405921 – Plasma crashes when dragging task from taskmanager to a different virtual desktop

Bug 405921 - Plasma crashes when dragging task from taskmanager to a different virtual desktop

Summary: Plasma crashes when dragging task from taskmanager to a different virtual des...

Status:	RESOLVED DUPLICATE of bug 415423

Alias:	None

Product:	plasmashell
Classification:	Plasma
Component:	Task Manager and Icons-Only Task Manager (show other bugs)
Version:	5.15.3
Platform:	Compiled Sources Linux

Importance:	NOR crash
Target Milestone:	1.0
Assignee:	Eike Hein

URL:
Keywords:	drkonqi

Depends on:
Blocks:

Reported:	2019-03-27 06:24 UTC by Franz Trischberger
Modified:	2020-01-28 18:20 UTC (History)
CC List:	4 users (show)

See Also:
Latest Commit:
Version Fixed In:

Attachments
New crash information added by DrKonqi (23.49 KB, text/plain) 2019-09-21 06:59 UTC, Franz Trischberger	Details
New crash information added by DrKonqi (26.33 KB, patch) 2020-01-02 16:01 UTC, Franz Trischberger	Details
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Description Franz Trischberger 2019-03-27 06:24:16 UTC

Application: plasmashell (5.15.3)
 (Compiled from sources)
Qt Version: 5.12.2
Frameworks Version: 5.56.0
Operating System: Linux 4.19.27-gentoo-r1 x86_64
Distribution: "Gentoo Base System release 2.6"

-- Information about the crash:
- What I was doing when the application crashed:
I wanted to move a konsole window from VT 1 to VT 2. So I wanted to dragged the task from the taskmanager (the default window list in the bottom panel, hope that's how it is called) to a different desktop in the VT-Plasmoid. This worked in the past, now it crashes.

The crash can be reproduced every time.

-- Backtrace:
Application: Plasma (plasmashell), signal: Segmentation fault
Using host libthread_db library "/lib64/libthread_db.so.1".
[Current thread is 1 (Thread 0x7ff98aa2d340 (LWP 616))]

Thread 11 (Thread 0x7ff9270e9700 (LWP 1284)):
#0  0x00007ff976ea2db6 in pa_atomic_load (a=<optimized out>) at /var/tmp/portage/media-sound/pulseaudio-12.2/work/pulseaudio-12.2/src/pulsecore/pstream.c:855
#1  do_read (p=p@entry=0x7ff910000bc0, re=re@entry=0x7ff910000d88) at /var/tmp/portage/media-sound/pulseaudio-12.2/work/pulseaudio-12.2/src/pulsecore/pstream.c:856
#2  0x00007ff976ea5cdb in do_pstream_read_write (p=0x7ff910000bc0) at /var/tmp/portage/media-sound/pulseaudio-12.2/work/pulseaudio-12.2/src/pulsecore/pstream.c:248
#3  0x00007ff976ea6079 in srb_callback (srb=0x7ff910004090, userdata=0x7ff910000bc0) at /var/tmp/portage/media-sound/pulseaudio-12.2/work/pulseaudio-12.2/src/pulsecore/pstream.c:287
#4  0x00007ff976ea68ca in srbchannel_rwloop (sr=0x7ff910004090) at /var/tmp/portage/media-sound/pulseaudio-12.2/work/pulseaudio-12.2/src/pulsecore/srbchannel.c:190
#5  0x00007ff97ba5fb98 in dispatch_pollfds (m=0xa6dbf80) at /var/tmp/portage/media-sound/pulseaudio-12.2/work/pulseaudio-12.2/src/pulse/mainloop.c:140
#6  pa_mainloop_dispatch (m=m@entry=0xa6dbf80) at /var/tmp/portage/media-sound/pulseaudio-12.2/work/pulseaudio-12.2/src/pulse/mainloop.c:898
#7  0x00007ff97ba5fe6c in pa_mainloop_iterate (m=0xa6dbf80, block=<optimized out>, retval=0x0) at /var/tmp/portage/media-sound/pulseaudio-12.2/work/pulseaudio-12.2/src/pulse/mainloop.c:929
#8  0x00007ff97ba5ff10 in pa_mainloop_run (m=0xa6dbf80, retval=retval@entry=0x0) at /var/tmp/portage/media-sound/pulseaudio-12.2/work/pulseaudio-12.2/src/pulse/mainloop.c:945
#9  0x00007ff97ba6df59 in thread (userdata=0xa690f50) at /var/tmp/portage/media-sound/pulseaudio-12.2/work/pulseaudio-12.2/src/pulse/thread-mainloop.c:100
#10 0x00007ff976eb68d8 in internal_thread_func (userdata=0xa736cc0) at /var/tmp/portage/media-sound/pulseaudio-12.2/work/pulseaudio-12.2/src/pulsecore/thread-posix.c:81
#11 0x00007ff98113d96a in start_thread (arg=0x7ff9270e9700) at pthread_create.c:463
#12 0x00007ff983f261bf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 10 (Thread 0x7ff927d99700 (LWP 1283)):
#0  0x00007ff98114456c in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x9098714) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x90986c0, cond=0x90986e8) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x90986e8, mutex=0x90986c0) at pthread_cond_wait.c:655
#3  0x00007ff9846b3573 in QWaitConditionPrivate::wait (deadline=..., this=0x90986c0) at thread/qwaitcondition_unix.cpp:146
#4  QWaitCondition::wait (this=<optimized out>, mutex=0x7ff96c00f3f0, deadline=...) at thread/qwaitcondition_unix.cpp:225
#5  0x00007ff9846b35f9 in QWaitCondition::wait (this=this@entry=0x7ff96c00f3f8, mutex=mutex@entry=0x7ff96c00f3f0, time=time@entry=18446744073709551615) at ../../include/QtCore/../../src/corelib/kernel/qdeadlinetimer.h:68
#6  0x00007ff9888c71c9 in QSGRenderThreadEventQueue::takeEvent (wait=true, this=0x7ff96c00f3e8) at scenegraph/qsgthreadedrenderloop.cpp:245
#7  QSGRenderThread::processEventsAndWaitForMore (this=this@entry=0x7ff96c00f370) at scenegraph/qsgthreadedrenderloop.cpp:710
#8  0x00007ff9888c742a in QSGRenderThread::run (this=0x7ff96c00f370) at scenegraph/qsgthreadedrenderloop.cpp:739
#9  0x00007ff9846add52 in QThreadPrivate::start (arg=0x7ff96c00f370) at thread/qthread_unix.cpp:361
#10 0x00007ff98113d96a in start_thread (arg=0x7ff927d99700) at pthread_create.c:463
#11 0x00007ff983f261bf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 9 (Thread 0x7ff940837700 (LWP 785)):
#0  0x00007ff98114456c in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x77e0ed0) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x77e0e80, cond=0x77e0ea8) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x77e0ea8, mutex=0x77e0e80) at pthread_cond_wait.c:655
#3  0x00007ff9846b3573 in QWaitConditionPrivate::wait (deadline=..., this=0x77e0e80) at thread/qwaitcondition_unix.cpp:146
#4  QWaitCondition::wait (this=<optimized out>, mutex=0x785a520, deadline=...) at thread/qwaitcondition_unix.cpp:225
#5  0x00007ff9846b35f9 in QWaitCondition::wait (this=this@entry=0x785a528, mutex=mutex@entry=0x785a520, time=time@entry=18446744073709551615) at ../../include/QtCore/../../src/corelib/kernel/qdeadlinetimer.h:68
#6  0x00007ff9888c71c9 in QSGRenderThreadEventQueue::takeEvent (wait=true, this=0x785a518) at scenegraph/qsgthreadedrenderloop.cpp:245
#7  QSGRenderThread::processEventsAndWaitForMore (this=this@entry=0x785a4a0) at scenegraph/qsgthreadedrenderloop.cpp:710
#8  0x00007ff9888c742a in QSGRenderThread::run (this=0x785a4a0) at scenegraph/qsgthreadedrenderloop.cpp:739
#9  0x00007ff9846add52 in QThreadPrivate::start (arg=0x785a4a0) at thread/qthread_unix.cpp:361
#10 0x00007ff98113d96a in start_thread (arg=0x7ff940837700) at pthread_create.c:463
#11 0x00007ff983f261bf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 8 (Thread 0x7ff941587700 (LWP 779)):
#0  0x00007ff98114456c in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x39cff20) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x39cfed0, cond=0x39cfef8) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x39cfef8, mutex=0x39cfed0) at pthread_cond_wait.c:655
#3  0x00007ff9846b3573 in QWaitConditionPrivate::wait (deadline=..., this=0x39cfed0) at thread/qwaitcondition_unix.cpp:146
#4  QWaitCondition::wait (this=<optimized out>, mutex=0x39d1f30, deadline=...) at thread/qwaitcondition_unix.cpp:225
#5  0x00007ff9846b35f9 in QWaitCondition::wait (this=this@entry=0x39d1f38, mutex=mutex@entry=0x39d1f30, time=time@entry=18446744073709551615) at ../../include/QtCore/../../src/corelib/kernel/qdeadlinetimer.h:68
#6  0x00007ff9888c71c9 in QSGRenderThreadEventQueue::takeEvent (wait=true, this=0x39d1f28) at scenegraph/qsgthreadedrenderloop.cpp:245
#7  QSGRenderThread::processEventsAndWaitForMore (this=this@entry=0x39d1eb0) at scenegraph/qsgthreadedrenderloop.cpp:710
#8  0x00007ff9888c742a in QSGRenderThread::run (this=0x39d1eb0) at scenegraph/qsgthreadedrenderloop.cpp:739
#9  0x00007ff9846add52 in QThreadPrivate::start (arg=0x39d1eb0) at thread/qthread_unix.cpp:361
#10 0x00007ff98113d96a in start_thread (arg=0x7ff941587700) at pthread_create.c:463
#11 0x00007ff983f261bf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 7 (Thread 0x7ff942050700 (LWP 778)):
#0  0x00007ff98114456c in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x346fd94) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x346fd40, cond=0x346fd68) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x346fd68, mutex=0x346fd40) at pthread_cond_wait.c:655
#3  0x00007ff9846b3573 in QWaitConditionPrivate::wait (deadline=..., this=0x346fd40) at thread/qwaitcondition_unix.cpp:146
#4  QWaitCondition::wait (this=<optimized out>, mutex=0x33bd200, deadline=...) at thread/qwaitcondition_unix.cpp:225
#5  0x00007ff9846b35f9 in QWaitCondition::wait (this=this@entry=0x33bd208, mutex=mutex@entry=0x33bd200, time=time@entry=18446744073709551615) at ../../include/QtCore/../../src/corelib/kernel/qdeadlinetimer.h:68
#6  0x00007ff9888c71c9 in QSGRenderThreadEventQueue::takeEvent (wait=true, this=0x33bd1f8) at scenegraph/qsgthreadedrenderloop.cpp:245
#7  QSGRenderThread::processEventsAndWaitForMore (this=this@entry=0x33bd180) at scenegraph/qsgthreadedrenderloop.cpp:710
#8  0x00007ff9888c742a in QSGRenderThread::run (this=0x33bd180) at scenegraph/qsgthreadedrenderloop.cpp:739
#9  0x00007ff9846add52 in QThreadPrivate::start (arg=0x33bd180) at thread/qthread_unix.cpp:361
#10 0x00007ff98113d96a in start_thread (arg=0x7ff942050700) at pthread_create.c:463
#11 0x00007ff983f261bf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 6 (Thread 0x7ff9441c5700 (LWP 777)):
#0  0x00007ff98114456c in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x3e1c6a4) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x3e1c650, cond=0x3e1c678) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x3e1c678, mutex=0x3e1c650) at pthread_cond_wait.c:655
#3  0x00007ff9846b3573 in QWaitConditionPrivate::wait (deadline=..., this=0x3e1c650) at thread/qwaitcondition_unix.cpp:146
#4  QWaitCondition::wait (this=<optimized out>, mutex=0x3e18b20, deadline=...) at thread/qwaitcondition_unix.cpp:225
#5  0x00007ff9846b35f9 in QWaitCondition::wait (this=this@entry=0x3e18b28, mutex=mutex@entry=0x3e18b20, time=time@entry=18446744073709551615) at ../../include/QtCore/../../src/corelib/kernel/qdeadlinetimer.h:68
#6  0x00007ff9888c71c9 in QSGRenderThreadEventQueue::takeEvent (wait=true, this=0x3e18b18) at scenegraph/qsgthreadedrenderloop.cpp:245
#7  QSGRenderThread::processEventsAndWaitForMore (this=this@entry=0x3e18aa0) at scenegraph/qsgthreadedrenderloop.cpp:710
#8  0x00007ff9888c742a in QSGRenderThread::run (this=0x3e18aa0) at scenegraph/qsgthreadedrenderloop.cpp:739
#9  0x00007ff9846add52 in QThreadPrivate::start (arg=0x3e18aa0) at thread/qthread_unix.cpp:361
#10 0x00007ff98113d96a in start_thread (arg=0x7ff9441c5700) at pthread_create.c:463
#11 0x00007ff983f261bf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 5 (Thread 0x7ff95173e700 (LWP 768)):
#0  0x00007ff97de9b8d9 in g_source_iter_next (iter=iter@entry=0x7ff95173db10, source=source@entry=0x7ff95173db08) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gmain.c:969
#1  0x00007ff97de9e2f2 in g_main_context_check (context=context@entry=0x7ff94c000bf0, max_priority=2147483647, fds=fds@entry=0x7ff94c005480, n_fds=n_fds@entry=1) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gmain.c:3733
#2  0x00007ff97de9e970 in g_main_context_iterate (context=context@entry=0x7ff94c000bf0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gmain.c:3917
#3  0x00007ff97de9eadc in g_main_context_iteration (context=0x7ff94c000bf0, may_block=may_block@entry=1) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gmain.c:3981
#4  0x00007ff98488bf7b in QEventDispatcherGlib::processEvents (this=0x7ff94c000b20, flags=...) at kernel/qeventdispatcher_glib.cpp:424
#5  0x00007ff98483949b in QEventLoop::exec (this=this@entry=0x7ff95173dce0, flags=..., flags@entry=...) at ../../include/QtCore/../../src/corelib/global/qflags.h:140
#6  0x00007ff9846acb26 in QThread::exec (this=this@entry=0x7ff96400ccf0) at ../../include/QtCore/../../src/corelib/global/qflags.h:120
#7  0x00007ff988842ee6 in QQuickPixmapReader::run (this=0x7ff96400ccf0) at util/qquickpixmapcache.cpp:953
#8  0x00007ff9846add52 in QThreadPrivate::start (arg=0x7ff96400ccf0) at thread/qthread_unix.cpp:361
#9  0x00007ff98113d96a in start_thread (arg=0x7ff95173e700) at pthread_create.c:463
#10 0x00007ff983f261bf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 4 (Thread 0x7ff95f443700 (LWP 767)):
#0  0x00007ff98114456c in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x1f947fc) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  __pthread_cond_wait_common (abstime=0x0, mutex=0x1f947a8, cond=0x1f947d0) at pthread_cond_wait.c:502
#2  __pthread_cond_wait (cond=0x1f947d0, mutex=0x1f947a8) at pthread_cond_wait.c:655
#3  0x00007ff95f623fe3 in cnd_wait (mtx=0x1f947a8, cond=0x1f947d0) at ../mesa-18.3.5/src/../include/c11/threads_posix.h:155
#4  util_queue_thread_func (input=input@entry=0x1f90130) at ../mesa-18.3.5/src/util/u_queue.c:270
#5  0x00007ff95f623d37 in impl_thrd_routine (p=<optimized out>) at ../mesa-18.3.5/src/../include/c11/threads_posix.h:87
#6  0x00007ff98113d96a in start_thread (arg=0x7ff95f443700) at pthread_create.c:463
#7  0x00007ff983f261bf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 3 (Thread 0x7ff96b9d5700 (LWP 714)):
#0  0x00007ff983f1a5f3 in __GI___poll (fds=0x7ff960004a00, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007ff97de9e9c9 in g_main_context_poll (priority=<optimized out>, n_fds=1, fds=0x7ff960004a00, timeout=<optimized out>, context=0x7ff960000bf0) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gmain.c:4221
#2  g_main_context_iterate (context=context@entry=0x7ff960000bf0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gmain.c:3915
#3  0x00007ff97de9eadc in g_main_context_iteration (context=0x7ff960000bf0, may_block=may_block@entry=1) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gmain.c:3981
#4  0x00007ff98488bf7b in QEventDispatcherGlib::processEvents (this=0x7ff960000b20, flags=...) at kernel/qeventdispatcher_glib.cpp:424
#5  0x00007ff98483949b in QEventLoop::exec (this=this@entry=0x7ff96b9d4d00, flags=..., flags@entry=...) at ../../include/QtCore/../../src/corelib/global/qflags.h:140
#6  0x00007ff9846acb26 in QThread::exec (this=this@entry=0x1dd8f00) at ../../include/QtCore/../../src/corelib/global/qflags.h:120
#7  0x00007ff98837bbf5 in QQmlThreadPrivate::run (this=0x1dd8f00) at qml/ftw/qqmlthread.cpp:148
#8  0x00007ff9846add52 in QThreadPrivate::start (arg=0x1dd8f00) at thread/qthread_unix.cpp:361
#9  0x00007ff98113d96a in start_thread (arg=0x7ff96b9d5700) at pthread_create.c:463
#10 0x00007ff983f261bf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7ff971419700 (LWP 665)):
#0  0x00007ff983f15cf0 in __GI___libc_read (fd=7, buf=buf@entry=0x7ff971418ad0, nbytes=nbytes@entry=16) at ../sysdeps/unix/sysv/linux/read.c:27
#1  0x00007ff97dee4390 in read (__nbytes=16, __buf=0x7ff971418ad0, __fd=<optimized out>) at /usr/include/bits/unistd.h:44
#2  g_wakeup_acknowledge (wakeup=0x1d519b0) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gwakeup.c:210
#3  0x00007ff97de9e4b7 in g_main_context_check (context=context@entry=0x7ff964000bf0, max_priority=2147483647, fds=fds@entry=0x7ff964004db0, n_fds=n_fds@entry=1) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gmain.c:3698
#4  0x00007ff97de9e970 in g_main_context_iterate (context=context@entry=0x7ff964000bf0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gmain.c:3917
#5  0x00007ff97de9eadc in g_main_context_iteration (context=0x7ff964000bf0, may_block=may_block@entry=1) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gmain.c:3981
#6  0x00007ff98488bf7b in QEventDispatcherGlib::processEvents (this=0x7ff964000b20, flags=...) at kernel/qeventdispatcher_glib.cpp:424
#7  0x00007ff98483949b in QEventLoop::exec (this=this@entry=0x7ff971418cf0, flags=..., flags@entry=...) at ../../include/QtCore/../../src/corelib/global/qflags.h:140
#8  0x00007ff9846acb26 in QThread::exec (this=this@entry=0x7ff985ac2d80 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at ../../include/QtCore/../../src/corelib/global/qflags.h:120
#9  0x00007ff98584a495 in QDBusConnectionManager::run (this=0x7ff985ac2d80 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at qdbusconnection.cpp:178
#10 0x00007ff9846add52 in QThreadPrivate::start (arg=0x7ff985ac2d80 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at thread/qthread_unix.cpp:361
#11 0x00007ff98113d96a in start_thread (arg=0x7ff971419700) at pthread_create.c:463
#12 0x00007ff983f261bf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7ff98aa2d340 (LWP 616)):
[KCrash Handler]
#7  0x00007ff984874e26 in qNumVariantToHelper<int> (handlerManager=..., val=<error reading variable>, ok=0x7fff8f0c002f, d=...) at kernel/qvariant.cpp:3140
#8  QVariant::toInt (this=0x6e6f, ok=0x7fff8f0c002f) at kernel/qvariant.cpp:3140
#9  0x00007ff9693bc58a in TaskManager::VirtualDesktopInfo::XWindowPrivate::requestActivate (this=<optimized out>, desktop=...) at /var/tmp/portage/kde-plasma/plasma-workspace-5.15.3/work/plasma-workspace-5.15.3/libtaskmanager/virtualdesktopinfo.cpp:176
#10 0x00007ff94acb22e7 in PagerModel::changePage (this=<optimized out>, page=2) at /var/tmp/portage/kde-plasma/plasma-desktop-5.15.3/work/plasma-desktop-5.15.3/applets/pager/plugin/pagermodel.cpp:562
#11 0x00007ff94acb2ec4 in PagerModel::qt_metacall (this=0x3cd77f0, _c=QMetaObject::InvokeMetaMethod, _id=12, _a=0x7fff8f0c0210) at applets/pager/pagerplugin_autogen/include/moc_pagermodel.cpp:353
#12 0x00007ff988321c1d in QQmlObjectOrGadget::metacall (this=this@entry=0x7fff8f0c0550, type=type@entry=QMetaObject::InvokeMetaMethod, index=<optimized out>, index@entry=67, argv=<optimized out>) at ../../include/QtQml/5.12.2/QtQml/private/../../../../../src/qml/qml/ftw/qflagpointer_p.h:335
#13 0x00007ff98822a061 in CallMethod (object=..., index=<optimized out>, returnType=returnType@entry=43, argCount=<optimized out>, argTypes=<optimized out>, engine=engine@entry=0x1dd6c60, callArgs=<optimized out>, callType=<optimized out>) at jsruntime/qv4qobjectwrapper.cpp:1229
#14 0x00007ff98822b525 in CallPrecise (object=..., data=..., engine=engine@entry=0x1dd6c60, callArgs=callArgs@entry=0x7ff96ad965c0, callType=callType@entry=QMetaObject::InvokeMetaMethod) at ../../include/QtQml/5.12.2/QtQml/private/../../../../../src/qml/qml/qqmlpropertycache_p.h:214
#15 0x00007ff98822c186 in QV4::QObjectMethod::callInternal (this=<optimized out>, thisObject=0x7ff96ad96558, argv=<optimized out>, argc=<optimized out>) at jsruntime/qv4qobjectwrapper.cpp:2052
#16 0x00007ff9882b1865 in QV4::FunctionObject::call (argc=1, argv=0x7ff96ad96570, thisObject=0x7ff96ad96558, this=<optimized out>) at jsruntime/qv4functionobject_p.h:172
#17 QV4::Runtime::method_callProperty (engine=0x1dd6c60, base=<optimized out>, nameIndex=312, argv=0x7ff96ad96570, argc=<optimized out>) at jsruntime/qv4runtime.cpp:1391
#18 0x00007ff9882442c4 in QV4::Moth::VME::interpret (frame=0x7fff8f0c08c0, engine=0x1dd6c60, code=0x7ff95c0566f4 "\016\002") at jsruntime/qv4vme_moth.cpp:719
#19 0x00007ff988249057 in QV4::Moth::VME::exec (frame=frame@entry=0x7fff8f0c08c0, engine=engine@entry=0x1dd6c60) at jsruntime/qv4vme_moth.cpp:441
#20 0x00007ff9881dd85b in QV4::Function::call (this=this@entry=0x3cd43a0, thisObject=<optimized out>, argv=argv@entry=0x7ff96ad96500, argc=<optimized out>, context=<optimized out>) at jsruntime/qv4function.cpp:68
#21 0x00007ff98834a847 in QQmlJavaScriptExpression::evaluate (this=this@entry=0x3cdd5d0, callData=callData@entry=0x7ff96ad964d0, isUndefined=isUndefined@entry=0x0) at ../../include/QtQml/5.12.2/QtQml/private/../../../../../src/qml/jsruntime/qv4value_p.h:177
#22 0x00007ff9882ee6df in QQmlBoundSignalExpression::evaluate (this=<optimized out>, a=0x0) at ../../include/QtQml/5.12.2/QtQml/private/../../../../../src/qml/jsruntime/qv4jscall_p.h:95
#23 0x00007ff9882ef87b in QQmlBoundSignal_callback (e=0x3cddee0, a=0x0) at ../../include/QtQml/5.12.2/QtQml/private/../../../../../src/qml/qml/qqmlboundsignalexpressionpointer_p.h:69
#24 0x00007ff98832c303 in QQmlNotifier::emitNotify (endpoint=<optimized out>, a=a@entry=0x0) at qml/qqmlnotifier.cpp:104
#25 0x00007ff9882d14aa in QQmlData::signalEmitted (object=0x3cde920, index=3, a=0x0) at qml/qqmlengine.cpp:883
#26 0x00007ff984861c2f in QMetaObject::activate (sender=0x3cde920, signalOffset=<optimized out>, local_signal_index=<optimized out>, argv=0x0) at kernel/qobject.h:121
#27 0x00007ff9883cd9ba in QQmlTimer::event (this=0x3cde920, e=<optimized out>) at types/qqmltimer.cpp:340
#28 0x00007ff9860ac8f1 in QApplicationPrivate::notify_helper (this=this@entry=0x1cee330, receiver=receiver@entry=0x3cde920, e=e@entry=0x23fe320) at kernel/qapplication.cpp:3736
#29 0x00007ff9860b3f08 in QApplication::notify (this=0x7fff8f0c3310, receiver=0x3cde920, e=0x23fe320) at kernel/qapplication.cpp:3483
#30 0x00007ff98483a4c2 in QCoreApplication::notifyInternal2 (receiver=0x3cde920, event=0x23fe320) at kernel/qcoreapplication.cpp:1060
#31 0x00007ff98483d627 in QCoreApplicationPrivate::sendPostedEvents (receiver=0x0, event_type=0, data=0x1ce36b0) at kernel/qcoreapplication.cpp:1799
#32 0x00007ff98488c1c3 in postEventSourceDispatch (s=s@entry=0x1d3b630) at kernel/qeventdispatcher_glib.cpp:276
#33 0x00007ff97de9e817 in g_main_dispatch (context=0x7ff96c004ff0) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gmain.c:3182
#34 g_main_context_dispatch (context=context@entry=0x7ff96c004ff0) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gmain.c:3847
#35 0x00007ff97de9ea50 in g_main_context_iterate (context=context@entry=0x7ff96c004ff0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gmain.c:3920
#36 0x00007ff97de9eadc in g_main_context_iteration (context=0x7ff96c004ff0, may_block=may_block@entry=1) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gmain.c:3981
#37 0x00007ff98488bf63 in QEventDispatcherGlib::processEvents (this=0x1d4b770, flags=...) at kernel/qeventdispatcher_glib.cpp:422
#38 0x00007ff98483949b in QEventLoop::exec (this=this@entry=0xa7e9eb0, flags=..., flags@entry=...) at ../../include/QtCore/../../src/corelib/global/qflags.h:140
#39 0x00007ff984e26cc3 in QBasicDrag::drag (this=0x1d2a5b0, o=<optimized out>) at ../../include/QtCore/../../src/corelib/global/qflags.h:120
#40 0x00007ff984e24545 in QDragManager::drag (this=0xa953eb0, o=0xa801590) at kernel/qdnd.cpp:117
#41 0x00007ff984e247fb in QDrag::exec (this=0xa801590, supportedActions=..., defaultDropAction=<optimized out>) at kernel/qdrag.cpp:282
#42 0x00007ff94a89151e in DragHelper::startDragInternal (this=0x3c8b3b0, item=<optimized out>, mimeType=..., mimeData=..., url=..., icon=...) at /var/tmp/portage/kde-plasma/plasma-desktop-5.15.3/work/plasma-desktop-5.15.3/applets/taskmanager/plugin/draghelper.cpp:88
#43 0x00007ff984862e2a in QObject::event (this=0x3c8b3b0, e=<optimized out>) at kernel/qobject.cpp:1260
#44 0x00007ff9860ac8f1 in QApplicationPrivate::notify_helper (this=this@entry=0x1cee330, receiver=receiver@entry=0x3c8b3b0, e=e@entry=0x7ff96c015a50) at kernel/qapplication.cpp:3736
#45 0x00007ff9860b3f08 in QApplication::notify (this=0x7fff8f0c3310, receiver=0x3c8b3b0, e=0x7ff96c015a50) at kernel/qapplication.cpp:3483
#46 0x00007ff98483a4c2 in QCoreApplication::notifyInternal2 (receiver=0x3c8b3b0, event=0x7ff96c015a50) at kernel/qcoreapplication.cpp:1060
#47 0x00007ff98483d627 in QCoreApplicationPrivate::sendPostedEvents (receiver=0x0, event_type=0, data=0x1ce36b0) at kernel/qcoreapplication.cpp:1799
#48 0x00007ff98488c1c3 in postEventSourceDispatch (s=s@entry=0x1d3b630) at kernel/qeventdispatcher_glib.cpp:276
#49 0x00007ff97de9e817 in g_main_dispatch (context=0x7ff96c004ff0) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gmain.c:3182
#50 g_main_context_dispatch (context=context@entry=0x7ff96c004ff0) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gmain.c:3847
#51 0x00007ff97de9ea50 in g_main_context_iterate (context=context@entry=0x7ff96c004ff0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gmain.c:3920
#52 0x00007ff97de9eadc in g_main_context_iteration (context=0x7ff96c004ff0, may_block=may_block@entry=1) at /var/tmp/portage/dev-libs/glib-2.58.3/work/glib-2.58.3/glib/gmain.c:3981
#53 0x00007ff98488bf63 in QEventDispatcherGlib::processEvents (this=0x1d4b770, flags=...) at kernel/qeventdispatcher_glib.cpp:422
#54 0x00007ff98483949b in QEventLoop::exec (this=this@entry=0x7fff8f0c3210, flags=..., flags@entry=...) at ../../include/QtCore/../../src/corelib/global/qflags.h:140
#55 0x00007ff984841362 in QCoreApplication::exec () at ../../include/QtCore/../../src/corelib/global/qflags.h:120
#56 0x0000000000424e73 in main (argc=<optimized out>, argv=<optimized out>) at /var/tmp/portage/kde-plasma/plasma-workspace-5.15.3/work/plasma-workspace-5.15.3/shell/main.cpp:212
[Inferior 1 (process 616) detached]

Reported using DrKonqi

Comment 1 Eike Hein 2019-06-22 10:58:48 UTC

I can't reproduce this unortunately, does it still happen to you with 5.16.x?

Comment 2 Bug Janitor Service 2019-07-07 04:33:08 UTC

Dear Bug Submitter,

This bug has been in NEEDSINFO status with no change for at least
15 days. Please provide the requested information as soon as
possible and set the bug status as REPORTED. Due to regular bug
tracker maintenance, if the bug is still in NEEDSINFO status with
no change in 30 days the bug will be closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

If you have already provided the requested information, please
mark the bug as REPORTED so that the KDE team knows that the bug is
ready to be confirmed.

Thank you for helping us make KDE software even better for everyone!

Comment 3 Bug Janitor Service 2019-07-22 04:33:09 UTC

This bug has been in NEEDSINFO status with no change for at least
30 days. The bug is now closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

Thank you for helping us make KDE software even better for everyone!

Comment 4 Franz Trischberger 2019-09-21 06:59:27 UTC

Created attachment 122776 [details]
New crash information added by DrKonqi

plasmashell (5.16.5) using Qt 5.12.3

- What I was doing when the application crashed:

As in the OP moving a task from VT1 to VT2.
This is with most recent plasma-5.16.5.

-- Backtrace (Reduced):
#7  0x00007f50c0c3a766 in qNumVariantToHelper<int> (handlerManager=..., val=<error reading variable>, ok=0x7ffed5cc567f, d=...) at kernel/qvariant.cpp:3140
#8  0x00007f50c0c3a766 in QVariant::toInt(bool*) const (this=0x6e6f, ok=0x7ffed5cc567f) at kernel/qvariant.cpp:3140
#9  0x00007f50b808a1a7 in TaskManager::VirtualDesktopInfo::XWindowPrivate::requestActivate(QVariant const&) (this=<optimized out>, desktop=...) at /var/tmp/portage/kde-plasma/plasma-workspace-5.16.5/work/plasma-workspace-5.16.5/libtaskmanager/virtualdesktopinfo.cpp:172
#10 0x00007f50a8208987 in PagerModel::changePage(int) (this=<optimized out>, page=2) at /var/tmp/portage/kde-plasma/plasma-desktop-5.16.5/work/plasma-desktop-5.16.5/applets/pager/plugin/pagermodel.cpp:562
#11 0x00007f50a8209994 in PagerModel::qt_metacall(QMetaObject::Call, int, void**) (this=0x5184c30, _c=QMetaObject::InvokeMetaMethod, _id=12, _a=0x7ffed5cc5870) at applets/pager/pagerplugin_autogen/include/moc_pagermodel.cpp:353

Comment 5 Franz Trischberger 2020-01-02 16:01:54 UTC

Created attachment 124856 [details]
New crash information added by DrKonqi

plasmashell (5.17.4) using Qt 5.13.2

I am now at 5.17.4, this still happens
- What I was doing when the application crashed:

As before I tried to move a task to a different VT.
If you can't reproduce just hesitate before dropping.
It also crashes when you just hover the VT widget and slowly move the mouse, keeping the left mouse button pressed.

-- Backtrace (Reduced):
#7  0x00007fdc7cc8d416 in qNumVariantToHelper<int> (handlerManager=..., val=<error reading variable>, ok=0x7ffdeb7d82df, d=...) at kernel/qvariant.cpp:3140
#8  0x00007fdc7cc8d416 in QVariant::toInt(bool*) const (this=0x6e6f, ok=0x7ffdeb7d82df) at kernel/qvariant.cpp:3140
#9  0x00007fdc7516f2a7 in TaskManager::VirtualDesktopInfo::XWindowPrivate::requestActivate(QVariant const&) (this=<optimized out>, desktop=...) at /var/tmp/portage/kde-plasma/plasma-workspace-5.17.4-r1/work/plasma-workspace-5.17.4/libtaskmanager/virtualdesktopinfo.cpp:172
#10 0x00007fdc5e72cc17 in PagerModel::changePage(int) (this=<optimized out>, page=2) at /var/tmp/portage/kde-plasma/plasma-desktop-5.17.4-r1/work/plasma-desktop-5.17.4/applets/pager/plugin/pagermodel.cpp:566
#11 0x00007fdc5e72dc24 in PagerModel::qt_metacall(QMetaObject::Call, int, void**) (this=0x2a47d50, _c=QMetaObject::InvokeMetaMethod, _id=12, _a=0x7ffdeb7d84c0) at applets/pager/pagerplugin_autogen/include/moc_pagermodel.cpp:354

Comment 6 Franz Trischberger 2020-01-03 10:12:09 UTC

I finally looked at the source code, and found the issue!
The root lies in the indexing of QList vs. virtual desktops. lists get indexed starting from 0 while workspaces start from 1 (I am on X11).
The crash also doesn't happen in drag/dropping code but when the pager switches to the VD you hover with the LMB still pressed (which happens after a certain timeout).

I have 2 VDs configured.

Then look at this function:
void PagerModel::changePage(int page)
{
    if (currentPage() == page) {
        if (d->showDesktop) {
            QDBusConnection::sessionBus().asyncCall(QDBusMessage::createMethodCall(QLatin1String("org.kde.plasmashell"),
                QLatin1String("/PlasmaShell"),
                QLatin1String("org.kde.PlasmaShell"),
                QLatin1String("toggleDashboard")));
        }
    } else {
        if (d->pagerType == VirtualDesktops) {
            d->virtualDesktopInfo->requestActivate(d->virtualDesktopInfo->desktopIds().at(page)); /// here it crashes
        } else {
            const QStringList &runningActivities = d->activityInfo->runningActivities();
            if (page < runningActivities.length()) {
                KActivities::Controller activitiesController;
                activitiesController.setCurrentActivity(runningActivities.at(page));
            }
        }
    }
}

That function gets a page and directly hands it down to QVariantList in the marked line. From the callstack you can see that this function gets called with page == 2. desktopIds().at(2) is one off the end resulting in an invalid QVariant object.
I created a quick proof patch:

- d->virtualDesktopInfo->requestActivate(d->virtualDesktopInfo->desktopIds().at(page));
+ d->virtualDesktopInfo->requestActivate(d->virtualDesktopInfo->desktopIds().at(page-1));

which fixes the crash when moving a task to a different desktop, the task lands on the selected VD and the pager switches to it. Apperently changing VDs with a click on the pager is broken with this patch.

I do not know the codebase where all those dragging and clicking events get handled. But at least now the devs know how/where to fix it.

A quite tricky thing to handle is wayland. Here it looks like indices are 0-based (From the code handling is done with strings). With the patch applied dragging from VD1 to VD2 now doesn't switch but call showDesktop on VD1 (which is the active desktop)...

Comment 7 Christoph Feck 2020-01-21 09:46:45 UTC

If I understand comment 6 correctly, the issue is in the pager, not in the task manager, right?

Comment 8 Franz Trischberger 2020-01-21 10:38:45 UTC

Christoph, it looks like it's the Pager.
I just found out that the dragEnter event (and starting of the timer + changePage invocation with the bad index) is handled in a QML file "hidden" under the package structure. Likely the cause is there.

Comment 9 Kai Uwe Broulik 2020-01-21 10:40:12 UTC

Looks like Bug 415423 then, see https://cgit.kde.org/plasma-desktop.git/commit/?id=f5d1675a0dc1a1a0098eb5b1c727b5fe197e9930

Comment 10 Franz Trischberger 2020-01-21 11:17:03 UTC

Yes, that fixes the issue.
Please also close this issue: https://bugs.kde.org/show_bug.cgi?id=404909

Comment 11 Patrick Silva 2020-01-28 18:20:07 UTC


*** This bug has been marked as a duplicate of bug 415423 ***