This is with Qt from the 5.6 branch (not 5.6.0, the 5.6 branch) from git (e69e69519661954716d59bfa5bbd0626515cfda9, about three days old), a recent kded (e0781c3963fc2d3569f442d10e2a2d07a4dd9724), and powerdevil from dc76062a0616d1b64b516e4132cf9613d306770d (February): #0 pthread_cond_wait () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185 #1 0x00007ffff5b97e93 in wait (time=18446744073709551615, this=0x555555bc7240) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/thread/qwaitcondition_unix.cpp:136 #2 QWaitCondition::wait (this=this@entry=0x555555bbb180, mutex=mutex@entry=0x555555bbb178, time=time@entry=18446744073709551615) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/thread/qwaitcondition_unix.cpp:208 #3 0x00007ffff7f9b57b in QDBusPendingCallPrivate::waitForFinished (this=this@entry=0x555555bbb140) at /var/tmp/portage/dev-qt/qtdbus-5.6.9999/work/qtdbus-5.6.9999/src/dbus/qdbuspendingcall.cpp:234 #4 0x00007ffff7f550f9 in QDBusConnectionPrivate::sendWithReply (this=0x7fffdc011080, message=..., sendMode=1, timeout=-1) at /var/tmp/portage/dev-qt/qtdbus-5.6.9999/work/qtdbus-5.6.9999/src/dbus/qdbusintegrator.cpp:1955 #5 0x00007ffff7f4002b in QDBusConnection::call (this=this@entry=0x7fffdc014450, message=..., mode=mode@entry=QDBus::Block, timeout=<optimized out>) at /var/tmp/portage/dev-qt/qtdbus-5.6.9999/work/qtdbus-5.6.9999/src/dbus/qdbusconnection.cpp:682 #6 0x00007ffff7f61a2b in QDBusAbstractInterface::callWithArgumentList (this=0x7fffdc014370, mode=QDBus::Block, mode@entry=QDBus::AutoDetect, method=..., args=...) at /var/tmp/portage/dev-qt/qtdbus-5.6.9999/work/qtdbus-5.6.9999/src/dbus/qdbusabstractinterface.cpp:488 #7 0x00007ffff7f6242f in QDBusAbstractInterface::internalConstCall (this=<optimized out>, mode=mode@entry=QDBus::AutoDetect, method=..., args=...) at /var/tmp/portage/dev-qt/qtdbus-5.6.9999/work/qtdbus-5.6.9999/src/dbus/qdbusabstractinterface.cpp:843 #8 0x00007ffff7f46108 in QDBusConnectionInterface::isServiceRegistered (this=<optimized out>, serviceName=...) at /var/tmp/portage/dev-qt/qtdbus-5.6.9999/work/qtdbus-5.6.9999/src/dbus/qdbusconnectioninterface.cpp:202 #9 0x00007fffd01831c0 in KDEDPowerDevil::init (this=0x555555cbf300) at /var/tmp/portage/kde-plasma/powerdevil-9999/work/powerdevil-9999/daemon/kdedpowerdevil.cpp:70 #10 0x00007ffff5da7b3a in QObject::event (this=0x555555cbf300, e=<optimized out>) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qobject.cpp:1256 #11 0x00007ffff725fe54 in QApplicationPrivate::notify_helper (this=<optimized out>, receiver=0x555555cbf300, e=0x555555c8cda0) at /var/tmp/portage/dev-qt/qtwidgets-5.6.9999/work/qtwidgets-5.6.9999/src/widgets/kernel/qapplication.cpp:3771 #12 0x00007ffff7264c9e in QApplication::notify (this=0x7fffffffd750, receiver=0x555555cbf300, e=0x555555c8cda0) at /var/tmp/portage/dev-qt/qtwidgets-5.6.9999/work/qtwidgets-5.6.9999/src/widgets/kernel/qapplication.cpp:3528 #13 0x00007ffff5d766d8 in QCoreApplication::notifyInternal2 (receiver=0x555555cbf300, event=event@entry=0x555555c8cda0) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.cpp:1016 #14 0x00007ffff5d79287 in sendEvent (event=0x555555c8cda0, receiver=<optimized out>) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.h:227 #15 QCoreApplicationPrivate::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0, data=0x555555756db0) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.cpp:1651 #16 0x00007ffff5d7989e in QCoreApplication::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.cpp:1509 #17 0x00007ffff5dd1139 in postEventSourceDispatch (s=0x555555784af0) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qeventdispatcher_glib.cpp:270 #18 0x00007ffff2d0f08c in g_main_dispatch (context=0x7fffe4002450) at /var/tmp/portage/dev-libs/glib-2.44.1-r1/work/glib-2.44.1/glib/gmain.c:3122 #19 g_main_context_dispatch (context=context@entry=0x7fffe4002450) at /var/tmp/portage/dev-libs/glib-2.44.1-r1/work/glib-2.44.1/glib/gmain.c:3737 #20 0x00007ffff2d0f398 in g_main_context_iterate (context=context@entry=0x7fffe4002450, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.44.1-r1/work/glib-2.44.1/glib/gmain.c:3808 #21 0x00007ffff2d0f4a1 in g_main_context_iteration (context=0x7fffe4002450, may_block=1) at /var/tmp/portage/dev-libs/glib-2.44.1-r1/work/glib-2.44.1/glib/gmain.c:3869 #22 0x00007ffff5dd11ed in QEventDispatcherGlib::processEvents (this=0x555555799020, flags=...) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qeventdispatcher_glib.cpp:417 #23 0x00007ffff5d74b5a in QEventLoop::exec (this=this@entry=0x7fffffffd620, flags=..., flags@entry=...) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qeventloop.cpp:204 #24 0x00007ffff5d7db96 in QCoreApplication::exec () at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.cpp:1286 #25 0x00007ffff65ceeda in QGuiApplication::exec () at /var/tmp/portage/dev-qt/qtgui-5.6.9999/work/qtgui-5.6.9999/src/gui/kernel/qguiapplication.cpp:1601 #26 0x00007ffff725c30b in QApplication::exec () at /var/tmp/portage/dev-qt/qtwidgets-5.6.9999/work/qtwidgets-5.6.9999/src/widgets/kernel/qapplication.cpp:2974 #27 0x00007ffff7bd11e7 in kdemain (argc=1, argv=<optimized out>) at /var/tmp/portage/kde-frameworks/kded-9999/work/kded-9999/src/kded.cpp:767 #28 0x00007ffff783a9e4 in __libc_start_main (main=0x5555555548b0 <main(int, char**)>, argc=1, argv=0x7fffffffd918, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffffffd908) at libc-start.c:297 #29 0x0000555555554919 in _start () plasmashell won't even show its panels of course.
...while the other thread is stuck on this: Thread 3 (Thread 0x7fffe21bf700 (LWP 44964)): #0 pthread_cond_wait () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185 #1 0x00007ffff5b97e93 in wait (time=18446744073709551615, this=0x7fffdc014870) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/thread/qwaitcondition_unix.cpp:136 #2 QWaitCondition::wait (this=this@entry=0x7fffdc010138, mutex=mutex@entry=0x7fffdc010130, time=time@entry=18446744073709551615) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/thread/qwaitcondition_unix.cpp:208 #3 0x00007ffff5b90343 in QSemaphore::acquire (this=this@entry=0x7fffe21be8f0, n=n@entry=1) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/thread/qsemaphore.cpp:137 #4 0x00007ffff7f52c8f in QDBusConnectionPrivate::handleObjectCall (this=0x7fffdc0030f0, msg=...) at /var/tmp/portage/dev-qt/qtdbus-5.6.9999/work/qtdbus-5.6.9999/src/dbus/qdbusintegrator.cpp:1506 #5 0x00007ffff5da7b3a in QObject::event (this=0x7fffdc0030f0, e=<optimized out>) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qobject.cpp:1256 #6 0x00007ffff5d764f5 in doNotify (receiver=<optimized out>, event=<optimized out>) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.cpp:1091 #7 0x00007ffff5d76678 in notify (event=<optimized out>, receiver=<optimized out>, this=<optimized out>) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.cpp:1077 #8 QCoreApplication::notifyInternal2 (receiver=0x7fffdc0030f0, event=event@entry=0x555555b5a280) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.cpp:1016 #9 0x00007ffff5d79287 in sendEvent (event=0x555555b5a280, receiver=<optimized out>) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.h:227 #10 QCoreApplicationPrivate::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0, data=0x55555579e180) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.cpp:1651 #11 0x00007ffff5d7989e in QCoreApplication::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.cpp:1509 #12 0x00007ffff5dd1139 in postEventSourceDispatch (s=0x7fffdc0012d0) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qeventdispatcher_glib.cpp:270 #13 0x00007ffff2d0f08c in g_main_dispatch (context=0x7fffdc000990) at /var/tmp/portage/dev-libs/glib-2.44.1-r1/work/glib-2.44.1/glib/gmain.c:3122 #14 g_main_context_dispatch (context=context@entry=0x7fffdc000990) at /var/tmp/portage/dev-libs/glib-2.44.1-r1/work/glib-2.44.1/glib/gmain.c:3737 #15 0x00007ffff2d0f398 in g_main_context_iterate (context=context@entry=0x7fffdc000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.44.1-r1/work/glib-2.44.1/glib/gmain.c:3808 #16 0x00007ffff2d0f4a1 in g_main_context_iteration (context=0x7fffdc000990, may_block=1) at /var/tmp/portage/dev-libs/glib-2.44.1-r1/work/glib-2.44.1/glib/gmain.c:3869 #17 0x00007ffff5dd1204 in QEventDispatcherGlib::processEvents (this=0x7fffdc0008c0, flags=...) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qeventdispatcher_glib.cpp:417 ---Type <return> to continue, or q <return> to quit--- #18 0x00007ffff5d74b5a in QEventLoop::exec (this=this@entry=0x7fffe21bede0, flags=..., flags@entry=...) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qeventloop.cpp:204 #19 0x00007ffff5b91ded in QThread::exec (this=this@entry= 0x7ffff7fb71c0 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/thread/qthread.cpp:503 #20 0x00007ffff7f3f315 in QDBusConnectionManager::run (this= 0x7ffff7fb71c0 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at /var/tmp/portage/dev-qt/qtdbus-5.6.9999/work/qtdbus-5.6.9999/src/dbus/qdbusconnection.cpp:181 #21 0x00007ffff5b976d2 in QThreadPrivate::start ( arg=0x7ffff7fb71c0 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/thread/qthread_unix.cpp:340 #22 0x00007ffff55a04dc in start_thread (arg=0x7fffe21bf700) at pthread_create.c:333 #23 0x00007ffff790e8cd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109
And just FYI, after this fugly patch to powerdevil, the problem only moves to other services: --- a/daemon/kdedpowerdevil.cpp +++ b/daemon/kdedpowerdevil.cpp @@ -45,7 +45,7 @@ KDEDPowerDevil::KDEDPowerDevil(QObject* parent, const QVariantList &) : KDEDModule(parent) , m_core(Q_NULLPTR) { - QTimer::singleShot(0, this, SLOT(init())); + QTimer::singleShot(3000, this, SLOT(init())); For example, I now get this from the touchpad module: Thread 3 (Thread 0x7fffe21bf700 (LWP 94561)): #0 pthread_cond_wait () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185 #1 0x00007ffff5b97e93 in wait (time=18446744073709551615, this=0x7fffdc014b80) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/thread/qwaitcondition_unix.cpp:136 #2 QWaitCondition::wait (this=this@entry=0x7fffdc003028, mutex=mutex@entry=0x7fffdc003020, time=time@entry=18446744073709551615) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/thread/qwaitcondition_unix.cpp:208 #3 0x00007ffff5b90343 in QSemaphore::acquire (this=this@entry=0x7fffe21be8f0, n=n@entry=1) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/thread/qsemaphore.cpp:137 #4 0x00007ffff7f52c8f in QDBusConnectionPrivate::handleObjectCall (this=0x7fffdc0030f0, msg=...) at /var/tmp/portage/dev-qt/qtdbus-5.6.9999/work/qtdbus-5.6.9999/src/dbus/qdbusintegrator.cpp:1506 #5 0x00007ffff5da7b3a in QObject::event (this=0x7fffdc0030f0, e=<optimized out>) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qobject.cpp:1256 #6 0x00007ffff5d764f5 in doNotify (receiver=<optimized out>, event=<optimized out>) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.cpp:1091 #7 0x00007ffff5d76678 in notify (event=<optimized out>, receiver=<optimized out>, this=<optimized out>) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.cpp:1077 #8 QCoreApplication::notifyInternal2 (receiver=0x7fffdc0030f0, event=event@entry=0x555555b94540) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.cpp:1016 #9 0x00007ffff5d79287 in sendEvent (event=0x555555b94540, receiver=<optimized out>) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.h:227 #10 QCoreApplicationPrivate::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0, data=0x5555557ba7d0) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.cpp:1651 #11 0x00007ffff5d7989e in QCoreApplication::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.cpp:1509 #12 0x00007ffff5dd1139 in postEventSourceDispatch (s=0x7fffdc0012d0) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qeventdispatcher_glib.cpp:270 #13 0x00007ffff2d0f08c in g_main_dispatch (context=0x7fffdc000990) at /var/tmp/portage/dev-libs/glib-2.44.1-r1/work/glib-2.44.1/glib/gmain.c:3122 #14 g_main_context_dispatch (context=context@entry=0x7fffdc000990) at /var/tmp/portage/dev-libs/glib-2.44.1-r1/work/glib-2.44.1/glib/gmain.c:3737 #15 0x00007ffff2d0f398 in g_main_context_iterate (context=context@entry=0x7fffdc000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.44.1-r1/work/glib-2.44.1/glib/gmain.c:3808 #16 0x00007ffff2d0f4a1 in g_main_context_iteration (context=0x7fffdc000990, may_block=1) at /var/tmp/portage/dev-libs/glib-2.44.1-r1/work/glib-2.44.1/glib/gmain.c:3869 #17 0x00007ffff5dd1204 in QEventDispatcherGlib::processEvents (this=0x7fffdc0008c0, flags=...) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qeventdispatcher_glib.cpp:417 ---Type <return> to continue, or q <return> to quit--- #18 0x00007ffff5d74b5a in QEventLoop::exec (this=this@entry=0x7fffe21bede0, flags=..., flags@entry=...) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qeventloop.cpp:204 #19 0x00007ffff5b91ded in QThread::exec (this=this@entry= 0x7ffff7fb71c0 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/thread/qthread.cpp:503 #20 0x00007ffff7f3f315 in QDBusConnectionManager::run (this= 0x7ffff7fb71c0 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at /var/tmp/portage/dev-qt/qtdbus-5.6.9999/work/qtdbus-5.6.9999/src/dbus/qdbusconnection.cpp:181 #21 0x00007ffff5b976d2 in QThreadPrivate::start ( arg=0x7ffff7fb71c0 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/thread/qthread_unix.cpp:340 #22 0x00007ffff55a04dc in start_thread (arg=0x7fffe21bf700) at pthread_create.c:333 #23 0x00007ffff790e8cd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109 Thread 1 (Thread 0x7ffff7e9a780 (LWP 94041)): #0 pthread_cond_wait () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185 #1 0x00007ffff5b97e93 in wait (time=18446744073709551615, this=0x555555bb3970) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/thread/qwaitcondition_unix.cpp:136 #2 QWaitCondition::wait (this=this@entry=0x555555dad5d8, mutex=mutex@entry=0x555555dad5d0, time=time@entry=18446744073709551615) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/thread/qwaitcondition_unix.cpp:208 #3 0x00007ffff5b90343 in QSemaphore::acquire (this=this@entry=0x7fffffffcaf0, n=n@entry=1) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/thread/qsemaphore.cpp:137 #4 0x00007ffff5da65f2 in QMetaObject::activate (sender=sender@entry=0x7fffdc0030f0, signalOffset=<optimized out>, local_signal_index=local_signal_index@entry=5, argv=argv@entry=0x7fffffffcb80) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qobject.cpp:3698 #5 0x00007ffff5da6fa5 in QMetaObject::activate (sender=sender@entry=0x7fffdc0030f0, m=m@entry=0x7ffff7fb6d40 <QDBusConnectionPrivate::staticMetaObject>, local_signal_index=local_signal_index@entry=5, argv=argv@entry=0x7fffffffcb80) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qobject.cpp:3595 #6 0x00007ffff7f9f52f in QDBusConnectionPrivate::signalNeedsDisconnecting (this=this@entry=0x7fffdc0030f0, _t1=..., _t2=...) at .moc/moc_qdbusconnection_p.cpp:345 #7 0x00007ffff7f4b883 in QDBusConnectionPrivate::disconnectSignal (this=this@entry=0x7fffdc0030f0, service=..., path=..., interface=..., name=..., argumentMatch=..., signature=..., receiver=0x55555596bf48, slot=0x7ffff7fa2c00 "1_q_serviceOwnerChanged(QString,QString,QString)") at /var/tmp/portage/dev-qt/qtdbus-5.6.9999/work/qtdbus-5.6.9999/src/dbus/qdbusintegrator.cpp:2188 #8 0x00007ffff7f4ba6f in QDBusConnectionPrivate::unwatchService (this=0x7fffdc0030f0, service=..., mode=..., obj=<optimized out>, member=member@entry=0x7ffff7fa2c00 "1_q_serviceOwnerChanged(QString,QString,QString)") at /var/tmp/portage/dev-qt/qtdbus-5.6.9999/work/qtdbus-5.6.9999/src/dbus/qdbusintegrator.cpp:2383 #9 0x00007ffff7f9ce0e in QDBusServiceWatcherPrivate::removeService (this=this@entry=0x555555bc5670, service=...) at /var/tmp/portage/dev-qt/qtdbus-5.6.9999/work/qtdbus-5.6.9999/src/dbus/qdbusservicewatcher.cpp:107 #10 0x00007ffff7f9d888 in QDBusServiceWatcher::removeWatchedService (this=this@entry=0x55555596bf48, service=...) at /var/tmp/portage/dev-qt/qtdbus-5.6.9999/work/qtdbus-5.6.9999/src/dbus/qdbusservicewatcher.cpp:296 #11 0x00007fffc31ef72c in TouchpadDisabler::serviceRegistered (this=this@entry=0x55555596bee0, service=...) ---Type <return> to continue, or q <return> to quit--- at /var/tmp/portage/kde-plasma/plasma-desktop-9999/work/plasma-desktop-9999/kcms/touchpad/src/kded/kded.cpp:35 #12 0x00007fffc31efadf in TouchpadDisabler::serviceNameFetchFinished (this=0x55555596bee0, callWatcher=<optimized out>) at /var/tmp/portage/kde-plasma/plasma-desktop-9999/work/plasma-desktop-9999/kcms/touchpad/src/kded/kded.cpp:98 #13 0x00007fffc31ff4bc in TouchpadDisabler::qt_static_metacall (_o=<optimized out>, _c=<optimized out>, _id=<optimized out>, _a=<optimized out>) at /var/tmp/portage/kde-plasma/plasma-desktop-9999/work/plasma-desktop-9999_build/kcms/touchpad/src/moc_kded.cpp:161 #14 0x00007ffff5da6365 in QMetaObject::activate (sender=0x555555dad450, signalOffset=<optimized out>, local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x7fffffffd020) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qobject.cpp:3730 #15 0x00007ffff5da6fa5 in QMetaObject::activate (sender=<optimized out>, m=m@entry=0x7ffff7fb6840 <QDBusPendingCallWatcher::staticMetaObject>, local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x7fffffffd020) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qobject.cpp:3595 #16 0x00007ffff7f9a69c in QDBusPendingCallWatcher::finished (this=<optimized out>, _t1=0x555555dad450) at .moc/moc_qdbuspendingcall.cpp:152 #17 0x00007ffff7f9a7b0 in _q_finished (this=<optimized out>) at /var/tmp/portage/dev-qt/qtdbus-5.6.9999/work/qtdbus-5.6.9999/src/dbus/qdbuspendingcall.cpp:488 #18 QDBusPendingCallWatcher::qt_static_metacall (_o=<optimized out>, _c=<optimized out>, _id=<optimized out>, _a=<optimized out>) at .moc/moc_qdbuspendingcall.cpp:83 #19 0x00007ffff5da7b3a in QObject::event (this=0x555555dad450, e=<optimized out>) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qobject.cpp:1256 #20 0x00007ffff725fe54 in QApplicationPrivate::notify_helper (this=<optimized out>, receiver=0x555555dad450, e=0x7fffdc053750) at /var/tmp/portage/dev-qt/qtwidgets-5.6.9999/work/qtwidgets-5.6.9999/src/widgets/kernel/qapplication.cpp:3771 #21 0x00007ffff7264c9e in QApplication::notify (this=0x7fffffffd750, receiver=0x555555dad450, e=0x7fffdc053750) at /var/tmp/portage/dev-qt/qtwidgets-5.6.9999/work/qtwidgets-5.6.9999/src/widgets/kernel/qapplication.cpp:3528 #22 0x00007ffff5d766d8 in QCoreApplication::notifyInternal2 (receiver=0x555555dad450, event=event@entry=0x7fffdc053750) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.cpp:1016 #23 0x00007ffff5d79287 in sendEvent (event=0x7fffdc053750, receiver=<optimized out>) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.h:227 #24 QCoreApplicationPrivate::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0, data=0x555555756db0) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.cpp:1651 #25 0x00007ffff5d7989e in QCoreApplication::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.cpp:1509 #26 0x00007ffff5dd1139 in postEventSourceDispatch (s=0x55555579b190) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qeventdispatcher_glib.cpp:270 #27 0x00007ffff2d0f08c in g_main_dispatch (context=0x7fffe4002450) at /var/tmp/portage/dev-libs/glib-2.44.1-r1/work/glib-2.44.1/glib/gmain.c:3122 #28 g_main_context_dispatch (context=context@entry=0x7fffe4002450) at /var/tmp/portage/dev-libs/glib-2.44.1-r1/work/glib-2.44.1/glib/gmain.c:3737 #29 0x00007ffff2d0f398 in g_main_context_iterate (context=context@entry=0x7fffe4002450, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.44.1-r1/work/glib-2.44.1/glib/gmain.c:3808 #30 0x00007ffff2d0f4a1 in g_main_context_iteration (context=0x7fffe4002450, may_block=1) at /var/tmp/portage/dev-libs/glib-2.44.1-r1/work/glib-2.44.1/glib/gmain.c:3869 #31 0x00007ffff5dd11ed in QEventDispatcherGlib::processEvents (this=0x5555557a19f0, flags=...) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qeventdispatcher_glib.cpp:417 #32 0x00007ffff5d74b5a in QEventLoop::exec (this=this@entry=0x7fffffffd620, flags=..., flags@entry=...) at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qeventloop.cpp:204 #33 0x00007ffff5d7db96 in QCoreApplication::exec () at /var/tmp/portage/dev-qt/qtcore-5.6.9999/work/qtcore-5.6.9999/src/corelib/kernel/qcoreapplication.cpp:1286 #34 0x00007ffff65ceeda in QGuiApplication::exec () at /var/tmp/portage/dev-qt/qtgui-5.6.9999/work/qtgui-5.6.9999/src/gui/kernel/qguiapplication.cpp:1601 #35 0x00007ffff725c30b in QApplication::exec () at /var/tmp/portage/dev-qt/qtwidgets-5.6.9999/work/qtwidgets-5.6.9999/src/widgets/kernel/qapplication.cpp:2974 #36 0x00007ffff7bd11e7 in kdemain (argc=1, argv=<optimized out>) at /var/tmp/portage/kde-frameworks/kded-9999/work/kded-9999/src/kded.cpp:767 #37 0x00007ffff783a9e4 in __libc_start_main (main=0x5555555548b0 <main(int, char**)>, argc=1, argv=0x7fffffffd918, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffffffd908) at libc-start.c:297 #38 0x0000555555554919 in _start ()
Might be https://bugreports.qt.io/browse/QTBUG-51676
Thanks, Thiago -- the patch linked patch (https://codereview.qt-project.org/#/c/151459/3) fixes the problem for me.
The patch is in upstream's 5.6 branch and will be released with the 5.6.1 release.
*** Bug 363488 has been marked as a duplicate of this bug. ***