested on Arch (fully up to date as of today).

If the system is booted while the setting is set to Adaptive Sync=Never on both monitors the behavior is correct (even if it's bad).

If one monitor is set to adaptive sync = automatic and the other is set to never, the flicker will manifest on both monitors

I have tried minimizing every open application on every monitor, closing everything on every monitor.  Only restarting the session or adjusting the refresh rate manually in "Display Properties" after changing the refresh rate will correct the undesirable behavior.

Comment 3 Zamundaaa 2025-03-04 14:33:32 UTC

This is a driver bug, please report it to your graphics vendor (at https://gitlab.freedesktop.org/drm/amd/-/issues for AMD, https://forums.developer.nvidia.com/c/gpu-graphics/linux for NVidia)

Comment 4 Federico Dossena 2025-05-02 05:14:23 UTC

This is still happening to me on KDE 6.3.4 using an AMD GPU.

I currently have to do this almost every time I close a game or mpv.
```
kscreen-doctor output.1.vrrpolicy.always
sleep 1
kscreen-doctor output.1.vrrpolicy.automatic
```

Comment 5 Zamundaaa 2025-05-02 12:11:05 UTC

As I already wrote, this is a driver bug, which should be reported to the graphics vendors. Do not reopen this bug.