Bug 434452

Summary:	Segfault when restarting pipewire while window preview is shown
Product:	[Plasma] kwin	Reporter:	Alois Wohlschlager <alois1>
Component:	wayland-generic	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED DUPLICATE
Severity:	crash	CC:	kde, nate
Priority:	NOR
Version First Reported In:	git master
Target Milestone:	---
Platform:	Compiled Sources
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Alois Wohlschlager 2021-03-15 17:38:20 UTC

SUMMARY

When window previews are shown (e.g. by hovering over the task bar or operating Alt-Tab), and pipewire is restarted, kwin_wayland segfaults.

STEPS TO REPRODUCE
1. Open Konsole, hover over its entry in taskbar
2. systemctl --user restart pipewire.service

OBSERVED RESULT
kwin_wayland crashes with segmentation fault

EXPECTED RESULT
kwin_wayland keeps running, maybe the window previews disappear or flicker

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 5.21.1
KDE Frameworks Version: 5.79.0
Qt Version: 5.15.2

ADDITIONAL INFORMATION
When the window preview is shown, kwin_wayland starts another thread. This thread exits before the main thread receives SIGSEGV. Unfortunately, this extra thread seems to have caused memory errors affecting the main thread, since the stack trace seems very corrupted.

The crash is always reproducible.

(ins)(gdb) bt
#0  0x00007f33c1573610 in  ()
#1  0x0000000002827758 in  ()
#2  0x0000000002827758 in  ()
#3  0x0000000000000000 in  ()

Comment 1 Alois Wohlschlager 2021-04-05 11:59:46 UTC

*** Bug 435371 has been marked as a duplicate of this bug. ***

Comment 2 Alois Wohlschlager 2021-04-05 12:02:00 UTC

The same crash also happens for other situations where KWin is transporting screen content over Pipewire.

Comment 3 Vlad Zahorodnii 2021-04-07 19:35:29 UTC


*** This bug has been marked as a duplicate of bug 428268 ***