Application: plasmashell (5.12.6)

Qt Version: 5.9.5
Frameworks Version: 5.44.0
Operating System: Linux 4.15.0-23-generic x86_64
Distribution: Ubuntu 18.04 LTS

-- Information about the crash:
- What I was doing when the application crashed:
logging in

- Unusual behavior I noticed:
Couldn't actually use plasma for anything. But ctrl-alt-del takes me to a logout/shutdown dialogue. If I logout, and log back in (this is kubuntu btw) twice more I can then finally use plasma as usual.

The crash can be reproduced every time.

-- 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 0x7fb9ecc15800 (LWP 16100))]

Thread 11 (Thread 0x7fb8fd9ff700 (LWP 16307)):
#0  0x00007fb9e5a0d9f3 in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x562cefc61c00) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x562cefc61bb0, cond=0x562cefc61bd8) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x562cefc61bd8, mutex=0x562cefc61bb0) at pthread_cond_wait.c:655
#3  0x00007fb9e689d59b in QWaitCondition::wait(QMutex*, unsigned long) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fb9ea66e548 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#5  0x00007fb9ea66e9aa in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#6  0x00007fb9e689c16d in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fb9e5a076db in start_thread (arg=0x7fb8fd9ff700) at pthread_create.c:463
#8  0x00007fb9e618988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 10 (Thread 0x7fb90822f700 (LWP 16302)):
#0  0x00007fb9e0cb1cf4 in g_mutex_unlock () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#1  0x00007fb9e0c6bdc8 in g_main_context_check () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fb9e0c6c3e0 in ?? () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fb9e0c6c54c in g_main_context_iteration () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007fb9e6ad390b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fb9e6a789ea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007fb9e689722a in QThread::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fb908907747 in KCupsConnection::run() () from /usr/lib/x86_64-linux-gnu/libkcupslib.so
#8  0x00007fb9e689c16d in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007fb9e5a076db in start_thread (arg=0x7fb90822f700) at pthread_create.c:463
#10 0x00007fb9e618988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 9 (Thread 0x7fb9226f7700 (LWP 16300)):
#0  0x00007fb9e61780b4 in __GI___libc_read (fd=36, buf=0x7fb9226f6b20, nbytes=16) at ../sysdeps/unix/sysv/linux/read.c:27
#1  0x00007fb9e0cb0960 in ?? () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fb9e0c6bf27 in g_main_context_check () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fb9e0c6c3e0 in ?? () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007fb9e0c6c54c in g_main_context_iteration () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007fb9e6ad390b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007fb9e6a789ea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fb9e689722a in QThread::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007fb9ea5ef2a6 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#9  0x00007fb9e689c16d in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#10 0x00007fb9e5a076db in start_thread (arg=0x7fb9226f7700) at pthread_create.c:463
#11 0x00007fb9e618988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 8 (Thread 0x7fb932adf700 (LWP 16299)):
#0  0x00007fb9e5a0d9f3 in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x562cee7afd64) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x562cee7afd10, cond=0x562cee7afd38) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x562cee7afd38, mutex=0x562cee7afd10) at pthread_cond_wait.c:655
#3  0x00007fb9e689d59b in QWaitCondition::wait(QMutex*, unsigned long) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fb9ea66e548 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#5  0x00007fb9ea66e9aa in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#6  0x00007fb9e689c16d in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fb9e5a076db in start_thread (arg=0x7fb932adf700) at pthread_create.c:463
#8  0x00007fb9e618988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 7 (Thread 0x7fb9322de700 (LWP 16283)):
#0  0x00007fb9e5a0d9f3 in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x562cee68b194) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x562cee68b140, cond=0x562cee68b168) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x562cee68b168, mutex=0x562cee68b140) at pthread_cond_wait.c:655
#3  0x00007fb9e689d59b in QWaitCondition::wait(QMutex*, unsigned long) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fb9ea66e548 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#5  0x00007fb9ea66e9aa in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#6  0x00007fb9e689c16d in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fb9e5a076db in start_thread (arg=0x7fb9322de700) at pthread_create.c:463
#8  0x00007fb9e618988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 6 (Thread 0x7fb9c6187700 (LWP 16157)):
#0  0x00007fb9e5a0d9f3 in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7fb9ec5e0fb8) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x7fb9ec5e0f68, cond=0x7fb9ec5e0f90) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x7fb9ec5e0f90, mutex=0x7fb9ec5e0f68) at pthread_cond_wait.c:655
#3  0x00007fb9ec2ea5f4 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#4  0x00007fb9ec2ea639 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#5  0x00007fb9e5a076db in start_thread (arg=0x7fb9c6187700) at pthread_create.c:463
#6  0x00007fb9e618988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 5 (Thread 0x7fb9c7fff700 (LWP 16149)):
#0  0x00007fb9e617cbf9 in __GI___poll (fds=0x7fb9bc003ce0, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007fb9e0c6c439 in ?? () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fb9e0c6c54c in g_main_context_iteration () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fb9e6ad390b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fb9e6a789ea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fb9e689722a in QThread::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007fb9e9a406f5 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#7  0x00007fb9e689c16d in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007fb9e5a076db in start_thread (arg=0x7fb9c7fff700) at pthread_create.c:463
#9  0x00007fb9e618988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 4 (Thread 0x7fb9ce5a7700 (LWP 16147)):
#0  0x00007fb9e61780b4 in __GI___libc_read (fd=13, buf=0x7fb9ce5a6b70, nbytes=16) at ../sysdeps/unix/sysv/linux/read.c:27
#1  0x00007fb9e0cb0960 in ?? () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fb9e0c6bf27 in g_main_context_check () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fb9e0c6c3e0 in ?? () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007fb9e0c6c54c in g_main_context_iteration () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007fb9e6ad390b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007fb9e6a789ea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fb9e689722a in QThread::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007fb9e9a406f5 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#9  0x00007fb9e689c16d in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#10 0x00007fb9e5a076db in start_thread (arg=0x7fb9ce5a7700) at pthread_create.c:463
#11 0x00007fb9e618988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 3 (Thread 0x7fb9cffff700 (LWP 16136)):
#0  0x00007fffa11bb979 in ?? ()
#1  0x00007fffa11bbc30 in clock_gettime ()
#2  0x00007fb9e6198ea6 in __GI___clock_gettime (clock_id=1, tp=0x7fb9cfffeae0) at ../sysdeps/unix/clock_gettime.c:115
#3  0x00007fb9e6ad3221 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fb9e6ad1a59 in QTimerInfoList::updateCurrentTime() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fb9e6ad2035 in QTimerInfoList::timerWait(timespec&) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007fb9e6ad367e in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fb9e0c6b998 in g_main_context_prepare () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#8  0x00007fb9e0c6c36b in ?? () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#9  0x00007fb9e0c6c54c in g_main_context_iteration () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#10 0x00007fb9e6ad390b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#11 0x00007fb9e6a789ea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#12 0x00007fb9e689722a in QThread::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#13 0x00007fb9e6f55d45 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#14 0x00007fb9e689c16d in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#15 0x00007fb9e5a076db in start_thread (arg=0x7fb9cffff700) at pthread_create.c:463
#16 0x00007fb9e618988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7fb9d67bf700 (LWP 16122)):
#0  0x00007fb9e617cbf9 in __GI___poll (fds=0x7fb9d67beca8, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007fb9eb203747 in ?? () from /usr/lib/x86_64-linux-gnu/libxcb.so.1
#2  0x00007fb9eb20536a in xcb_wait_for_event () from /usr/lib/x86_64-linux-gnu/libxcb.so.1
#3  0x00007fb9d91922a9 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#4  0x00007fb9e689c16d in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fb9e5a076db in start_thread (arg=0x7fb9d67bf700) at pthread_create.c:463
#6  0x00007fb9e618988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7fb9ecc15800 (LWP 16100)):
[KCrash Handler]
#6  0x00007fb9ea60d268 in QQuickAnimatorProxyJob::sceneGraphInitialized() () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#7  0x00007fb9e6aaa122 in QObject::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007fb9e7a9482c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#9  0x00007fb9e7a9c0f4 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#10 0x00007fb9e6a7a9a8 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#11 0x00007fb9e6a7d11d in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#12 0x00007fb9e6ad42c3 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#13 0x00007fb9e0c6c287 in g_main_context_dispatch () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#14 0x00007fb9e0c6c4c0 in ?? () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#15 0x00007fb9e0c6c54c in g_main_context_iteration () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#16 0x00007fb9e6ad38ef in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#17 0x00007fb9e6a789ea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#18 0x00007fb9e6a81a84 in QCoreApplication::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#19 0x0000562ced720cfa in ?? ()
#20 0x00007fb9e6089b97 in __libc_start_main (main=0x562ced720320, argc=1, argv=0x7fffa115cf88, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffa115cf78) at ../csu/libc-start.c:310
#21 0x0000562ced72109a in _start ()

Possible duplicates by query: bug 396782, bug 390318, bug 390273, bug 389507, bug 388639.

Reported using DrKonqi