*** Bug 282308 has been marked as a duplicate of this bug. ***

[Comment from a bug report cleaner]
Bug 283113 (KDE SC 4.6.0) contains a crash with a similar backtrace but appearing on System Settings. 

[KCrash Handler]
#6  QVariant::userType (this=0xb1) at kernel/qvariant.cpp:1792
#7  0x00007fe20b51ff5e in qvariant_cast<QDBusArgument> (this=0xc72b30) at
/usr/include/QtCore/qvariant.h:580
#8  qVariantValue<QDBusArgument> (this=0xc72b30) at
/usr/include/QtCore/qvariant.h:599
#9  PolkitQt1::Authority::Private::init (this=0xc72b30) at
/usr/src/debug/polkit-qt-1-0.99.1/core/polkitqt1-authority.cpp:224
#10 0x00007fe20b521600 in PolkitQt1::Authority::Authority (this=0xc72380,
authority=0x0, parent=<value optimized out>) at
/usr/src/debug/polkit-qt-1-0.99.1/core/polkitqt1-authority.cpp:153
#11 0x00007fe20b5217ba in PolkitQt1::Authority::instance (authority=0x0) at
/usr/src/debug/polkit-qt-1-0.99.1/core/polkitqt1-authority.cpp:49
#12 0x00007fe20b75b090 in KAuth::Polkit1Backend::Polkit1Backend (this=0xc71f20)
at
/usr/src/debug/kdelibs-4.6.0/kdecore/auth/backends/polkit-1/Polkit1Backend.cpp:69
#13 0x00007fe20b75b17d in qt_plugin_instance () at
/usr/src/debug/kdelibs-4.6.0/kdecore/auth/backends/polkit-1/Polkit1Backend.cpp:229
#14 0x00007fe22a03d4f9 in KAuth::BackendsManager::retrieveInstancesIn
(path=<value optimized out>) at
/usr/src/debug/kdelibs-4.6.0/kdecore/auth/BackendsManager.cpp:69
#15 0x00007fe22a07af61 in KAuth::BackendsManager::init () at
/usr/src/debug/kdelibs-4.6.0/kdecore/auth/BackendsManager.cpp:81
#16 0x00007fe22a07b63d in KAuth::BackendsManager::authBackend () at
/usr/src/debug/kdelibs-4.6.0/kdecore/auth/BackendsManager.cpp:123
#17 0x00007fe22a07bb8b in KAuth::Action::setName (this=0xc6f750, name=...) at
/usr/src/debug/kdelibs-4.6.0/kdecore/auth/kauthaction.cpp:108
#18 0x00007fe22a07c5aa in KAuth::Action::Action (this=0xc6f750, name=...) at
/usr/src/debug/kdelibs-4.6.0/kdecore/auth/kauthaction.cpp:61
...

I recorded this backtrace on Spark (ARM) Tablet with Trunk:Testing Active image from 13.03.12. It looks identical to this bug.

BR

vgrade


Application: KDE Daemon (kdeinit4), signal: Segmentation fault
[Current thread is 1 (Thread 0x41b07670 (LWP 399))]

Thread 3 (Thread 0x46467420 (LWP 465)):
#0  0x40875af4 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#1  0x408436ac in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#2  0x4095ac98 in ?? () from /usr/lib/libQtCore.so.4
#3  0x4095ac98 in ?? () from /usr/lib/libQtCore.so.4
Backtrace stopped: previous frame identical to this frame (corrupt stack?)

Thread 2 (Thread 0x46dff420 (LWP 481)):
#0  0x413b2274 in __libc_enable_asynccancel () at ../nptl/cancellation.c:43
#1  0x41399660 in __poll (fds=0x46e029c0, nfds=3, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:85
#2  0x41831dcc in ?? () from /lib/libglib-2.0.so.0
#3  0x41831dcc in ?? () from /lib/libglib-2.0.so.0
Backtrace stopped: previous frame identical to this frame (corrupt stack?)

Thread 1 (Thread 0x41b07670 (LWP 399)):
[KCrash Handler]
#6  0x40865740 in QVariant::userType() const () from /usr/lib/libQtCore.so.4
#7  0x4647d1b0 in PolkitQt1::Authority::Private::init() () from /usr/lib/libpolkit-qt-core-1.so.1
#8  0x4647e48c in PolkitQt1::Authority::Authority(_PolkitAuthority*, QObject*) () from /usr/lib/libpolkit-qt-core-1.so.1
#9  0x4647e544 in PolkitQt1::Authority::instance(_PolkitAuthority*) () from /usr/lib/libpolkit-qt-core-1.so.1
#10 0x4646a4cc in KAuth::Polkit1Backend::Polkit1Backend (this=0x177b10) at ../../kdecore/auth/backends/polkit-1/Polkit1Backend.cpp:69
#11 0x4646b0ec in qt_plugin_instance () at ../../kdecore/auth/backends/polkit-1/Polkit1Backend.cpp:229
#12 0x4082aa10 in QPluginLoader::instance() () from /usr/lib/libQtCore.so.4
#13 0x405dd530 in BackendsManager::retrieveInstancesIn (path=<value optimized out>) at ../../kdecore/auth/BackendsManager.cpp:69
#14 0x405dd730 in BackendsManager::init () at ../../kdecore/auth/BackendsManager.cpp:81
#15 0x405dddc8 in BackendsManager::authBackend () at ../../kdecore/auth/BackendsManager.cpp:123
#16 0x405da090 in Action::setName (this=0xbefdc6f0, name=...) at ../../kdecore/auth/kauthaction.cpp:108
#17 0x405da1f8 in Action::Action (this=0xbefdc6f0, name=...) at ../../kdecore/auth/kauthaction.cpp:61
#18 0x430720b8 in PowerDevilUPowerBackend::brightness(enum PowerDevil::BackendInterface::BrightnessControlType) const (this=0x18ff88, type=<value optimized out>) at ../../../powerdevil/daemon/backends/upower/powerdevilupowerbackend.cpp:195
#19 0x43074688 in PowerDevilUPowerBackend::init (this=0x18ff88) at ../../../powerdevil/daemon/backends/upower/powerdevilupowerbackend.cpp:110
#20 0x4309ecc0 in Core::loadCore (this=<value optimized out>, backend=<value optimized out>) at ../../../powerdevil/daemon/powerdevilcore.cpp:84
#21 0x4306dee4 in KDEDPowerDevil::init (this=0x17e8f8) at ../../../powerdevil/daemon/kdedpowerdevil.cpp:89
#22 0x40855430 in QMetaCallEvent::placeMetaCall(QObject*) () from /usr/lib/libQtCore.so.4
#23 0x40855430 in QMetaCallEvent::placeMetaCall(QObject*) () from /usr/lib/libQtCore.so.4
Backtrace stopped: previous frame identical to this frame (corrupt stack?)

*** Bug 283113 has been marked as a duplicate of this bug. ***

This particular crash should have been fixed in eeef90fc5196c5056c8c4ada7b1b5d74db1e5c94. 
The CK (and systemd-logind, lately) support is not perfect, I think. There will be some polishing in the future.
But as I write in every report: if it's still happening, please open the bug once again and I'll look into it. Thank you!