Bug 455222

Summary:	Exiting full-screen causes superfluous IDLE_NOTIFY messages in XWayland
Product:	[Plasma] kwin	Reporter:	pixelcluster
Component:	wayland-generic	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED UPSTREAM
Severity:	normal	CC:	nate
Priority:	NOR
Version First Reported In:	5.24.5
Target Milestone:	---
Platform:	Fedora RPMs
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description pixelcluster 2022-06-13 19:30:36 UTC

See also https://gitlab.freedesktop.org/xorg/xserver/-/issues/1351:
I already filed an issue in the xserver repository, but after finding that I could not reproduce this with other compositors I believe this is a KWin issue.

The issue shows for me when running Vulkan apps through RADV: If these Vulkan apps are full-screen, and I switch to another window (e. g. using Alt+Tab), these apps crash because RADV is triggering an assertion failure, which is caused by some pixmaps receiving an IDLE_NOTIFY event more than once. AFAIK windowing code is shared between RADV and anv, so I think this issue should be reproducible with Intel cards as well.

STEPS TO REPRODUCE
1. Run any Vulkan application in X11 in full-screen (maximizing the window isn't sufficient). Full-screen games using Proton/vkd3d exhibit the issue for me.
2. Switch away from the full-screen app to another window using Alt+Tab.

OBSERVED RESULT
An assertion failure is triggered inside RADV's X11 presentation handling code, making the Vulkan application crash.

EXPECTED RESULT
The application continues to run in the background.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Fedora Linux 36 (kernel 5.17.13)
KDE Plasma Version: 5.24.5
KDE Frameworks Version: 5.93.0
Qt Version: 5.15.3

Comment 1 pixelcluster 2022-06-21 09:57:22 UTC

A fix for this has been merged in XWayland (https://gitlab.freedesktop.org/xorg/xserver/-/issues/1351, https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/910).