Application: plasmashell (5.5.5)

Qt Version: 5.5.1
Operating System: Linux 4.4.0-21-generic x86_64
Distribution: Ubuntu 16.04 LTS

-- Information about the crash:
My desktop computer running Kubuntu 16.04 is set to automatically lock. After it locks, I log in from the lock screen, and Crash Reporting Assistant windows are waiting for me. I've left my computer locked overnight before, and in the morning, I find hundreds of crash windows after logging in. One other thing that does happen consistently is that my widgets dissappear after logging in. I am able to make them reappear by opening the "Add Widgets" drawer. Apart from this, Plasma is completely useable.

-- Backtrace:
Application: Plasma (plasmashell), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f3e4eb328c0 (LWP 5547))]

Thread 8 (Thread 0x7f3e39e54700 (LWP 5550)):
#0  0x00007f3e49244e8d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007f3e4d309c62 in  () at /usr/lib/x86_64-linux-gnu/libxcb.so.1
#2  0x00007f3e4d30b8d7 in xcb_wait_for_event () at /usr/lib/x86_64-linux-gnu/libxcb.so.1
#3  0x00007f3e3bfa2629 in  () at /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#4  0x00007f3e4993a84e in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f3e48a276fa in start_thread (arg=0x7f3e39e54700) at pthread_create.c:333
#6  0x00007f3e49250b5d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 7 (Thread 0x7f3e335ef700 (LWP 5552)):
#0  0x00007f3e4601ea49 in g_mutex_lock (mutex=mutex@entry=0x7f3e2c000990) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gthread-posix.c:1338
#1  0x00007f3e45fd9ad1 in g_main_context_query (context=context@entry=0x7f3e2c000990, max_priority=2147483647, timeout=timeout@entry=0x7f3e335eebb4, fds=fds@entry=0x7f3e2c003070, n_fds=n_fds@entry=1) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:3544
#2  0x00007f3e45fda297 in g_main_context_iterate (context=context@entry=0x7f3e2c000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:3822
#3  0x00007f3e45fda42c in g_main_context_iteration (context=0x7f3e2c000990, may_block=1) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:3901
#4  0x00007f3e49b71a9b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f3e49b18dea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f3e499358a4 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f3e4c1dd3c5 in  () at /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#8  0x00007f3e4993a84e in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007f3e48a276fa in start_thread (arg=0x7f3e335ef700) at pthread_create.c:333
#10 0x00007f3e49250b5d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 6 (Thread 0x7f3e27fcd700 (LWP 5553)):
#0  0x00007f3e492409cd in read () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007f3e4601d6c0 in g_wakeup_acknowledge (__nbytes=16, __buf=0x7f3e27fccae0, __fd=<optimized out>) at /usr/include/x86_64-linux-gnu/bits/unistd.h:44
#2  0x00007f3e4601d6c0 in g_wakeup_acknowledge (wakeup=0x7f3e2c0025a0) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gwakeup.c:210
#3  0x00007f3e45fd9e04 in g_main_context_check (context=context@entry=0x7f3e20000990, max_priority=2147483647, fds=fds@entry=0x7f3e20002e70, n_fds=n_fds@entry=1) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:3632
#4  0x00007f3e45fda2c0 in g_main_context_iterate (context=context@entry=0x7f3e20000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:3837
#5  0x00007f3e45fda42c in g_main_context_iteration (context=0x7f3e20000990, may_block=1) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:3901
#6  0x00007f3e49b71a9b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f3e49b18dea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f3e499358a4 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007f3e4c1dd3c5 in  () at /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#10 0x00007f3e4993a84e in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#11 0x00007f3e48a276fa in start_thread (arg=0x7f3e27fcd700) at pthread_create.c:333
#12 0x00007f3e49250b5d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 5 (Thread 0x7f3e2621a700 (LWP 5554)):
#0  0x00007f3e49244e8d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007f3e45fda31c in g_main_context_iterate (priority=2147483647, n_fds=1, fds=0x7f3e18003070, timeout=<optimized out>, context=0x7f3e18000990) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:4135
#2  0x00007f3e45fda31c in g_main_context_iterate (context=context@entry=0x7f3e18000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:3835
#3  0x00007f3e45fda42c in g_main_context_iteration (context=0x7f3e18000990, may_block=1) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:3901
#4  0x00007f3e49b71a9b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f3e49b18dea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f3e499358a4 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f3e4c1dd3c5 in  () at /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#8  0x00007f3e4993a84e in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007f3e48a276fa in start_thread (arg=0x7f3e2621a700) at pthread_create.c:333
#10 0x00007f3e49250b5d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 4 (Thread 0x7f3e248c7700 (LWP 5555)):
#0  0x00007f3e48a2d3a0 in pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007f3e4e582bd4 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#2  0x00007f3e4e582c19 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#3  0x00007f3e48a276fa in start_thread (arg=0x7f3e248c7700) at pthread_create.c:333
#4  0x00007f3e49250b5d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 3 (Thread 0x7f3e1cf06700 (LWP 5557)):
#0  0x00007f3e49244e8d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007f3e45fda31c in g_main_context_iterate (priority=2147483647, n_fds=1, fds=0x7f3d94003120, timeout=<optimized out>, context=0x7f3d94000990) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:4135
#2  0x00007f3e45fda31c in g_main_context_iterate (context=context@entry=0x7f3d94000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:3835
#3  0x00007f3e45fda42c in g_main_context_iteration (context=0x7f3d94000990, may_block=1) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:3901
#4  0x00007f3e49b71a9b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f3e49b18dea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f3e499358a4 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f3e4cb63ed6 in  () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#8  0x00007f3e4993a84e in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007f3e48a276fa in start_thread (arg=0x7f3e1cf06700) at pthread_create.c:333
#10 0x00007f3e49250b5d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 2 (Thread 0x7f3d858bc700 (LWP 5558)):
#0  0x00007f3e49244e8d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007f3e45fda31c in g_main_context_iterate (priority=2147483647, n_fds=1, fds=0x7f3d800048c0, timeout=<optimized out>, context=0x7f3d80000990) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:4135
#2  0x00007f3e45fda31c in g_main_context_iterate (context=context@entry=0x7f3d80000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:3835
#3  0x00007f3e45fda42c in g_main_context_iteration (context=0x7f3d80000990, may_block=1) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:3901
#4  0x00007f3e49b71a9b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f3e49b18dea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f3e499358a4 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f3d87d9c7d7 in KCupsConnection::run() () at /usr/lib/x86_64-linux-gnu/libkcupslib.so
#8  0x00007f3e4993a84e in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007f3e48a276fa in start_thread (arg=0x7f3d858bc700) at pthread_create.c:333
#10 0x00007f3e49250b5d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 1 (Thread 0x7f3e4eb328c0 (LWP 5547)):
[KCrash Handler]
#6  0x00007f3e4d081420 in Plasma::Applet::actions() const () at /usr/lib/x86_64-linux-gnu/libKF5Plasma.so.5
#7  0x00000000004559b2 in ShellCorona::addOutput(QSharedPointer<KScreen::Output> const&) ()
#8  0x0000000000455b4f in ShellCorona::outputEnabledChanged() ()
#9  0x00007f3e49b49e4f in QMetaObject::activate(QObject*, int, int, void**) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#10 0x00007f3e4dd02c59 in KScreen::Output::apply(QSharedPointer<KScreen::Output> const&) () at /usr/lib/x86_64-linux-gnu/libKF5Screen.so.6
#11 0x00007f3e4dcf25d5 in KScreen::Config::apply(QSharedPointer<KScreen::Config> const&) () at /usr/lib/x86_64-linux-gnu/libKF5Screen.so.6
#12 0x00007f3e4dcf7cc9 in KScreen::ConfigMonitor::Private::updateConfigs(QSharedPointer<KScreen::Config> const&) () at /usr/lib/x86_64-linux-gnu/libKF5Screen.so.6
#13 0x00007f3e4dcf98ad in KScreen::ConfigMonitor::Private::edidReady(QDBusPendingCallWatcher*) () at /usr/lib/x86_64-linux-gnu/libKF5Screen.so.6
#14 0x00007f3e49b49e4f in QMetaObject::activate(QObject*, int, int, void**) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#15 0x00007f3e4ecb8f6f in QDBusPendingCallWatcher::finished(QDBusPendingCallWatcher*) () at /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#16 0x00007f3e4ecba645 in  () at /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#17 0x00007f3e49b4aea1 in QObject::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#18 0x00007f3e4a61e05c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#19 0x00007f3e4a623516 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#20 0x00007f3e49b1b62b in QCoreApplication::notifyInternal(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#21 0x00007f3e49b1da26 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#22 0x00007f3e49b71673 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#23 0x00007f3e45fda127 in g_main_context_dispatch (context=0x7f3e340016f0) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:3154
#24 0x00007f3e45fda127 in g_main_context_dispatch (context=context@entry=0x7f3e340016f0) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:3769
#25 0x00007f3e45fda380 in g_main_context_iterate (context=context@entry=0x7f3e340016f0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:3840
#26 0x00007f3e45fda42c in g_main_context_iteration (context=0x7f3e340016f0, may_block=1) at /build/glib2.0-t9oPgV/glib2.0-2.48.0/./glib/gmain.c:3901
#27 0x00007f3e49b71a7f in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#28 0x00007f3e49b18dea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#29 0x00007f3e49b20e8c in QCoreApplication::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#30 0x0000000000432d4a in main ()

Possible duplicates by query: bug 362184, bug 361730, bug 361506, bug 361247, bug 360912.

Reported using DrKonqi