Application: plasma-desktop (0.4)
KDE Platform Version: 4.7.3 (4.7.3)
Qt Version: 4.7.4
Operating System: Linux 3.0.0-14-generic x86_64
Distribution: Ubuntu 11.10

-- Information about the crash:
- What I was doing when the application crashed:
  I had three Okulars open, one from command-line and two by opening Thunderbird PDF attachments.  I right-clicked on the group in the Plasma panel and chose Close to close the lot, and crash! The Plasma panel bar disappeared.

- Unusual behavior I noticed:
The Plasma bar returned (good!).

The crash can be reproduced some of the time.

-- Backtrace:
Application: Plasma Desktop Shell (plasma-desktop), signal: Segmentation fault
[Current thread is 1 (Thread 0x7fe70b6967a0 (LWP 1732))]

Thread 7 (Thread 0x7fe6e91af700 (LWP 1733)):
#0  0x00007fe708167602 in socketNotifierSourceCheck (source=0x164f510) at kernel/qeventdispatcher_glib.cpp:79
#1  0x00007fe6ff500734 in g_main_context_check () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fe6ff500f82 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fe6ff501429 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007fe708167f3e in QEventDispatcherGlib::processEvents (this=0x1634f50, flags=<optimized out>) at kernel/qeventdispatcher_glib.cpp:424
#5  0x00007fe70813bcf2 in QEventLoop::processEvents (this=<optimized out>, flags=...) at kernel/qeventloop.cpp:149
#6  0x00007fe70813bef7 in QEventLoop::exec (this=0x7fe6e91aedb0, flags=...) at kernel/qeventloop.cpp:201
#7  0x00007fe70805327f in QThread::exec (this=<optimized out>) at thread/qthread.cpp:498
#8  0x00007fe70811ecbf in QInotifyFileSystemWatcherEngine::run (this=0x1633800) at io/qfilesystemwatcher_inotify.cpp:248
#9  0x00007fe708055d05 in QThreadPrivate::start (arg=0x1633800) at thread/qthread_unix.cpp:331
#10 0x00007fe70000defc in start_thread (arg=0x7fe6e91af700) at pthread_create.c:304
#11 0x00007fe70af8289d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#12 0x0000000000000000 in ?? ()

Thread 6 (Thread 0x7fe6e67a8700 (LWP 1734)):
#0  0x00007fe70af90ab6 in pthread_mutex_unlock (mutex=0xfba928) at forward.c:184
#1  0x00007fe6ff4ff687 in g_main_context_acquire () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fe6ff500d81 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fe6ff501429 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007fe708167f3e in QEventDispatcherGlib::processEvents (this=0x174c9a0, flags=<optimized out>) at kernel/qeventdispatcher_glib.cpp:424
#5  0x00007fe70813bcf2 in QEventLoop::processEvents (this=<optimized out>, flags=...) at kernel/qeventloop.cpp:149
#6  0x00007fe70813bef7 in QEventLoop::exec (this=0x7fe6e67a7db0, flags=...) at kernel/qeventloop.cpp:201
#7  0x00007fe70805327f in QThread::exec (this=<optimized out>) at thread/qthread.cpp:498
#8  0x00007fe70811ecbf in QInotifyFileSystemWatcherEngine::run (this=0xf9d1c0) at io/qfilesystemwatcher_inotify.cpp:248
#9  0x00007fe708055d05 in QThreadPrivate::start (arg=0xf9d1c0) at thread/qthread_unix.cpp:331
#10 0x00007fe70000defc in start_thread (arg=0x7fe6e67a8700) at pthread_create.c:304
#11 0x00007fe70af8289d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#12 0x0000000000000000 in ?? ()

Thread 5 (Thread 0x7fe6e1ce8700 (LWP 8441)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00007fe7080561ab in wait (time=18446744073709551615, this=0x16ac580) at thread/qwaitcondition_unix.cpp:88
#2  QWaitCondition::wait (this=<optimized out>, mutex=0x1673410, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:160
#3  0x00007fe703e50864 in ThreadWeaver::WeaverImpl::blockThreadUntilJobsAreBeingAssigned (this=0x16f8320, th=0xf74980) at ../../../threadweaver/Weaver/WeaverImpl.cpp:365
#4  0x00007fe703e52e0b in ThreadWeaver::WorkingHardState::applyForWork (this=0x1673380, th=0xf74980) at ../../../threadweaver/Weaver/WorkingHardState.cpp:71
#5  0x00007fe703e52e24 in ThreadWeaver::WorkingHardState::applyForWork (this=0x1673380, th=0xf74980) at ../../../threadweaver/Weaver/WorkingHardState.cpp:74
#6  0x00007fe703e51ccf in ThreadWeaver::ThreadRunHelper::run (this=0x7fe6e1ce7e00, parent=0x16f8320, th=0xf74980) at ../../../threadweaver/Weaver/Thread.cpp:87
#7  0x00007fe703e51d5b in ThreadWeaver::Thread::run (this=0xf74980) at ../../../threadweaver/Weaver/Thread.cpp:142
#8  0x00007fe708055d05 in QThreadPrivate::start (arg=0xf74980) at thread/qthread_unix.cpp:331
#9  0x00007fe70000defc in start_thread (arg=0x7fe6e1ce8700) at pthread_create.c:304
#10 0x00007fe70af8289d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#11 0x0000000000000000 in ?? ()

Thread 4 (Thread 0x7fe6e2bf0700 (LWP 8442)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00007fe7080561ab in wait (time=18446744073709551615, this=0x16ac580) at thread/qwaitcondition_unix.cpp:88
#2  QWaitCondition::wait (this=<optimized out>, mutex=0x1673410, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:160
#3  0x00007fe703e50864 in ThreadWeaver::WeaverImpl::blockThreadUntilJobsAreBeingAssigned (this=0x16f8320, th=0x1c0db20) at ../../../threadweaver/Weaver/WeaverImpl.cpp:365
#4  0x00007fe703e52e0b in ThreadWeaver::WorkingHardState::applyForWork (this=0x1673380, th=0x1c0db20) at ../../../threadweaver/Weaver/WorkingHardState.cpp:71
#5  0x00007fe703e51ccf in ThreadWeaver::ThreadRunHelper::run (this=0x7fe6e2befe00, parent=0x16f8320, th=0x1c0db20) at ../../../threadweaver/Weaver/Thread.cpp:87
#6  0x00007fe703e51d5b in ThreadWeaver::Thread::run (this=0x1c0db20) at ../../../threadweaver/Weaver/Thread.cpp:142
#7  0x00007fe708055d05 in QThreadPrivate::start (arg=0x1c0db20) at thread/qthread_unix.cpp:331
#8  0x00007fe70000defc in start_thread (arg=0x7fe6e2bf0700) at pthread_create.c:304
#9  0x00007fe70af8289d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#10 0x0000000000000000 in ?? ()

Thread 3 (Thread 0x7fe6dfa94700 (LWP 8443)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00007fe7080561ab in wait (time=18446744073709551615, this=0x16ac580) at thread/qwaitcondition_unix.cpp:88
#2  QWaitCondition::wait (this=<optimized out>, mutex=0x1673410, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:160
#3  0x00007fe703e50864 in ThreadWeaver::WeaverImpl::blockThreadUntilJobsAreBeingAssigned (this=0x16f8320, th=0x1ac41a0) at ../../../threadweaver/Weaver/WeaverImpl.cpp:365
#4  0x00007fe703e52e0b in ThreadWeaver::WorkingHardState::applyForWork (this=0x1673380, th=0x1ac41a0) at ../../../threadweaver/Weaver/WorkingHardState.cpp:71
#5  0x00007fe703e52e24 in ThreadWeaver::WorkingHardState::applyForWork (this=0x1673380, th=0x1ac41a0) at ../../../threadweaver/Weaver/WorkingHardState.cpp:74
#6  0x00007fe703e51ccf in ThreadWeaver::ThreadRunHelper::run (this=0x7fe6dfa93e00, parent=0x16f8320, th=0x1ac41a0) at ../../../threadweaver/Weaver/Thread.cpp:87
#7  0x00007fe703e51d5b in ThreadWeaver::Thread::run (this=0x1ac41a0) at ../../../threadweaver/Weaver/Thread.cpp:142
#8  0x00007fe708055d05 in QThreadPrivate::start (arg=0x1ac41a0) at thread/qthread_unix.cpp:331
#9  0x00007fe70000defc in start_thread (arg=0x7fe6dfa94700) at pthread_create.c:304
#10 0x00007fe70af8289d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#11 0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7fe6df293700 (LWP 8444)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00007fe7080561ab in wait (time=18446744073709551615, this=0x16ac580) at thread/qwaitcondition_unix.cpp:88
#2  QWaitCondition::wait (this=<optimized out>, mutex=0x1673410, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:160
#3  0x00007fe703e50864 in ThreadWeaver::WeaverImpl::blockThreadUntilJobsAreBeingAssigned (this=0x16f8320, th=0x1725640) at ../../../threadweaver/Weaver/WeaverImpl.cpp:365
#4  0x00007fe703e52e0b in ThreadWeaver::WorkingHardState::applyForWork (this=0x1673380, th=0x1725640) at ../../../threadweaver/Weaver/WorkingHardState.cpp:71
#5  0x00007fe703e52e24 in ThreadWeaver::WorkingHardState::applyForWork (this=0x1673380, th=0x1725640) at ../../../threadweaver/Weaver/WorkingHardState.cpp:74
#6  0x00007fe703e51ccf in ThreadWeaver::ThreadRunHelper::run (this=0x7fe6df292e00, parent=0x16f8320, th=0x1725640) at ../../../threadweaver/Weaver/Thread.cpp:87
#7  0x00007fe703e51d5b in ThreadWeaver::Thread::run (this=0x1725640) at ../../../threadweaver/Weaver/Thread.cpp:142
#8  0x00007fe708055d05 in QThreadPrivate::start (arg=0x1725640) at thread/qthread_unix.cpp:331
#9  0x00007fe70000defc in start_thread (arg=0x7fe6df293700) at pthread_create.c:304
#10 0x00007fe70af8289d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#11 0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7fe70b6967a0 (LWP 1732)):
[KCrash Handler]
#6  isNull (this=0x0) at /usr/include/qt4/QtCore/qsharedpointer_impl.h:568
#7  operator! (this=0x0) at /usr/include/qt4/QtCore/qsharedpointer_impl.h:574
#8  TaskManager::TaskItem::task (this=0x1e68e20) at ../../../libs/taskmanager/taskitem.cpp:113
#9  0x00007fe6f165a112 in WindowTaskItem::publishIconGeometry (this=0x1aced10) at ../../../../../plasma/desktop/applets/tasks/windowtaskitem.cpp:120
#10 0x00007fe6f1668b7c in AbstractTaskItem::timerEvent (this=0x1aced10, event=<optimized out>) at ../../../../../plasma/desktop/applets/tasks/abstracttaskitem.cpp:439
#11 0x00007fe708153789 in QObject::event (this=0x1aced10, e=<optimized out>) at kernel/qobject.cpp:1181
#12 0x00007fe707b0b89b in QGraphicsWidget::event (this=0x1aced10, event=0x7fff3fb7ba10) at graphicsview/qgraphicswidget.cpp:1455
#13 0x00007fe7074ed424 in notify_helper (e=0x7fff3fb7ba10, receiver=0x1aced10, this=0xdb0590) at kernel/qapplication.cpp:4486
#14 QApplicationPrivate::notify_helper (this=0xdb0590, receiver=0x1aced10, e=0x7fff3fb7ba10) at kernel/qapplication.cpp:4458
#15 0x00007fe7074f2291 in QApplication::notify (this=0xda5240, receiver=0x1aced10, e=0x7fff3fb7ba10) at kernel/qapplication.cpp:4365
#16 0x00007fe708deb126 in KApplication::notify (this=0xda5240, receiver=0x1aced10, event=0x7fff3fb7ba10) at ../../kdeui/kernel/kapplication.cpp:311
#17 0x00007fe70813cafc in QCoreApplication::notifyInternal (this=0xda5240, receiver=0x1aced10, event=0x7fff3fb7ba10) at kernel/qcoreapplication.cpp:787
#18 0x00007fe708169d62 in sendEvent (event=0x7fff3fb7ba10, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#19 QTimerInfoList::activateTimers (this=0xdb3f60) at kernel/qeventdispatcher_unix.cpp:603
#20 0x00007fe708167538 in timerSourceDispatch (source=<optimized out>) at kernel/qeventdispatcher_glib.cpp:184
#21 idleTimerSourceDispatch (source=<optimized out>) at kernel/qeventdispatcher_glib.cpp:231
#22 0x00007fe6ff500a5d in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#23 0x00007fe6ff501258 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#24 0x00007fe6ff501429 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#25 0x00007fe708167ed6 in QEventDispatcherGlib::processEvents (this=0xd12f40, flags=<optimized out>) at kernel/qeventdispatcher_glib.cpp:422
#26 0x00007fe70759507e in QGuiEventDispatcherGlib::processEvents (this=<optimized out>, flags=<optimized out>) at kernel/qguieventdispatcher_glib.cpp:204
#27 0x00007fe70813bcf2 in QEventLoop::processEvents (this=<optimized out>, flags=...) at kernel/qeventloop.cpp:149
#28 0x00007fe70813bef7 in QEventLoop::exec (this=0x7fff3fb7bca0, flags=...) at kernel/qeventloop.cpp:201
#29 0x00007fe708140789 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1064
#30 0x00007fe70b2811a3 in kdemain (argc=1, argv=0x7fff3fb7c088) at ../../../../plasma/desktop/shell/main.cpp:120
#31 0x00007fe70aec230d in __libc_start_main (main=0x400640 <main(int, char**)>, argc=1, ubp_av=0x7fff3fb7c088, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fff3fb7c078) at libc-start.c:226
#32 0x0000000000400671 in _start ()

This bug may be a duplicate of or related to bug 287740.

Possible duplicates by query: bug 288954, bug 288894, bug 288874, bug 288866, bug 288818.

Reported using DrKonqi