Bug 431417

Summary:	Plasma crash when dual screens turned off
Product:	[Plasma] plasmashell	Reporter:	Curtis <kdebugs>
Component:	generic-multiscreen	Assignee:	Aleix Pol <aleixpol>
Status:	RESOLVED FIXED
Severity:	crash	CC:	nate, plasma-bugs
Priority:	NOR	Keywords:	drkonqi
Version:	5.19.5
Target Milestone:	1.0
Platform:	Ubuntu
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description Curtis 2021-01-11 03:19:58 UTC

Application: plasmashell (5.19.5)

Qt Version: 5.14.2
Frameworks Version: 5.74.0
Operating System: Linux 5.8.0-36-generic x86_64
Windowing system: X11
Distribution: Ubuntu 20.10

-- Information about the crash:
- What I was doing when the application crashed:
Dual monitors - when the screens have the power switched off (using the power button on the front of the monitor) and I turn them back on after some amount of time, plasmashell has crashed. The primary monitor displays large grey macroblocks and nothing else. Cycling the monitor power via the front button will resolve this, however I manually need to restart plasmashell from the alt-f2 menu

The crash can be reproduced sometimes.

-- Backtrace:
Application: Plasma (plasmashell), signal: Segmentation fault

[KCrash Handler]
#4  0x00007f5654f9d614 in QQuickWindow::maybeUpdate() () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#5  0x00007f56534de651 in QObject::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f5653fbe013 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#7  0x00007f56534b21ca in QCoreApplication::notifyInternal2(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f56534b4bc1 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007f565350a1c7 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#10 0x00007f565193f4db in g_main_context_dispatch () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#11 0x00007f565193f788 in ?? () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#12 0x00007f565193f853 in g_main_context_iteration () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#13 0x00007f5653509843 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#14 0x00007f56534b0a4b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#15 0x00007f56534b8fc6 in QCoreApplication::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#16 0x000055c2a14b184b in ?? ()
#17 0x00007f5652e62cb2 in __libc_start_main (main=0x55c2a14b0c90, argc=1, argv=0x7fff9ff86258, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fff9ff86248) at ../csu/libc-start.c:314
#18 0x000055c2a14b1a2e in _start ()
[Inferior 1 (process 147685) detached]

Possible duplicates by query: bug 431401, bug 431375, bug 431304, bug 431280, bug 431077.

Reported using DrKonqi

Comment 1 Nate Graham 2021-01-11 23:29:34 UTC

Hmm, backtrace is 100% in non-KDE code. :/

Comment 2 Curtis 2021-01-12 17:59:19 UTC

Apologies, I'm new to the crash reporter and am not sure how to read which code or library is the issue. Is the backtrace not recording the full thing, or does the backtrace indicate the issue is outside of KDE?

When this issue happens plasmashell is the only thing that's affected, all other applications running at the time are still running and if I Alt-F2 "plasmashell" to restart it then the system works fine again until I shut the monitors off (for overnight), then turn them on again in the morning.

Comment 3 Nate Graham 2021-01-12 19:02:12 UTC

That wasn't a comment directed at you. :) Just that with no KDE code in the backtrace, I'm not sure how to proceed. It might be a pure Qt issue, or an issue in unrelated KDE code that's triggering a Qt issue.

Comment 4 Nate Graham 2021-08-17 02:00:56 UTC

I do notice you're still using Plasma 5.19.5, which is no longer supported. Any chance you can upgrade to 5.22 and see if it still happens?

Comment 5 Curtis 2021-08-17 17:44:33 UTC

Running KDE under Kubuntu - recent upgrade to 21.04 has put me up to "plasmashell 5.21.4"

Can confirm this is no longer happening (though I have also upgraded both monitors, previously they were a 1920x1200 main and a 1600x1200 secondary. Now they are 3440x1440 main and 2560x1440 secondary). I doubt the change in monitors was the result but maybe the old 4:3 scale was some weird edge case?

Either way this hasn't happened for a while, I appreciate the comments and follow up, please feel free to close this out.

Comment 6 Nate Graham 2021-08-17 17:49:33 UTC

Thank you for checking!