Application: systemsettings5 (5.2.2)
 (Compiled from sources)
Qt Version: 5.4.1
Operating System: Linux 3.19.0-16-generic x86_64
Distribution: Ubuntu 15.04

-- Information about the crash:
Estava instalando ícones manuelmente, jogando os na pasta /usr/share/icons, e o plasma simplesmente desapareceu, e apareceu esse erro ao rodar o systemsettings5 (Configurações do Sistema) pelo terminal. Não foi possível inicializar o plasma novamente, assim sendo necessário a reinstalação do sistema Kubuntu 15.4 com KDE Plasma 5.

The crash can be reproduced every time.

-- Backtrace:
Application: Configurações do Sistema (systemsettings5), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7ff689f2a780 (LWP 4141))]

Thread 5 (Thread 0x7ff679537700 (LWP 4142)):
#0  0x00007ff6866438dd in poll () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007ff684939b72 in ?? () from /usr/lib/x86_64-linux-gnu/libxcb.so.1
#2  0x00007ff68493b64f in xcb_wait_for_event () from /usr/lib/x86_64-linux-gnu/libxcb.so.1
#3  0x00007ff67babb099 in ?? () from /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqxcb.so
#4  0x00007ff686ccbb0e in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007ff6838376aa in start_thread (arg=0x7ff679537700) at pthread_create.c:333
#6  0x00007ff68664eeed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 4 (Thread 0x7ff66a007700 (LWP 4143)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007ff66d05d4fb in ?? () from /usr/lib/x86_64-linux-gnu/dri/r600_dri.so
#2  0x00007ff66d05cc87 in ?? () from /usr/lib/x86_64-linux-gnu/dri/r600_dri.so
#3  0x00007ff6838376aa in start_thread (arg=0x7ff66a007700) at pthread_create.c:333
#4  0x00007ff68664eeed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 3 (Thread 0x7ff6537f6700 (LWP 4393)):
#0  0x00007ff6866438dd in poll () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007ff683311ebc in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007ff683311fcc in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007ff686f62c6c in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007ff686f073e2 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007ff686cc6b44 in QThread::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007ff685c79f65 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#7  0x00007ff686ccbb0e in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007ff6838376aa in start_thread (arg=0x7ff6537f6700) at pthread_create.c:333
#9  0x00007ff68664eeed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 2 (Thread 0x7ff65def7700 (LWP 4394)):
#0  0x00007ff683356789 in g_mutex_lock () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#1  0x00007ff683311fb8 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007ff686f62c6c in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007ff686f073e2 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007ff686cc6b44 in QThread::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007ff685c79f65 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#6  0x00007ff686ccbb0e in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007ff6838376aa in start_thread (arg=0x7ff65def7700) at pthread_create.c:333
#8  0x00007ff68664eeed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 1 (Thread 0x7ff689f2a780 (LWP 4141)):
[KCrash Handler]
#6  0x0000000000000030 in ?? ()
#7  0x00007ff655f4b6e1 in KDecoration2::Decoration::update(QRect const&) () from /usr/lib/x86_64-linux-gnu/libkdecorations2.so.5
#8  0x00007ff655f4b75b in KDecoration2::Decoration::update() () from /usr/lib/x86_64-linux-gnu/libkdecorations2.so.5
#9  0x00007ff6558d6370 in ?? () from /usr/lib/x86_64-linux-gnu/qt5/plugins/org.kde.kdecoration2/breezedecoration.so
#10 0x00007ff6558f67a8 in ?? () from /usr/lib/x86_64-linux-gnu/qt5/plugins/org.kde.kdecoration2/breezedecoration.so
#11 0x00007ff686cac5ca in QPropertyAnimation::updateCurrentValue(QVariant const&) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#12 0x00007ff686ca7f48 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#13 0x00007ff686ca8d1b in QVariantAnimation::updateCurrentTime(int) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#14 0x00007ff686ca4baf in QAbstractAnimation::setCurrentTime(int) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#15 0x00007ff686ca4e96 in QUnifiedTimer::updateAnimationTimers(long long) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#16 0x00007ff685cb4a5e in QAbstractAnimationJob::setState(QAbstractAnimationJob::State) () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#17 0x00007ff6857cedac in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#18 0x00007ff685829244 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#19 0x00007ff6857d7ea3 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#20 0x00007ff685735dd3 in QQuickItem::geometryChanged(QRectF const&, QRectF const&) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#21 0x00007ff68573a1ae in QQuickItem::setWidth(double) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#22 0x00007ff685746be6 in QQuickItem::qt_metacall(QMetaObject::Call, int, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#23 0x00007ff685bf3ba7 in QQmlPropertyPrivate::writeBinding(QObject*, QQmlPropertyData const&, QQmlContextData*, QQmlJavaScriptExpression*, QV4::ValueRef, bool, QFlags<QQmlPropertyPrivate::WriteFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#24 0x00007ff685c6851c in QQmlBinding::update(QFlags<QQmlPropertyPrivate::WriteFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#25 0x00007ff685c68c7e in QQmlBinding::expressionChanged(QQmlJavaScriptExpression*) () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#26 0x00007ff685c42497 in QQmlNotifier::emitNotify(QQmlNotifierEndpoint*, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#27 0x00007ff685c4245e in QQmlNotifier::emitNotify(QQmlNotifierEndpoint*, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#28 0x00007ff685bdf10c in QQmlData::signalEmitted(QAbstractDeclarativeData*, QObject*, int, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#29 0x00007ff686f3a141 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#30 0x00007ff685735e39 in QQuickItem::geometryChanged(QRectF const&, QRectF const&) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#31 0x00007ff6857cdedc in QQuickFlickable::geometryChanged(QRectF const&, QRectF const&) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#32 0x00007ff68573ac60 in QQuickItem::setSize(QSizeF const&) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#33 0x00007ff685730a8a in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#34 0x00007ff6857329a2 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#35 0x00007ff685735dd3 in QQuickItem::geometryChanged(QRectF const&, QRectF const&) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#36 0x00007ff68573ac60 in QQuickItem::setSize(QSizeF const&) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#37 0x00007ff685730a8a in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#38 0x00007ff6857329a2 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#39 0x00007ff685735dd3 in QQuickItem::geometryChanged(QRectF const&, QRectF const&) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#40 0x00007ff68573ac60 in QQuickItem::setSize(QSizeF const&) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#41 0x00007ff685730a8a in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#42 0x00007ff6857329a2 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#43 0x00007ff685735dd3 in QQuickItem::geometryChanged(QRectF const&, QRectF const&) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#44 0x00007ff68573ac60 in QQuickItem::setSize(QSizeF const&) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#45 0x00007ff685730a8a in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#46 0x00007ff6857329a2 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#47 0x00007ff685735dd3 in QQuickItem::geometryChanged(QRectF const&, QRectF const&) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#48 0x00007ff68573ac60 in QQuickItem::setSize(QSizeF const&) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#49 0x00007ff685730a8a in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#50 0x00007ff6857329a2 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#51 0x00007ff685735dd3 in QQuickItem::geometryChanged(QRectF const&, QRectF const&) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#52 0x00007ff68573ac60 in QQuickItem::setSize(QSizeF const&) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#53 0x00007ff666ce6798 in ?? () from /usr/lib/x86_64-linux-gnu/qt5/qml/QtQuick/Layouts/libqquicklayoutsplugin.so
#54 0x00007ff687a20186 in QGridLayoutEngine::setGeometries(QRectF const&, QAbstractLayoutStyleInfo const*) () from /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5
#55 0x00007ff666ce5f0f in ?? () from /usr/lib/x86_64-linux-gnu/qt5/qml/QtQuick/Layouts/libqquicklayoutsplugin.so
#56 0x00007ff666ce64c7 in ?? () from /usr/lib/x86_64-linux-gnu/qt5/qml/QtQuick/Layouts/libqquicklayoutsplugin.so
#57 0x00007ff68573ac60 in QQuickItem::setSize(QSizeF const&) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#58 0x00007ff685730a8a in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#59 0x00007ff6857329a2 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#60 0x00007ff685735dd3 in QQuickItem::geometryChanged(QRectF const&, QRectF const&) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#61 0x00007ff68573a4fe in QQuickItem::setHeight(double) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#62 0x00007ff685800d8f in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#63 0x00007ff685802442 in QQuickView::resizeEvent(QResizeEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#64 0x00007ff68774c7b5 in QWindow::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5
#65 0x00007ff685759dd3 in QQuickWindow::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#66 0x00007ff687d03b2c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#67 0x00007ff687d09000 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#68 0x00007ff686f09c2b in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#69 0x00007ff687744f41 in QGuiApplicationPrivate::processExposeEvent(QWindowSystemInterfacePrivate::ExposeEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5
#70 0x00007ff687745bbd in QGuiApplicationPrivate::processWindowSystemEvent(QWindowSystemInterfacePrivate::WindowSystemEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5
#71 0x00007ff68772a34f in QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5
#72 0x00007ff67bae5590 in ?? () from /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqxcb.so
#73 0x00007ff683311c3d in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#74 0x00007ff683311f20 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#75 0x00007ff683311fcc in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#76 0x00007ff686f62c57 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#77 0x00007ff686f073e2 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#78 0x00007ff686f0f02c in QCoreApplication::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#79 0x000000000040eebc in main ()

Reported using DrKonqi