Bug 332975

Summary: System settings crashed randomly, either after opening it or an item of it.
Product: [Applications] systemsettings Reporter: vcc <vcc_02>
Component: generalAssignee: Unassigned bugs mailing-list <unassigned-bugs>
Status: RESOLVED WORKSFORME    
Severity: grave    
Priority: NOR    
Version: unspecified   
Target Milestone: ---   
Platform: Kubuntu   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:

Description vcc 2014-04-02 17:42:27 UTC 
Almost every application crashes at some point in Kubuntu 14.04 beta2. This crash of system settings is one, which provided enough debug information to make drkonqi say the report is probably useful. Drkonqi crashes many times and this was one of the times it didn't and it allowed me to save the report. However, I couldn't log in to use drkonqi to report, because it said something about "kded is not running". (I'm using a browser now to fill in the forms, from ZorinOS 4). BTW, Firefox also crashes and drkonqi crashes can't install debug packages.
Here is the crash report about systemsettings:

Application: System Settings (systemsettings), signal: Segmentation fault
Using host libthread_db library "/lib/i386-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0xb1539980 (LWP 5994))]

Thread 3 (Thread 0xadc29b40 (LWP 5995)):
#0  0xb29c812e in __pthread_mutex_unlock_usercnt (mutex=0xad300558, decr=1) at pthread_mutex_unlock.c:57
#1  0xb5de1b34 in pthread_mutex_unlock (mutex=0xad300558) at forward.c:194
#2  0xb2923140 in g_mutex_unlock () from /lib/i386-linux-gnu/libglib-2.0.so.0
#3  0xb28de532 in g_main_context_iteration () from /lib/i386-linux-gnu/libglib-2.0.so.0
#4  0xb612895f in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#5  0xb60f7823 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#6  0xb60f7b49 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#7  0xb5fe423d in QThread::exec() () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#8  0xb60d7c44 in ?? () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#9  0xb5fe6b6f in ?? () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#10 0xb29c4f70 in start_thread (arg=0xadc29b40) at pthread_create.c:312
#11 0xb5dd470e in clone () at ../sysdeps/unix/sysv/linux/i386/clone.S:129

Thread 2 (Thread 0xad21fb40 (LWP 5996)):
#0  0xb77a2424 in __kernel_vsyscall ()
#1  0xb29c8d4b in pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/i386/i686/../i486/pthread_cond_wait.S:187
#2  0xb5de18ec in __pthread_cond_wait (cond=0xb3bc18d0, mutex=0xb3bc18b8) at forward.c:149
#3  0xb3abec92 in ?? () from /usr/lib/i386-linux-gnu/libQtScript.so.4
#4  0xb3abecdf in ?? () from /usr/lib/i386-linux-gnu/libQtScript.so.4
#5  0xb29c4f70 in start_thread (arg=0xad21fb40) at pthread_create.c:312
#6  0xb5dd470e in clone () at ../sysdeps/unix/sysv/linux/i386/clone.S:129

Thread 1 (Thread 0xb1539980 (LWP 5994)):
[KCrash Handler]
#6  0xb6112c0c in QObject::~QObject() () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#7  0xb67284b5 in QWidget::~QWidget() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#8  0xb6b31c9f in QFrame::~QFrame() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#9  0xb6b356eb in QLabel::~QLabel() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#10 0xb6b3573c in QLabel::~QLabel() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#11 0xb6110bda in QObjectPrivate::deleteChildren() () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#12 0xb67283fc in QWidget::~QWidget() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#13 0xb6b31c9f in QFrame::~QFrame() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#14 0xac8cfc6c in ?? () from /usr/lib/kde4/kcm_colors.so
#15 0xb6110bda in QObjectPrivate::deleteChildren() () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#16 0xb67283fc in QWidget::~QWidget() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#17 0xb6b3288f in QGroupBox::~QGroupBox() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#18 0xb6b328cc in QGroupBox::~QGroupBox() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#19 0xb6110bda in QObjectPrivate::deleteChildren() () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#20 0xb67283fc in QWidget::~QWidget() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#21 0xb672876c in QWidget::~QWidget() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#22 0xb6110bda in QObjectPrivate::deleteChildren() () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#23 0xb67283fc in QWidget::~QWidget() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#24 0xb6b31c9f in QFrame::~QFrame() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#25 0xb6b9530f in QStackedWidget::~QStackedWidget() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#26 0xb6b9534c in QStackedWidget::~QStackedWidget() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#27 0xb6110bda in QObjectPrivate::deleteChildren() () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#28 0xb67283fc in QWidget::~QWidget() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#29 0xb6ba1cdf in QTabWidget::~QTabWidget() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#30 0xb6ba1d1c in QTabWidget::~QTabWidget() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#31 0xb6110bda in QObjectPrivate::deleteChildren() () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#32 0xb67283fc in QWidget::~QWidget() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#33 0xb72c15ec in KCModule::~KCModule() () from /usr/lib/libkdeui.so.5
#34 0xac8ba34f in ?? () from /usr/lib/kde4/kcm_colors.so
#35 0xac8ba3ac in ?? () from /usr/lib/kde4/kcm_colors.so
#36 0xb748d5d6 in KCModuleProxy::deleteClient() () from /usr/lib/libkcmutils.so.4
#37 0xb748d685 in KCModuleProxy::~KCModuleProxy() () from /usr/lib/libkcmutils.so.4
#38 0xb748d7dc in KCModuleProxy::~KCModuleProxy() () from /usr/lib/libkcmutils.so.4
#39 0xb6110bda in QObjectPrivate::deleteChildren() () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#40 0xb67283fc in QWidget::~QWidget() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#41 0xb672876c in QWidget::~QWidget() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#42 0xb6110bda in QObjectPrivate::deleteChildren() () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#43 0xb67283fc in QWidget::~QWidget() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#44 0xb6b31c9f in QFrame::~QFrame() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#45 0xb6bbe8ff in QAbstractScrollArea::~QAbstractScrollArea() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#46 0xb6bc33ff in QScrollArea::~QScrollArea() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#47 0xb6bc343c in QScrollArea::~QScrollArea() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#48 0xb72599aa in KPageWidgetItem::~KPageWidgetItem() () from /usr/lib/libkdeui.so.5
#49 0xb7259a4c in KPageWidgetItem::~KPageWidgetItem() () from /usr/lib/libkdeui.so.5
#50 0xb7259f44 in ?? () from /usr/lib/libkdeui.so.5
#51 0xb725a7d9 in KPageWidgetModel::removePage(KPageWidgetItem*) () from /usr/lib/libkdeui.so.5
#52 0xb7259647 in KPageWidget::removePage(KPageWidgetItem*) () from /usr/lib/libkdeui.so.5
#53 0xb746ca12 in ModuleView::closeModules() () from /usr/lib/libsystemsettingsview.so.2
#54 0xae7f2af9 in ?? () from /usr/lib/kde4/icon_mode.so
#55 0xb610e0f7 in QMetaObject::activate(QObject*, QMetaObject const*, int, void**) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#56 0xb66cb72d in QAction::triggered(bool) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#57 0xb66cd324 in QAction::activate(QAction::ActionEvent) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#58 0xb6bbc870 in QToolButton::nextCheckState() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#59 0xb6aeadf3 in ?? () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#60 0xb6aeaf3e in QAbstractButton::mouseReleaseEvent(QMouseEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#61 0xb6bbc7e7 in QToolButton::mouseReleaseEvent(QMouseEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#62 0xb672c3fa in QWidget::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#63 0xb6aebf42 in QAbstractButton::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#64 0xb6bbc8d4 in QToolButton::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#65 0xb66d27f4 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#66 0xb66daea0 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#67 0xb72220a4 in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#68 0xb60f8e4a in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#69 0xb66d8b53 in QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#70 0xb675c778 in ?? () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#71 0xb675bec5 in QApplication::x11ProcessEvent(_XEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#72 0xb6787524 in ?? () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#73 0xb28de1e3 in g_main_context_dispatch () from /lib/i386-linux-gnu/libglib-2.0.so.0
#74 0xb28de468 in ?? () from /lib/i386-linux-gnu/libglib-2.0.so.0
#75 0xb28de528 in g_main_context_iteration () from /lib/i386-linux-gnu/libglib-2.0.so.0
#76 0xb612895f in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#77 0xb67875de in ?? () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#78 0xb60f7823 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#79 0xb60f7b49 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#80 0xb60fd8fe in QCoreApplication::exec() () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#81 0xb66d0a24 in QApplication::exec() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#82 0x08050490 in ?? ()
#83 0xb5d01a83 in __libc_start_main (main=0x80500b0, argc=5, argv=0xbfbc7b54, init=0x8056f90 <__libc_csu_init>, fini=0x8057000 <__libc_csu_fini>, rtld_fini=0xb77b2180 <_dl_fini>, stack_end=0xbfbc7b4c) at libc-start.c:287
#84 0x080504d1 in _start ()

Reproducible: Sometimes

Steps to Reproduce:
1. Open system settings and wait a second, or enter a setting. 90% of these actions will trigger a crash.
2.
3.



These kinds of bugs like this one appear at least since Kubuntu 13.04. What's different in 14.04 is that the taskbar and the desktop reappear (not always). It may be related to my computer config: 
i5, 32-bit Kubuntu (although the CPU is 64-bit), 4GB RAM, Nvidia GeForce 9800 GT.
On computers with Intel graphics, there is no crash.
Most likely these bug reports have nothing to do with the applications which crash, but may show something else. I'm not an advanced user to do more, but if possible, please forward the report upstream if that's the case. I can't even install debug packages. The installer crashes every time. Using apt-get, something either hangs or reports an invalid package or an invalid download link, but nothing installs.

If it is of any help, regarding the same behavior, here is a similar crash report from Kate:

Application: Kate (kate), signal: Segmentation fault
Using host libthread_db library "/lib/i386-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0xb4dcb740 (LWP 6076))]

Thread 4 (Thread 0xb188eb40 (LWP 6077)):
#0  0xb7797424 in __kernel_vsyscall ()
#1  0xb5f35d4b in pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/i386/i686/../i486/pthread_cond_wait.S:187
#2  0xb76be8ec in __pthread_cond_wait (cond=0xb1d7e8d0, mutex=0xb1d7e8b8) at forward.c:149
#3  0xb1c7bc92 in ?? () from /usr/lib/i386-linux-gnu/libQtScript.so.4
#4  0xb1c7bcdf in ?? () from /usr/lib/i386-linux-gnu/libQtScript.so.4
#5  0xb5f31f70 in start_thread (arg=0xb188eb40) at pthread_create.c:312
#6  0xb76b170e in clone () at ../sysdeps/unix/sysv/linux/i386/clone.S:129

Thread 3 (Thread 0xaf7b4b40 (LWP 6078)):
#0  0xb76beac8 in pthread_mutex_lock (mutex=0xaee00558) at forward.c:192
#1  0xb5e90100 in g_mutex_lock () from /lib/i386-linux-gnu/libglib-2.0.so.0
#2  0xb5e4ae0b in g_main_context_check () from /lib/i386-linux-gnu/libglib-2.0.so.0
#3  0xb5e4b37a in ?? () from /lib/i386-linux-gnu/libglib-2.0.so.0
#4  0xb5e4b528 in g_main_context_iteration () from /lib/i386-linux-gnu/libglib-2.0.so.0
#5  0xb621395f in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#6  0xb61e2823 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#7  0xb61e2b49 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#8  0xb60cf23d in QThread::exec() () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#9  0xb61c2c44 in ?? () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#10 0xb60d1b6f in ?? () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#11 0xb5f31f70 in start_thread (arg=0xaf7b4b40) at pthread_create.c:312
#12 0xb76b170e in clone () at ../sysdeps/unix/sysv/linux/i386/clone.S:129

Thread 2 (Thread 0xaedffb40 (LWP 6173)):
#0  0xb5f3513a in __pthread_mutex_unlock_usercnt (mutex=0xae400558, decr=<optimized out>) at pthread_mutex_unlock.c:93
#1  0xb76beb34 in pthread_mutex_unlock (mutex=0xae400558) at forward.c:194
#2  0xb5e90140 in g_mutex_unlock () from /lib/i386-linux-gnu/libglib-2.0.so.0
#3  0xb5e4b2cf in ?? () from /lib/i386-linux-gnu/libglib-2.0.so.0
#4  0xb5e4b528 in g_main_context_iteration () from /lib/i386-linux-gnu/libglib-2.0.so.0
#5  0xb621395f in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#6  0xb61e2823 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#7  0xb61e2b49 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#8  0xb60cf23d in QThread::exec() () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#9  0xb61c2c44 in ?? () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#10 0xb60d1b6f in ?? () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#11 0xb5f31f70 in start_thread (arg=0xaedffb40) at pthread_create.c:312
#12 0xb76b170e in clone () at ../sysdeps/unix/sysv/linux/i386/clone.S:129

Thread 1 (Thread 0xb4dcb740 (LWP 6076)):
[KCrash Handler]
#6  0xb61e3f55 in QCoreApplicationPrivate::sendThroughObjectEventFilters(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#7  0xb6c497d1 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#8  0xb6c502d3 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#9  0xb65a60a4 in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#10 0xb61e3e4a in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#11 0xb6ca35fd in QWidget::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#12 0xb70a978c in QFrame::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#13 0xb7137d0f in QAbstractScrollArea::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#14 0xb71dca4c in QAbstractItemView::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#15 0xb71ebf9c in QHeaderView::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#16 0xb6c497f4 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#17 0xb6c502d3 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#18 0xb65a60a4 in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#19 0xb61e3e4a in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#20 0xb6ca35fd in QWidget::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#21 0xb70a978c in QFrame::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#22 0xb7137d0f in QAbstractScrollArea::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#23 0xb71dca4c in QAbstractItemView::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#24 0xb7257930 in QTreeWidget::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#25 0xb6c497f4 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#26 0xb6c502d3 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#27 0xb65a60a4 in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#28 0xb61e3e4a in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#29 0xb6ca35fd in QWidget::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#30 0xb70aaee7 in QGroupBox::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#31 0xb6c497f4 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#32 0xb6c502d3 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#33 0xb65a60a4 in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#34 0xb61e3e4a in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#35 0xb6ca35fd in QWidget::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#36 0xb6c497f4 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#37 0xb6c502d3 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#38 0xb65a60a4 in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#39 0xb61e3e4a in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#40 0xb6ca35fd in QWidget::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#41 0xb6c497f4 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#42 0xb6c502d3 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#43 0xb65a60a4 in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#44 0xb61e3e4a in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#45 0xb6c4b9f6 in QApplicationPrivate::enterModal(QWidget*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#46 0xb6ca041e in QWidgetPrivate::show_helper() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#47 0xb6ca22bd in QWidget::setVisible(bool) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#48 0xb717a487 in QDialog::setVisible(bool) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#49 0xb7179e9b in QDialog::exec() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#50 0xb579e671 in KEncodingFileDialog::getSaveUrlAndEncoding(QString const&, QString const&, QString const&, QWidget*, QString const&) () from /usr/lib/libkio.so.5
#51 0xb1e8fc43 in KateDocument::documentSaveAs() () from /usr/lib/libkatepartinterfaces.so.4
#52 0xb1e8a5e8 in KateDocument::documentSave() () from /usr/lib/libkatepartinterfaces.so.4
#53 0xb1ea996b in ?? () from /usr/lib/libkatepartinterfaces.so.4
#54 0xb61f90f7 in QMetaObject::activate(QObject*, QMetaObject const*, int, void**) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#55 0xb6c4272d in QAction::triggered(bool) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#56 0xb6c44324 in QAction::activate(QAction::ActionEvent) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#57 0xb7133870 in QToolButton::nextCheckState() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#58 0xb7061df3 in ?? () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#59 0xb7061f3e in QAbstractButton::mouseReleaseEvent(QMouseEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#60 0xb71337e7 in QToolButton::mouseReleaseEvent(QMouseEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#61 0xb6ca33fa in QWidget::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#62 0xb7062f42 in QAbstractButton::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#63 0xb71338d4 in QToolButton::event(QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#64 0xb6c497f4 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#65 0xb6c51ea0 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#66 0xb65a60a4 in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#67 0xb61e3e4a in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#68 0xb6c4fb53 in QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#69 0xb6cd3778 in ?? () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#70 0xb6cd2ec5 in QApplication::x11ProcessEvent(_XEvent*) () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#71 0xb6cfe524 in ?? () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#72 0xb5e4b1e3 in g_main_context_dispatch () from /lib/i386-linux-gnu/libglib-2.0.so.0
#73 0xb5e4b468 in ?? () from /lib/i386-linux-gnu/libglib-2.0.so.0
#74 0xb5e4b528 in g_main_context_iteration () from /lib/i386-linux-gnu/libglib-2.0.so.0
#75 0xb621395f in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#76 0xb6cfe5de in ?? () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#77 0xb61e2823 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#78 0xb61e2b49 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#79 0xb61e88fe in QCoreApplication::exec() () from /usr/lib/i386-linux-gnu/libQtCore.so.4
#80 0xb6c47a24 in QApplication::exec() () from /usr/lib/i386-linux-gnu/libQtGui.so.4
#81 0xb779092d in kdemain () from /usr/lib/kde4/libkdeinit/libkdeinit4_kate.so
#82 0x0804854b in ?? ()
#83 0xb75dea83 in __libc_start_main (main=0x8048530, argc=2, argv=0xbff67c24, init=0x8048650 <__libc_csu_init>, fini=0x80486c0 <__libc_csu_fini>, rtld_fini=0xb77a7180 <_dl_fini>, stack_end=0xbff67c1c) at libc-start.c:287
#84 0x0804856e in _start ()
Comment 1 Jekyll Wu 2014-04-07 07:45:42 UTC 
Your Qt installation might be broken according to the backtrace
Comment 2 vcc 2014-04-07 15:47:13 UTC 
Thank you for analysis. If I manage to get to terminal (at least Alt-F1) and I type:
sudo apt-get update, I get some errors for the last 2-3 items. Something like:

E: Error: Opening the cache (Encountered a section with no package: header, E:Problem with MergeList /var/lib/apt/lists/ro.archive.ubuntu.com_dists_trusty_main_i18n_Translation-en, E:The package lists or status file could not be parsed or opened.)run-parts: /etc/update-motd.d/90-updates-available exited with return code 255

I remember this problem was present even in 13.10. Perhaps I have to wait for the final release.
Comment 3 Christoph Feck 2014-04-18 20:17:09 UTC 
Is this issue still unresolved?
Comment 4 vcc 2014-04-19 10:16:53 UTC 
I was thinking to wait a few more day, but it wasn't needed. Running sudo apt-get update returned no error, so I assume there are no broken packages in the final version.
SystemSettings can be accessed witouht any crash. Other applications like Firefox, Dolphin or Kate do not crash. Nor the desktop.
I am surprised to find out that krita is not installed by default, so this was a good way to test an installation. It installed and can be run without a crash.
So far, I think the problems are gone. Thanks to all who worked on this.
Comment 5 Christoph Feck 2014-04-27 12:37:35 UTC 
Thanks for the update, closing.