Bug 495946

Summary:	On X11, unresponsive and partially painted desktop after unlocking screen
Product:	[Plasma] kwin	Reporter:	Tristan Miller <psychonaut>
Component:	general	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	REPORTED ---
Severity:	normal	CC:	nate
Priority:	NOR	Keywords:	X11-only
Version First Reported In:	6.2.2
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description Tristan Miller 2024-11-07 23:46:58 UTC

When unlocking the screen, about 20% of the time, I don't get taken back to my desktop environment as usual.  Instead, some or all elements of the desktop are missing (usually the panel, and sometimes also window title bars or maybe entire windows) and the system is generally unresponsive to keystrokes or mouse clicks.  However, if I re-lock the screen with my usual keyboard shortcut, and then immediately unlock it again, everything works as expected.

I found other bug reports here concerning problems unlocking after waking the computer from sleep.  However, in my case putting the computer to sleep is not necessary to trigger the bug.  It's sufficient to simply lock the desktop, wait several minutes or hours without suspending the computer, and then unlock it again.

Reproducibility: Sometimes

Steps to reproduce:

1. Lock the screen.
2. Unlock the screen.

Observed result:

3. The desktop is only partially displayed and is unresponsive to keystrokes and mouse clicks.

Expected result:

3. The desktop should be restored with full visibility and functionality.

Software/OS versions:

OS: openSUSE Tumbleweed
KDE Plasma Version: 6.2.2
KDE Frameworks Version: 6.7.0
Qt Version: 6.8.0
Graphics platform: X11

Comment 1 Nate Graham 2024-11-08 22:38:12 UTC

What GPU are you using? Does it also happen on Wayland?

Comment 2 Tristan Miller 2024-11-10 15:53:07 UTC

(In reply to Nate Graham from comment #1)
> What GPU are you using? Does it also happen on Wayland?

I'm using an onboard Intel HD Graphics 630.

I haven't tested Wayland and am not sure if I could run it long enough to reproduce the bug.  (Last I checked it had too many showstopping or dealbreaking bugs.)

Comment 3 Nate Graham 2024-11-12 15:44:31 UTC

Could you try again?

Comment 4 Tristan Miller 2024-11-12 17:55:34 UTC

I'm trying now.  The other bugs are as annoying as ever.  I'll keep up with it for a while to see if I can reproduce the problem.

Comment 5 Tristan Miller 2024-11-25 20:26:21 UTC

I used Wayland for about 10 days and didn't observe the bug.  By contrast, I usually do see it once or twice a week when using X11.  So I think we can assume for now that the problem occurs only with X11.

Comment 6 Nate Graham 2024-11-26 21:13:07 UTC

Thanks a lot for such exhaustive testing. Really appreciated.

Comment 7 TraceyC 2025-02-24 17:59:14 UTC

Adding the x11-only keyword