Bug 491128

Summary:	With NVIDIA GPU, plasmashell hangs when unfocusing a window overlapping "Dodge Windows" panel
Product:	[Plasma] plasmashell	Reporter:	Dimitrys <demetresmeliates+kde>
Component:	general	Assignee:	Plasma Bugs List <plasma-bugs-null>
Status:	RESOLVED UPSTREAM
Severity:	normal	CC:	kde, nate, xaver.hugl
Priority:	NOR
Version First Reported In:	6.1.3
Target Milestone:	1.0
Platform:	Fedora RPMs
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Dimitrys 2024-08-01 15:10:58 UTC

-SUMMARY-
The KDE Plasma Shell freezes when a window is dragged to hide a panel with the "Dodge Windows" setting, and the user attempts to unfocus the window.

-STEPS TO REPRODUCE-
0.5. Have a panel with the setting "Dodge Windows"
1. Drag a window to the panel to auto hide the panel. The panel should be hidden.
2. Click anywhere outside of the window. 
3. Watch the Shell freeze.
4. Move the pointer down to the hidden panel to unhide it.
5. Shell becomes responsive again.

-OBSERVED RESULT-
A panel with the "Dodge windows" setting is active (see attachment). When a window is positioned to hide the panel, the shell becomes unresponsive if the user attempts to unfocus the window by clicking on the desktop or another application. All user input is frozen. Unhiding the panel restores shell responsiveness, and all previously inputted commands are executed simultaneously.


-EXPECTED RESULT-
The system should remain responsive regardless of whether the panel is visible or hidden by other windows.

-SOFTWARE/OS VERSIONS-
Windows: -
macOS: -
Linux / KDE Plasma: 6.9.12-200.fc40.x86_64 (64-bit) / 6.1.3
KDE Plasma Version: 6.1.3
KDE Frameworks Version: 6.4.0
Qt Version: 6.7.2

-ADDITIONAL INFORMATION-
WM: KWin (Wayland)
GPU: NVIDIA GeForce GTX 1070 [Discrete]

Comment 1 Dimitrys 2024-08-01 15:16:21 UTC

Attachment at google drive: https://drive.google.com/file/d/1ROuBdsKYiMSb6Qd_cvmGj1vQ-XvYvp5L/view?usp=drive_link

Comment 2 Nate Graham 2024-08-01 18:25:23 UTC

Cannot reproduce the issue with current git master. I think this is very likely an NVIDIA GPU driver issue.

If so, you should be able to reproduce the issue with a new clear user account with the only customization being to use "Dodge Windows" for the default panel. Can you try that?

Comment 3 Dimitrys 2024-08-01 19:27:19 UTC

(In reply to Nate Graham from comment #2)
> Cannot reproduce the issue with current git master. I think this is very
> likely an NVIDIA GPU driver issue.
> 
> If so, you should be able to reproduce the issue with a new clear user
> account with the only customization being to use "Dodge Windows" for the
> default panel. Can you try that?

I think you might be correct, but cannot verify how. I changed the user the issue still replicates. Switched to X11 the issue disappeared. Made a VM the issue did NOT reappear. I am really sure I installed the drivers correctly.

Comment 4 Zamundaaa 2024-08-06 17:31:22 UTC

Th is is a known NVidia driver bug with explicit sync. It'll be fixed in the 560 driver IIRC