Application: plasmashell (6.3.2) ApplicationNotResponding [ANR]: false Qt Version: 6.8.2 Frameworks Version: 6.11.0 Operating System: Linux 6.13.6-x64v3-xanmod1 x86_64 Windowing System: X11 Distribution: KDE neon 6.3 DrKonqi: 6.3.2 [CoredumpBackend] -- Information about the crash: Plasma crashes when I drag any widget to the panel. This happens with any widget (both 1st-party and 3rd-party), on any panel. The crash can be reproduced every time. -- Backtrace (Reduced): #6 __pthread_kill_implementation (no_tid=0, signo=6, threadid=<optimized out>) at ./nptl/pthread_kill.c:44 #7 __pthread_kill_internal (signo=6, threadid=<optimized out>) at ./nptl/pthread_kill.c:78 #8 __GI___pthread_kill (threadid=<optimized out>, signo=signo@entry=6) at ./nptl/pthread_kill.c:89 #9 0x00007f482804527e in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26 #10 0x00007f48280288ff in __GI_abort () at ./stdlib/abort.c:79 Reported using DrKonqi
Created attachment 179258 [details] New crash information added by DrKonqi DrKonqi auto-attaching complete backtrace.
Thank you for the bug report. I'm not able to reproduce this on git-master. Unfortunately the backtrace is incomplete and missing debug symbols for the following lines that we need to figure out exactly what's going wrong: #11 0x00007f4828d0c1ac in ??? () at /lib/x86_64-linux-gnu/libQt6Core.so.6 #18 0x00007f4829ca07fa in ??? () at /lib/x86_64-linux-gnu/libQt6Qml.so.6 Could you please install debug symbols and attach a new symbolicated backtrace generated by using coredumpctl gdb in a terminal window? See https://community.kde.org/Guidelines_and_HOWTOs/Debugging/How_to_create_useful_crash_reports#Retrieving_a_backtrace_using_coredumpctl for details about how to do this. Thanks again!
(In reply to TraceyC from comment #2) > Thank you for the bug report. I'm not able to reproduce this on git-master. > Unfortunately the backtrace is incomplete and missing debug symbols for the > following lines that we need to figure out exactly what's going wrong: > > #11 0x00007f4828d0c1ac in ??? () at /lib/x86_64-linux-gnu/libQt6Core.so.6 > #18 0x00007f4829ca07fa in ??? () at /lib/x86_64-linux-gnu/libQt6Qml.so.6 > > Could you please install debug symbols and attach a new symbolicated > backtrace generated by using coredumpctl gdb in a terminal window? See > https://community.kde.org/Guidelines_and_HOWTOs/Debugging/ > How_to_create_useful_crash_reports#Retrieving_a_backtrace_using_coredumpctl > for details about how to do this. Thanks again! What debug symbols should I install? The automatic installer doesn't work (see bug 501338) and I can't find a "libqt6core-dbgsym" or a "libqt6qml-dbgsym" package on Neon, so I don't know which one I should install.
(In reply to Riccardo Robecchi from comment #3) > What debug symbols should I install? The automatic installer doesn't work > (see bug 501338) Bummer. Thanks for reporting it, I saw there's an older report with the same backtrace. Hopefully there will be some movement on it now. > and I can't find a "libqt6core-dbgsym" or a > "libqt6qml-dbgsym" package on Neon, so I don't know which one I should > install. libQt6Core.so comes from qt6-base, so searching apt for this should show you everything that needs to be installed for that: apt search qt6-base | grep dbg libQt6Qml.so comes from qt6-declarative, so a similar search should get you the packages for that.
Created attachment 179345 [details] crash dump I installed the symbols for both qt6-base and qt6-declarative. Here is the crash dump, I hope it proves more useful. Let me know if you need anything else.
Thanks for the updated backtrace. It is indeed more useful. Pasting here for searchability Message: Process 1010690 (plasmashell) of user 1000 dumped core. Module libkvantum.so from deb qt6-style-kvantum-1.1.3-0ubuntu1~oracular1.amd64 Module libgomp.so.1 from deb gcc-14-14.2.0-4ubuntu2~24.04.amd64 Module libzstd.so.1 from deb libzstd-1.5.5+dfsg2-2build1.1.amd64 Module libsystemd.so.0 from deb systemd-255.4-1ubuntu8.5.amd64 Module libudev.so.1 from deb systemd-255.4-1ubuntu8.5.amd64 Module libgcc_s.so.1 from deb gcc-14-14.2.0-4ubuntu2~24.04.amd64 Module libstdc++.so.6 from deb gcc-14-14.2.0-4ubuntu2~24.04.amd64 Stack trace of thread 1010690: #0 0x00007f037a247557 _ZNK17QQuickItemPrivate21itemToParentTransformEP10QTransform (libQt6Quick.so.6 + 0x647557) #1 0x00007f037a24764a _ZNK17QQuickItemPrivate21itemToWindowTransformEv (libQt6Quick.so.6 + 0x64764a) #2 0x00007f037a24ff01 _ZNK10QQuickItem10mapToSceneERK7QPointF (libQt6Quick.so.6 + 0x64ff01) #3 0x00007f037b1c1cd3 n/a (libPlasmaQuick.so.6 + 0x40cd3) #4 0x00007f037b1ca4c1 _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x494c1) #5 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #6 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #7 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #8 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #9 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #10 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #11 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #12 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #13 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #14 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #15 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #16 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #17 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #18 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #19 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #20 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #21 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #22 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #23 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #24 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #25 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #26 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #27 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #28 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #29 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #30 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #31 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #32 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #33 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #34 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #35 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #36 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #37 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #38 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #39 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #40 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #41 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #42 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #43 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #44 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #45 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #46 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #47 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #48 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #49 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #50 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #51 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #52 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #53 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #54 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #55 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #56 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #57 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #58 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #59 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #60 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0) #61 0x00007f037b1caa5a _ZN11PlasmaQuick6Dialog5eventEP6QEvent (libPlasmaQuick.so.6 + 0x49a5a) #62 0x00007f037ac01158 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt6Widgets.so.6 + 0x601158) #63 0x00007f03788aefa0 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x4aefa0)
Sentry managed to get a few more symbols in the backtrace; see the "Sentry Crash Report" field. Here are the important parts: KPackage::PackagePrivate::isInsidePackageDir (package.cpp:267) KPackage::Package::filePath (package.cpp:359) KPackage::Package::isValid (package.cpp:93) I still can't see where in Plasmashell it's accessing these from though; those parts are still missing. Can you be very specific about how exactly you're triggering the issue? I can't make it happen after a few tries on my Fedora 41 + git master KDE stuff system, but there are multiple ways to drag things, and multiple modes involved.
(In reply to Nate Graham from comment #7) > Can you be very specific about how exactly you're triggering the issue? I > can't make it happen after a few tries on my Fedora 41 + git master KDE > stuff system, but there are multiple ways to drag things, and multiple modes > involved. I'll try! - right click on the desktop and select "enter edit mode" - click on "add or manage widgets" - click and hold on a widget from the list (e.g. analogue clock) and drag it to the panel. Plasma crashes as soon as the widget touches the panel, I don't even have to release the click. Does this help?
Yeah no crash here with those steps. Works as expected for me, at least on Wayland on Fedora 41 KDE. Might be X11-specific, or might be a neon packaging issue, or might be something else.
For what it's worth, following those steps, I am unable to reproduce on X11 on either Neon User or Neon Testing
I've just spent half the weekend updating Neon to the 24.04 base on my desktop. The bug is reproducible there, too. Considering in both cases the issue appears after updating from 5.27.10, maybe it is related to old, incompatible widgets leaving something in the configuration?
Could be. Can you still reproduce this in Plasma 6.4.4 or later?
🐛🧹 ⚠️ This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information, then set the bug status to REPORTED. If there is no change for at least 30 days, it will be automatically closed as RESOLVED WORKSFORME. For more information about our bug triaging procedures, please read https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging. Thank you for helping us make KDE software even better for everyone!
I've just tried and yes, it still happens. Now Plasma just crashes without restarting, and I don't get the "oops, Plasma crashed" dialogue any more though!
Hmm, that's probably something different. If it doesn't restart, that means it didn't crash, it exited. So it sounds like this issue is in fact resolved, but unfortunately has been replaced with a worse one! Can I ask you to open a new bug report about it? I imagine plasmashell won't show up in the output of `coredumpctl --reverse`; if that's the case, please grab a journal log (`journalctl --follow --unit plasma-plasmashell.service`) that includes the time of the issue. Thanks!
Plasmashell actually does come up in 'coredumptctl --reverse', so I guess it is still crashing after all, it's just that for some reason it doesn't restart and drkonqi does not intervene.
Created attachment 184531 [details] Log around the time of the crash Here is what appears in journalctl. Drkonqi seems not to be able to find the crash data and that's why it doesn't do anything. Let me know if I should still open a new bug or if this can be reopened. Thanks!
Thanks for the follow up. Since there's a coredump, that does indicate a crash. Can you please attach a backtrace of the crash using the coredumpctl command-line program, as detailed in https://community.kde.org/Guidelines_and_HOWTOs/Debugging/How_to_create_useful_crash_reports#Retrieving_a_backtrace_using_coredumpctl ? Thanks.
Created attachment 184559 [details] Backtrace Here is the backtrace. It looks like there is an issue with a loop, as gdb went on for hours and I didn't realise it was because it was printing always the same three things over and over again without getting anywhere. I stopped after getting to line 10562, which was identical to those you can read here except for error/event code.
Thanks for the new backtrace. It does look the same as the older one. The loop would explain why plasmashell never restarts. Pasting the gdb backtrace. Core was generated by `/usr/bin/plasmashell'. Program terminated with signal SIGSEGV, Segmentation fault. #0 0x00007f5a7986a657 in QQuickItemPrivate::itemToParentTransform (this=this@entry=0x557c4654bd80, t=t@entry=0x7ffe310cc120) at /usr/src/qt6-declarative-6.9.1-0zneon+24.04+noble+release+build58/src/quick/items/qquickitem.cpp:3207 warning: 3207 /usr/src/qt6-declarative-6.9.1-0zneon+24.04+noble+release+build58/src/quick/items/qquickitem.cpp: No such file or directory [Current thread is 1 (Thread 0x7f5a716a9d00 (LWP 484972))] #0 0x00007f5a7986a657 in QQuickItemPrivate::itemToParentTransform (this=this@entry=0x557c4654bd80, t=t@entry=0x7ffe310cc120) at /usr/src/qt6-declarative-6.9.1-0zneon+24.04+noble+release+build58/src/quick/items/qquickitem.cpp:3207 #1 0x00007f5a7986a74a in QQuickItemPrivate::itemToWindowTransform (this=0x557c4654bd80) at /usr/src/qt6-declarative-6.9.1-0zneon+24.04+noble+release+build58/src/quick/items/qquickitem.cpp:3188 #2 0x00007f5a7987b761 in QQuickItem::mapToScene (this=<optimised out>, point=...) at /usr/src/qt6-declarative-6.9.1-0zneon+24.04+noble+release+build58/src/quick/items/qquickitem.cpp:8872 #3 0x00007f5a7a72e757 in ??? () at /lib/x86_64-linux-gnu/libPlasmaQuick.so.6 #4 0x00007f5a7a737169 in PlasmaQuick::Dialog::event(QEvent*) () at /lib/x86_64-linux-gnu/libPlasmaQuick.so.6 #5 0x00007f5a7a23e21d in QApplicationPrivate::notify_helper (this=<optimised out>, receiver=0x557c45ebad00, e=0x7ffe310cc510) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/widgets/kernel/qapplication.cpp:3303 #6 0x00007f5a77eb6340 in QCoreApplication::notifyInternal2 (receiver=0x557c45ebad00, event=0x7ffe310cc510) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/corelib/kernel/qcoreapplication.cpp:1106 #7 0x00007f5a7a7376a5 in PlasmaQuick::Dialog::event(QEvent*) () at /lib/x86_64-linux-gnu/libPlasmaQuick.so.6 #8 0x00007f5a7a23e21d in QApplicationPrivate::notify_helper (this=<optimised out>, receiver=0x557c45ebad00, e=0x7ffe310cc730) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/widgets/kernel/qapplication.cpp:3303 #9 0x00007f5a77eb6340 in QCoreApplication::notifyInternal2 (receiver=0x557c45ebad00, event=0x7ffe310cc730) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/corelib/kernel/qcoreapplication.cpp:1106 #10 0x00007f5a7a7376a5 in PlasmaQuick::Dialog::event(QEvent*) () at /lib/x86_64-linux-gnu/libPlasmaQuick.so.6 #11 0x00007f5a7a23e21d in QApplicationPrivate::notify_helper (this=<optimised out>, receiver=0x557c45ebad00, e=0x7ffe310cc950) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/widgets/kernel/qapplication.cpp:3303 #12 0x00007f5a77eb6340 in QCoreApplication::notifyInternal2 (receiver=0x557c45ebad00, event=0x7ffe310cc950) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/corelib/kernel/qcoreapplication.cpp:1106 #13 0x00007f5a7a7376a5 in PlasmaQuick::Dialog::event(QEvent*) () at /lib/x86_64-linux-gnu/libPlasmaQuick.so.6 #14 0x00007f5a7a23e21d in QApplicationPrivate::notify_helper (this=<optimised out>, receiver=0x557c45ebad00, e=0x7ffe310ccb70) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/widgets/kernel/qapplication.cpp:3303 #15 0x00007f5a77eb6340 in QCoreApplication::notifyInternal2 (receiver=0x557c45ebad00, event=0x7ffe310ccb70) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/corelib/kernel/qcoreapplication.cpp:1106 #16 0x00007f5a7a7376a5 in PlasmaQuick::Dialog::event(QEvent*) () at /lib/x86_64-linux-gnu/libPlasmaQuick.so.6 #17 0x00007f5a7a23e21d in QApplicationPrivate::notify_helper (this=<optimised out>, receiver=0x557c45ebad00, e=0x7ffe310ccd90) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/widgets/kernel/qapplication.cpp:3303 #18 0x00007f5a77eb6340 in QCoreApplication::notifyInternal2 (receiver=0x557c45ebad00, event=0x7ffe310ccd90) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/corelib/kernel/qcoreapplication.cpp:1106 #19 0x00007f5a7a7376a5 in PlasmaQuick::Dialog::event(QEvent*) () at /lib/x86_64-linux-gnu/libPlasmaQuick.so.6 #20 0x00007f5a7a23e21d in QApplicationPrivate::notify_helper (this=<optimised out>, receiver=0x557c45ebad00, e=0x7ffe310ccfb0) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/widgets/kernel/qapplication.cpp:3303 #21 0x00007f5a77eb6340 in QCoreApplication::notifyInternal2 (receiver=0x557c45ebad00, event=0x7ffe310ccfb0) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/corelib/kernel/qcoreapplication.cpp:1106 #22 0x00007f5a7a7376a5 in PlasmaQuick::Dialog::event(QEvent*) () at /lib/x86_64-linux-gnu/libPlasmaQuick.so.6 #23 0x00007f5a7a23e21d in QApplicationPrivate::notify_helper (this=<optimised out>, receiver=0x557c45ebad00, e=0x7ffe310cd1d0) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/widgets/kernel/qapplication.cpp:3303 #24 0x00007f5a77eb6340 in QCoreApplication::notifyInternal2 (receiver=0x557c45ebad00, event=0x7ffe310cd1d0) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/corelib/kernel/qcoreapplication.cpp:1106 #25 0x00007f5a7a7376a5 in PlasmaQuick::Dialog::event(QEvent*) () at /lib/x86_64-linux-gnu/libPlasmaQuick.so.6 #26 0x00007f5a7a23e21d in QApplicationPrivate::notify_helper (this=<optimised out>, receiver=0x557c45ebad00, e=0x7ffe310cd3f0) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/widgets/kernel/qapplication.cpp:3303 #27 0x00007f5a77eb6340 in QCoreApplication::notifyInternal2 (receiver=0x557c45ebad00, event=0x7ffe310cd3f0) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/corelib/kernel/qcoreapplication.cpp:1106 #28 0x00007f5a7a7376a5 in PlasmaQuick::Dialog::event(QEvent*) () at /lib/x86_64-linux-gnu/libPlasmaQuick.so.6 #29 0x00007f5a7a23e21d in QApplicationPrivate::notify_helper (this=<optimised out>, receiver=0x557c45ebad00, e=0x7ffe310cd610) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/widgets/kernel/qapplication.cpp:3303 #30 0x00007f5a77eb6340 in QCoreApplication::notifyInternal2 (receiver=0x557c45ebad00, event=0x7ffe310cd610) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/corelib/kernel/qcoreapplication.cpp:1106 #31 0x00007f5a7a7376a5 in PlasmaQuick::Dialog::event(QEvent*) () at /lib/x86_64-linux-gnu/libPlasmaQuick.so.6 #32 0x00007f5a7a23e21d in QApplicationPrivate::notify_helper (this=<optimised out>, receiver=0x557c45ebad00, e=0x7ffe310cd830) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/widgets/kernel/qapplication.cpp:3303 #33 0x00007f5a77eb6340 in QCoreApplication::notifyInternal2 (receiver=0x557c45ebad00, event=0x7ffe310cd830) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/corelib/kernel/qcoreapplication.cpp:1106 #34 0x00007f5a7a7376a5 in PlasmaQuick::Dialog::event(QEvent*) () at /lib/x86_64-linux-gnu/libPlasmaQuick.so.6 #35 0x00007f5a7a23e21d in QApplicationPrivate::notify_helper (this=<optimised out>, receiver=0x557c45ebad00, e=0x7ffe310cda50) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/widgets/kernel/qapplication.cpp:3303 #36 0x00007f5a77eb6340 in QCoreApplication::notifyInternal2 (receiver=0x557c45ebad00, event=0x7ffe310cda50) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/corelib/kernel/qcoreapplication.cpp:1106 #37 0x00007f5a7a7376a5 in PlasmaQuick::Dialog::event(QEvent*) () at /lib/x86_64-linux-gnu/libPlasmaQuick.so.6 #38 0x00007f5a7a23e21d in QApplicationPrivate::notify_helper (this=<optimised out>, receiver=0x557c45ebad00, e=0x7ffe310cdc70) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/widgets/kernel/qapplication.cpp:3303 #39 0x00007f5a77eb6340 in QCoreApplication::notifyInternal2 (receiver=0x557c45ebad00, event=0x7ffe310cdc70) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/corelib/kernel/qcoreapplication.cpp:1106 #40 0x00007f5a7a7376a5 in PlasmaQuick::Dialog::event(QEvent*) () at /lib/x86_64-linux-gnu/libPlasmaQuick.so.6 #41 0x00007f5a7a23e21d in QApplicationPrivate::notify_helper (this=<optimised out>, receiver=0x557c45ebad00, e=0x7ffe310cde90) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/widgets/kernel/qapplication.cpp:3303 #42 0x00007f5a77eb6340 in QCoreApplication::notifyInternal2 (receiver=0x557c45ebad00, event=0x7ffe310cde90) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/corelib/kernel/qcoreapplication.cpp:1106 #43 0x00007f5a7a7376a5 in PlasmaQuick::Dialog::event(QEvent*) () at /lib/x86_64-linux-gnu/libPlasmaQuick.so.6 #44 0x00007f5a7a23e21d in QApplicationPrivate::notify_helper (this=<optimised out>, receiver=0x557c45ebad00, e=0x7ffe310ce0b0) at /usr/src/qt6-base-6.9.1-0zneon+24.04+noble+release+build118/src/widgets/kernel/qapplication.cpp:3303
I think I get the same crash with Plasma 6.7.4. Reproducible crash when trying to drag a widget (e.g. a launcher) to the panel. Happens every time.
I found another report with the same crash, it looks like this has been fixed in Plasma 6.4. (In reply to Bernd Steinhauser from comment #21) > I think I get the same crash with Plasma 6.7.4. Different crashes might have different causes, even if the symptoms look similar. To determine if you're affected by the same cause, we need more information. Can you please attach a backtrace of the crash using the `coredumpctl` command-line program, as detailed in https://community.kde.org/Guidelines_and_HOWTOs/Debugging/How_to_create_useful_crash_reports#Retrieving_a_backtrace_using_coredumpctl? Thanks!
Ok, I did some investigating with Claude Opus 5 and was able to find the root cause of the crash. Here's a brief summary of what happens: Dialog::event() tests the drag position against the main item in QPointF space, but sends the corrected position back to itself as an integer QPoint. When the item rect has fractional edges, the rounding undoes the clamp, so the corrected point equals the original, the containment test fails again, and the event is re-sent forever. plasmashell dies of stack exhaustion after ~17,400 iterations. From the core: main item y=9.9999895, height=1146.0000005 → bottom=1155.99999; tested point y=1156. qBound() returned 1155.99999, toPoint() rounded it back to 1156. The fractional edges are floating point error in the background margins and item size, not display scaling — reproduced with all outputs at 100%. Clamping to integer bounds inside the rect fixes it; tested locally on 6.7.4, no longer crashes. I'll attach the backtrace and two patches as suggested by Claude. I tested with those applied and it no longer crashes, I can add a widget (e.g. a launcher) to the taskbar. The first patch implements the ceil/floor to round to the next integer, which fixes the actual problem. The second patch isn't strictly necessary to fix this bug, but it should prevent the endless loop if a similar problem came up.
Created attachment 195366 [details] backtrace of the crash
Created attachment 195367 [details] Patch 1: Fix infinite recursion in Dialog::event() during drag and drop
Created attachment 195368 [details] Patch 2: Don't re-send drag events when the position correction makes no progress
(In reply to Bernd Steinhauser from comment #25) > Created attachment 195367 [details] > Patch 1: Fix infinite recursion in Dialog::event() during drag and drop Thanks for the patches! The next step is to create a merge request. In the MR, please add BUG: [the number of this Bugzilla ticket] so it gets linked to this report. https://community.kde.org/Infrastructure/GitLab#Submitting_a_merge_request If you want to discuss the development work, please reach out in our Matrix channel for new contributors https://community.kde.org/Get_Involved#New_Contributor?_Say_Hello_In_Matrix Thanks again!
Bernd, can you confirm building with those patches fixes the issue? If so please move the status when you reply to CONFIRMED. Then you can submit the patches to KDE's GitLab where all the code lives: https://invent.kde.org. Thanks for working on the patches!
I'll try to get it done in the next few days.
Please set to CONFIRMED if you confirm building with those patches fixes the issue. Thanks.
(In reply to Bernd Steinhauser from comment #23) > I tested with those applied and it no longer crashes, I can add a widget (e.g. a > launcher) to the taskbar. The first patch implements the ceil/floor to round > to the next integer, which fixes the actual problem. The second patch isn't > strictly necessary to fix this bug, but it should prevent the endless loop > if a similar problem came up. I already did that two weeks ago?
My apologies.
A possibly relevant merge request was started @ https://invent.kde.org/plasma/libplasma/-/merge_requests/1579
A possibly relevant merge request was started @ https://invent.kde.org/plasma/libplasma/-/merge_requests/1590
Git commit 974328550ccb41cba9ccd8b0cd78cb9870b6f64d by Nate Graham, on behalf of David Edmundson. Committed on 29/09/2026 at 21:40. Pushed by ngraham into branch 'master'. EdgeEventForwarder: Avoid potential recursion Qt < 6.12 doesn't support floating point precision for drag events. This leads to a possibility that when we round we end up with an event back at our window that is outside the main window and we need to send it again. Rather than trying to guard this specific situation, make edge event forwarding only affect real events not synthesised events. M +6 -0 src/plasmaquick/dialog.cpp M +6 -0 src/plasmaquick/edgeeventforwarder.cpp https://invent.kde.org/plasma/libplasma/-/commit/974328550ccb41cba9ccd8b0cd78cb9870b6f64d
Git commit 6d42032d46347d154796e0b4b59d00408bf427dd by Nate Graham. Committed on 30/09/2026 at 00:47. Pushed by ngraham into branch 'Plasma/6.8'. EdgeEventForwarder: Avoid potential recursion Qt < 6.12 doesn't support floating point precision for drag events. This leads to a possibility that when we round we end up with an event back at our window that is outside the main window and we need to send it again. Rather than trying to guard this specific situation, make edge event forwarding only affect real events not synthesised events. (cherry picked from commit 72fe8f12534edd6d7f9658ad61df4f2de228360c) Co-authored-by: David Edmundson <kde@davidedmundson.co.uk> M +6 -0 src/plasmaquick/dialog.cpp M +6 -0 src/plasmaquick/edgeeventforwarder.cpp https://invent.kde.org/plasma/libplasma/-/commit/6d42032d46347d154796e0b4b59d00408bf427dd
Git commit 032c5dfc47698a8a05194b594e5a83aba8b51046 by Nate Graham. Committed on 30/09/2026 at 00:48. Pushed by ngraham into branch 'Plasma/6.7'. EdgeEventForwarder: Avoid potential recursion Qt < 6.12 doesn't support floating point precision for drag events. This leads to a possibility that when we round we end up with an event back at our window that is outside the main window and we need to send it again. Rather than trying to guard this specific situation, make edge event forwarding only affect real events not synthesised events. (cherry picked from commit 72fe8f12534edd6d7f9658ad61df4f2de228360c) Co-authored-by: David Edmundson <kde@davidedmundson.co.uk> M +6 -0 src/plasmaquick/dialog.cpp M +6 -0 src/plasmaquick/edgeeventforwarder.cpp https://invent.kde.org/plasma/libplasma/-/commit/032c5dfc47698a8a05194b594e5a83aba8b51046