Application: kontact (4.14.3)
KDE Platform Version: 4.14.13
Qt Version: 4.8.6
Operating System: Linux 3.13.0-74-generic x86_64
Distribution: Ubuntu 14.04.3 LTS

-- Information about the crash:
- What I was doing when the application crashed:

1. On the left I have my folders view, say there are 20 folders. In the middle I have my message list, on the right a certain message text is shown.
2. Using the mouse, I grab this message from the list and move it into the one folder, say it is the 9th counted from the top. 
3. When I would release the mouse button above the 9th folder, something would happen in all folders from the 1st to the 9th, indicated by an icon with a a rotating arrow, which is shown instead of the normal folder icon.

After 5-15 seconds, 
a) the activity is over, I can work normally
b) kmail would crash

I cannot say when point 3 will happen, It seems to be in the beginning of daily work. However, it is not each time (each day and it may happen more than one time per day. For instance, if (3) happens, and case (a) happens,  I would move another message into folder 12, then the same (3) would happen again.  I think that  it would not, when I move a message to say folder 4 (a folder above folder 9). But I'm not sure at the moment.

I tried to differentiate the issue and move messages by using the context menu. I never experienced the problem this way. Maybe it is a problem with the mouse? HOwever, only in kmail I have unexpected behaviour.

MAybe s.o. can give me a int where to watch, or what to triy out.

The crash can be reproduced sometimes.

-- Backtrace:
Application: Kontact (kontact), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f8e9be70800 (LWP 4748))]

Thread 5 (Thread 0x7f8e7ae7f700 (LWP 4749)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007f8e96c1c81d in WTF::TCMalloc_PageHeap::scavengerThread() () from /usr/lib/x86_64-linux-gnu/libQtWebKit.so.4
#2  0x00007f8e96c1c859 in WTF::TCMalloc_PageHeap::runScavengerThread(void*) () from /usr/lib/x86_64-linux-gnu/libQtWebKit.so.4
#3  0x00007f8e9333d182 in start_thread (arg=0x7f8e7ae7f700) at pthread_create.c:312
#4  0x00007f8e993f047d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111

Thread 4 (Thread 0x7f8e3a57c700 (LWP 4750)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007f8e9695d20d in JSC::BlockAllocator::blockFreeingThreadMain() () from /usr/lib/x86_64-linux-gnu/libQtWebKit.so.4
#2  0x00007f8e96c4bfd6 in WTF::wtfThreadEntryPoint(void*) () from /usr/lib/x86_64-linux-gnu/libQtWebKit.so.4
#3  0x00007f8e9333d182 in start_thread (arg=0x7f8e3a57c700) at pthread_create.c:312
#4  0x00007f8e993f047d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111

Thread 3 (Thread 0x7f8e2ad84700 (LWP 4756)):
#0  0x00007f8e99b69b50 in testAndSetOrdered (newValue=0, expectedValue=1, this=0x1a3de90) at ../../include/QtCore/../../src/corelib/arch/qatomic_x86_64.h:145
#1  testAndSetRelease (newValue=0, expectedValue=1, this=0x1a3de90) at ../../include/QtCore/../../src/corelib/arch/qatomic_x86_64.h:272
#2  unlockInline (this=0x1a3de48) at ../../include/QtCore/../../src/corelib/thread/qmutex.h:171
#3  unlock (this=<synthetic pointer>) at ../../include/QtCore/../../src/corelib/thread/qmutex.h:121
#4  ~QMutexLocker (this=<synthetic pointer>, __in_chrg=<optimized out>) at ../../include/QtCore/../../src/corelib/thread/qmutex.h:115
#5  canWaitLocked (this=0x1a3de00) at ../../include/QtCore/private/../../../src/corelib/thread/qthread_p.h:229
#6  postEventSourcePrepare (s=0x7f8e24001350, timeout=0x7f8e2ad83c24) at kernel/qeventdispatcher_glib.cpp:270
#7  0x00007f8e92e5d68d in g_main_context_prepare () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#8  0x00007f8e92e5df03 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#9  0x00007f8e92e5e0ec in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#10 0x00007f8e99b697be in QEventDispatcherGlib::processEvents (this=0x7f8e240008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:436
#11 0x00007f8e99b3b0af in QEventLoop::processEvents (this=this@entry=0x7f8e2ad83de0, flags=...) at kernel/qeventloop.cpp:149
#12 0x00007f8e99b3b3a5 in QEventLoop::exec (this=this@entry=0x7f8e2ad83de0, flags=...) at kernel/qeventloop.cpp:204
#13 0x00007f8e99a37c5f in QThread::exec (this=<optimized out>) at thread/qthread.cpp:537
#14 0x00007f8e99a3a32f in QThreadPrivate::start (arg=0x1ad2190) at thread/qthread_unix.cpp:349
#15 0x00007f8e9333d182 in start_thread (arg=0x7f8e2ad84700) at pthread_create.c:312
#16 0x00007f8e993f047d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111

Thread 2 (Thread 0x7f8e23783700 (LWP 4767)):
#0  0x00007f8e993e312d in poll () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007f8e92e5dfe4 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f8e92e5e0ec in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f8e99b697be in QEventDispatcherGlib::processEvents (this=0x7f8e1c0008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:436
#4  0x00007f8e99b3b0af in QEventLoop::processEvents (this=this@entry=0x7f8e23782da0, flags=...) at kernel/qeventloop.cpp:149
#5  0x00007f8e99b3b3a5 in QEventLoop::exec (this=this@entry=0x7f8e23782da0, flags=...) at kernel/qeventloop.cpp:204
#6  0x00007f8e99a37c5f in QThread::exec (this=this@entry=0x26d3c00) at thread/qthread.cpp:537
#7  0x00007f8e99b1c823 in QInotifyFileSystemWatcherEngine::run (this=0x26d3c00) at io/qfilesystemwatcher_inotify.cpp:265
#8  0x00007f8e99a3a32f in QThreadPrivate::start (arg=0x26d3c00) at thread/qthread_unix.cpp:349
#9  0x00007f8e9333d182 in start_thread (arg=0x7f8e23783700) at pthread_create.c:312
#10 0x00007f8e993f047d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111

Thread 1 (Thread 0x7f8e9be70800 (LWP 4748)):
[KCrash Handler]
#6  QModelIndex (other=..., this=0x7ffe81258620) at /usr/include/qt4/QtCore/qabstractitemmodel.h:65
#7  KSelectionProxyModelPrivate::mapTopLevelToSource (this=this@entry=0x58a4fa0, row=0, column=0) at ../../kdeui/itemviews/kselectionproxymodel.cpp:1623
#8  0x00007f8e9b21eba1 in KSelectionProxyModel::mapToSource (this=0x46007a0, proxyIndex=...) at ../../kdeui/itemviews/kselectionproxymodel.cpp:2151
#9  0x00007f8e9b21a094 in KSelectionProxyModel::data (this=0x46007a0, index=..., role=34) at ../../kdeui/itemviews/kselectionproxymodel.cpp:2255
#10 0x00007f8e9838ffca in Akonadi::EntityMimeTypeFilterModel::filterAcceptsRow(int, QModelIndex const&) const () from /usr/lib/libakonadi-kde.so.4
#11 0x00007f8e9aaa203f in QSortFilterProxyModelPrivate::create_mapping (this=this@entry=0x45c3f10, source_parent=...) at itemviews/qsortfilterproxymodel.cpp:327
#12 0x00007f8e9aaa318c in QSortFilterProxyModel::rowCount (this=<optimized out>, parent=...) at itemviews/qsortfilterproxymodel.cpp:1690
#13 0x00007f8e2fd78755 in MessageList::StorageModel::rowCount(QModelIndex const&) const () from /usr/lib/libmessagelist.so.4
#14 0x00007f8e2fd3891c in MessageList::Core::Model::setStorageModel(MessageList::Core::StorageModel*, MessageList::Core::PreSelectionMode) () from /usr/lib/libmessagelist.so.4
#15 0x00007f8e2fd3961e in ?? () from /usr/lib/libmessagelist.so.4
#16 0x00007f8e99b5087a in QMetaObject::activate (sender=0x3f428f0, m=<optimized out>, local_signal_index=<optimized out>, argv=0x0) at kernel/qobject.cpp:3539
#17 0x00007f8e99b5087a in QMetaObject::activate (sender=sender@entry=0x656dc80, m=m@entry=0x7f8e99ea06a0 <QAbstractItemModel::staticMetaObject>, local_signal_index=local_signal_index@entry=13, argv=argv@entry=0x0) at kernel/qobject.cpp:3539
#18 0x00007f8e99b9a883 in QAbstractItemModel::modelReset (this=this@entry=0x656dc80) at .moc/release-shared/moc_qabstractitemmodel.cpp:250
#19 0x00007f8e99b3061e in QAbstractItemModel::reset (this=0x656dc80) at kernel/qabstractitemmodel.cpp:2913
#20 0x00007f8e99b5087a in QMetaObject::activate (sender=sender@entry=0x46007a0, m=m@entry=0x7f8e99ea06a0 <QAbstractItemModel::staticMetaObject>, local_signal_index=local_signal_index@entry=7, argv=argv@entry=0x7ffe81258de0) at kernel/qobject.cpp:3539
#21 0x00007f8e99b9a704 in QAbstractItemModel::rowsRemoved (this=this@entry=0x46007a0, _t1=..., _t2=0, _t3=4461) at .moc/release-shared/moc_qabstractitemmodel.cpp:210
#22 0x00007f8e99b3773e in QAbstractItemModel::endRemoveRows (this=this@entry=0x46007a0) at kernel/qabstractitemmodel.cpp:2487
#23 0x00007f8e9b223c20 in KSelectionProxyModelPrivate::removeRangeFromProxy (this=this@entry=0x58a4fa0, range=...) at ../../kdeui/itemviews/kselectionproxymodel.cpp:1732
#24 0x00007f8e9b224545 in KSelectionProxyModelPrivate::removeSelectionFromProxy (this=this@entry=0x58a4fa0, selection=...) at ../../kdeui/itemviews/kselectionproxymodel.cpp:1637
#25 0x00007f8e9b224b8d in KSelectionProxyModelPrivate::selectionChanged (this=<optimized out>, _selected=..., _deselected=...) at ../../kdeui/itemviews/kselectionproxymodel.cpp:1887
#26 0x00007f8e99b5087a in QMetaObject::activate (sender=sender@entry=0x2005380, m=m@entry=0x7f8e9aff0fc0 <QItemSelectionModel::staticMetaObject>, local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x7ffe812593b0) at kernel/qobject.cpp:3539
#27 0x00007f8e9aa728f7 in QItemSelectionModel::selectionChanged (this=this@entry=0x2005380, _t1=..., _t2=...) at .moc/release-shared/moc_qitemselectionmodel.cpp:165
#28 0x00007f8e9aa77f17 in QItemSelectionModel::emitSelectionChanged (this=this@entry=0x2005380, newSelection=..., oldSelection=...) at itemviews/qitemselectionmodel.cpp:1600
#29 0x00007f8e9aa78723 in QItemSelectionModel::select (this=0x2005380, selection=..., command=...) at itemviews/qitemselectionmodel.cpp:1110
#30 0x00007f8e2fd754d0 in MessageList::Pane::Private::onSelectionChanged(QItemSelection const&, QItemSelection const&) () from /usr/lib/libmessagelist.so.4
#31 0x00007f8e99b5087a in QMetaObject::activate (sender=sender@entry=0x1ee6420, m=m@entry=0x7f8e9aff0fc0 <QItemSelectionModel::staticMetaObject>, local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x7ffe81259880) at kernel/qobject.cpp:3539
#32 0x00007f8e9aa728f7 in QItemSelectionModel::selectionChanged (this=this@entry=0x1ee6420, _t1=..., _t2=...) at .moc/release-shared/moc_qitemselectionmodel.cpp:165
#33 0x00007f8e9aa77f17 in QItemSelectionModel::emitSelectionChanged (this=this@entry=0x1ee6420, newSelection=..., oldSelection=...) at itemviews/qitemselectionmodel.cpp:1600
#34 0x00007f8e9aa78723 in QItemSelectionModel::select (this=0x1ee6420, selection=..., command=...) at itemviews/qitemselectionmodel.cpp:1110
#35 0x00007f8e9844ecd5 in ?? () from /usr/lib/libakonadi-kde.so.4
#36 0x00007f8e984463b9 in ?? () from /usr/lib/libakonadi-kde.so.4
#37 0x00007f8e99b5087a in QMetaObject::activate (sender=sender@entry=0x238e180, m=m@entry=0x7f8e9aff0fc0 <QItemSelectionModel::staticMetaObject>, local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x7ffe81259c50) at kernel/qobject.cpp:3539
#38 0x00007f8e9aa728f7 in QItemSelectionModel::selectionChanged (this=this@entry=0x238e180, _t1=..., _t2=...) at .moc/release-shared/moc_qitemselectionmodel.cpp:165
#39 0x00007f8e9aa77f17 in QItemSelectionModel::emitSelectionChanged (this=this@entry=0x238e180, newSelection=..., oldSelection=...) at itemviews/qitemselectionmodel.cpp:1600
#40 0x00007f8e9aa78723 in QItemSelectionModel::select (this=0x238e180, selection=..., command=...) at itemviews/qitemselectionmodel.cpp:1110
#41 0x00007f8e9aa48430 in QListView::setSelection (this=<optimized out>, rect=..., command=...) at itemviews/qlistview.cpp:1379
#42 0x00007f8e9aa24e1a in QAbstractItemView::mousePressEvent (this=0x237d880, event=<optimized out>) at itemviews/qabstractitemview.cpp:1690
#43 0x00007f8e9a57938b in QWidget::event (this=this@entry=0x237d880, event=event@entry=0x7ffe8125a6e0) at kernel/qwidget.cpp:8372
#44 0x00007f8e9a91b04e in QFrame::event (this=0x237d880, e=0x7ffe8125a6e0) at widgets/qframe.cpp:557
#45 0x00007f8e9aa2a633 in QAbstractItemView::viewportEvent (this=0x237d880, event=0x7ffe8125a6e0) at itemviews/qabstractitemview.cpp:1644
#46 0x00007f8e99b3c646 in QCoreApplicationPrivate::sendThroughObjectEventFilters (this=this@entry=0x185ec60, receiver=receiver@entry=0x1ffdbf0, event=event@entry=0x7ffe8125a6e0) at kernel/qcoreapplication.cpp:1063
#47 0x00007f8e9a529e0c in QApplicationPrivate::notify_helper (this=this@entry=0x185ec60, receiver=receiver@entry=0x1ffdbf0, e=e@entry=0x7ffe8125a6e0) at kernel/qapplication.cpp:4563
#48 0x00007f8e9a5305dd in QApplication::notify (this=this@entry=0x7ffe8125af30, receiver=receiver@entry=0x1ffdbf0, e=e@entry=0x7ffe8125a6e0) at kernel/qapplication.cpp:4110
#49 0x00007f8e9b23480a in KApplication::notify (this=0x7ffe8125af30, receiver=0x1ffdbf0, event=0x7ffe8125a6e0) at ../../kdeui/kernel/kapplication.cpp:311
#50 0x00007f8e99b3c4dd in QCoreApplication::notifyInternal (this=0x7ffe8125af30, receiver=receiver@entry=0x1ffdbf0, event=event@entry=0x7ffe8125a6e0) at kernel/qcoreapplication.cpp:953
#51 0x00007f8e9a52fd93 in sendEvent (event=<optimized out>, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:231
#52 QApplicationPrivate::sendMouseEvent (receiver=receiver@entry=0x1ffdbf0, event=event@entry=0x7ffe8125a6e0, alienWidget=alienWidget@entry=0x1ffdbf0, nativeWidget=nativeWidget@entry=0x20942d0, buttonDown=buttonDown@entry=0x7f8e9b00f318 <qt_button_down>, lastMouseReceiver=..., spontaneous=spontaneous@entry=true) at kernel/qapplication.cpp:3178
#53 0x00007f8e9a5a49eb in QETWidget::translateMouseEvent (this=this@entry=0x20942d0, event=event@entry=0x7ffe8125aa60) at kernel/qapplication_x11.cpp:4634
#54 0x00007f8e9a5a4289 in QApplication::x11ProcessEvent (this=0x7ffe8125af30, event=event@entry=0x7ffe8125aa60) at kernel/qapplication_x11.cpp:3627
#55 0x00007f8e9a5cbb32 in x11EventSourceDispatch (s=0x1861d30, callback=0x0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#56 0x00007f8e92e5de04 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#57 0x00007f8e92e5e048 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#58 0x00007f8e92e5e0ec in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#59 0x00007f8e99b697a1 in QEventDispatcherGlib::processEvents (this=0x1825bb0, flags=...) at kernel/qeventdispatcher_glib.cpp:434
#60 0x00007f8e9a5cbbe6 in QGuiEventDispatcherGlib::processEvents (this=<optimized out>, flags=...) at kernel/qguieventdispatcher_glib.cpp:204
#61 0x00007f8e99b3b0af in QEventLoop::processEvents (this=this@entry=0x7ffe8125ae30, flags=...) at kernel/qeventloop.cpp:149
#62 0x00007f8e99b3b3a5 in QEventLoop::exec (this=this@entry=0x7ffe8125ae30, flags=...) at kernel/qeventloop.cpp:204
#63 0x00007f8e99b40b79 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1225
#64 0x00000000004034f2 in ?? ()
#65 0x00007f8e99317ec5 in __libc_start_main (main=0x402bb0, argc=1, argv=0x7ffe8125b078, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffe8125b068) at libc-start.c:287
#66 0x0000000000403997 in _start ()

Possible duplicates by query: bug 357184, bug 344228.

Reported using DrKonqi