Bug 345241

Summary: KDE shell crashed After Modifying Display Settings to Disable Two External Monitors
Product: [Plasma] plasmashell Reporter: David Green <crokett>
Component: generic-multiscreenAssignee: Aleix Pol <aleixpol>
Status: RESOLVED WORKSFORME    
Severity: major CC: kde, mklapetek, notmart, plasma-bugs-null
Priority: NOR    
Version First Reported In: 5.2.1   
Target Milestone: 1.0   
Platform: Other   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: backtrace created after kdeshell crash

Description David Green 2015-03-16 23:30:19 UTC 
I used Display Management tool to turn off two external monitors prior to suspending my laptop, and kdeshell crashed.

Reproducible: Sometimes

Steps to Reproduce:
1.  Open System Settings ->Display -> Manage Displays 
2.  Change Multiple Displays to either enable or disable external displays
3.  Apply Settings

Actual Results:  
External Monitors shut off.  Image on laptop screen was shifted left so only about 1/4 of normal desktop was visible.  There was black on the rest of my laptop screen.  Mouse pointer would not move and keyboard was not responsive.

I changed to text based terminal via Alt+F2, used pm-suspend command to suspend.  When I resumed the laptop from suspend, kdeshell had crashed but image was correct on laptop screen

Expected Results:  
External displays would be turned off, image would display correctly on laptop screen

I have a stack trace but it was too long to place here.  I can send tarball of stack trace if requred.
Comment 1 David Green 2015-03-16 23:46:40 UTC 
Created attachment 91589 [details]
backtrace created after kdeshell crash
Comment 2 David Green 2015-03-16 23:46:59 UTC 
attached backtrace
Comment 3 Marco Martin 2015-03-17 15:48:06 UTC 
hmm, every single thread in the bt seems in waiting state?
Comment 4 David Edmundson 2015-03-27 16:06:59 UTC 
Not thread 2, pasting inline.

Thread 2 (Thread 0x7fc9e67fe700 (LWP 12697)):
[KCrash Handler]
#5  0x00007fcb14510f6d in __strstr_sse2_unaligned () at /lib64/libc.so.6
#6  0x00007fcb1adf55ca in QSGRenderContext::initialize(QOpenGLContext*) () at /lib64/libQt5Quick.so.5
#7  0x00007fcb1ae14209 in QSGRenderThread::run() () at /lib64/libQt5Quick.so.5
#8  0x00007fcb150fa4ce in QThreadPrivate::start(void*) () at /lib64/libQt5Core.so.5
#9  0x00007fcb1425752a in start_thread () at /lib64/libpthread.so.0
#10 0x00007fcb1456c22d in clone () at /lib64/libc.so.6


What version of Qt are you running?
Comment 5 Martin Klapetek 2016-02-03 20:06:14 UTC 
No response for almost a year, assuming fixed.

If this issue still happens to you, please try upgrading your Qt to at least 5.5.1
and reopen this bug if you can still reproduce.

Thank you