Red Hat Bugzilla – Bug 951109
kwin crashes when KDE desktop gets maximized in VNC
Last modified: 2015-11-01 20:37:11 EST
Created attachment 734209 [details]
Description of problem:
I was running KDE on a PPC64 machine in a vncserver. When I maximized the vncviewer window on my local machine, kwin crashed with the attached backtrace
Version-Release number of selected component (if applicable):
Hrm, after looking at bug #951103 , I see that these both died in the same lll_futex_wait function. Here,
Application: KWin (kwin), signal: Segmentation fault
Using host libthread_db library "/lib64/libthread_db.so.1".
155 lll_futex_wait (&cond->__data.__futex, futex_val, pshared);
[Current thread is 1 (Thread 0x3fff8cd3c290 (LWP 8166))]
When looking at a crash of a multithreaded program, the first thing to do is to identify the active thread, usually the only relevant one. Any thread stuck in something like lll_futex_wait, __lll_lock_wait etc. is NOT active. (Sadly, the wrong thread is current in GDB for some reason.)
This one is crashing in QCoreApplicationPrivate::sendPostedEvents, maybe a Qt bug?
it's crashed in libkscreen.so, Dan you can ask karsten to get account on ppc.
Assigning back to kde-workspace. This is definitely not a KScreen crash :-)
Anyway, can you please try to reproduce the crash with this Qt build?
It has a patch  that should solve crashes when using DBus from multiple threads.
Karsten cannot reproduce the crash aynmore with new qt update. reassign to correct qt component. I'm building new qt and will add it to f19 update today
Dan, good catch! thanks
qt-4.8.4-18.fc19 has been submitted as an update for Fedora 19.
* should fix your issue,
* was pushed to the Fedora 19 testing repository,
* should be available at your local mirror within two days.
Update it with:
# su -c 'yum update --enablerepo=updates-testing qt-4.8.4-18.fc19'
as soon as you are able to.
Please go to the following url:
then log in and leave karma (feedback).
qt-4.8.4-19.fc19 has been submitted as an update for Fedora 19.
it doesn't crash after update to latest version