Why everytime Plasma shell crashes, I get a useless backtrace?

Every now and then I get a spontaneous crash in Plasma shell, and when Dr. Konqi comes up I get this back trace report:

(its in the middle of the thing - but it doesn’t get better anywhere - all threads are either full of question marks or just “cannot access memory”)

What’s going on? How can I get this to be useful? I have installed plasma-workspace-dbgsym but that doesn’t seem to make any improvements, but also - even without a debug symbols package the backtrace should list the binary files and should not have “cannot access memory” bits.

BTW - I’m running Plasma 6 on Wayland from Neon testing.

Click on install debug symbols and regenerate the backtrace to make it useful. Then report it to bugzilla.

The debug symbols are already installed (as I mentioned above). If I click the “Install Debug Symbols” icon I get the Debug Symbol Installer window with a rotating gear and then nothing happens - I left it running for half an hour and it didn’t go anywhere. If I try to report this crash I get “the crash data isn’t useful” message (or some such).

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I tried to find the old crash and opened drkonqi-coredump-gui and that shows something that looks useful. With the interactive debugger I got this:

#0  0x00007f1b5ad564c0 in KCrash::defaultCrashHandler(int) () at /lib/x86_64-linux-gnu/libKF6Crash.so.6
#1  0x00007f1b57c42520 in <signal handler called> () at /lib/x86_64-linux-gnu/libc.so.6
#2  0x00007f1b5adf1f1b in wl_proxy_marshal_flags () at /lib/x86_64-linux-gnu/libwayland-client.so.0
#3  0x00007f1b500c5e8e in xdg_activation_token_v1_set_app_id (app_id=0x55a13d366200 " \272\027[\033\177", xdg_activation_token_v1=0x55a13b5b7c50) at ./obj-x86_64-linux-gnu/src/platforms/wayland/wayland-xdg-activation-v1-client-protocol.h:363
#4  QtWayland::org_kde_kwin_shadow_manager::unset(wl_surface*) (this=<optimized out>, this=<optimized out>, surface=0x55a13d366200) at ./obj-x86_64-linux-gnu/src/platforms/wayland/qwayland-shadow.cpp:78
#5  WindowShadow::internalDestroy() (this=0x55a13d367d90) at ./src/platforms/wayland/windowshadow.cpp:195
#6  0x00007f1b5ab8851a in KWindowShadow::destroy() (this=this@entry=0x55a13d387550) at ./src/kwindowshadow.cpp:266
#7  0x00007f1b5ab8853b in KWindowShadow::~KWindowShadow() (this=0x55a13d387550, this=<optimized out>) at ./src/kwindowshadow.cpp:65
#8  0x00007f1b5ab8856d in KWindowShadow::~KWindowShadow() (this=0x55a13d387550, this=<optimized out>) at ./src/kwindowshadow.cpp:66
#9  0x00007f1b587ca0aa in QObjectPrivate::deleteChildren() (this=this@entry=0x55a13d351b80) at ./src/corelib/kernel/qobject.cpp:2207
#10 0x00007f1b587cdfb8 in QObject::~QObject() (this=<optimized out>, this=<optimized out>) at ./src/corelib/kernel/qobject.cpp:1159
#11 0x00007f1b5b126c9d in DialogShadows::~DialogShadows() (this=0x55a13d37e8e0, this=<optimized out>) at ./src/plasmaquick/dialogshadows.cpp:63
#12 0x00007f1b587ca0aa in QObjectPrivate::deleteChildren() (this=this@entry=0x55a13b56c2f0) at ./src/corelib/kernel/qobject.cpp:2207
#13 0x00007f1b587cdfb8 in QObject::~QObject() (this=<optimized out>, this=<optimized out>) at ./src/corelib/kernel/qobject.cpp:1159
#14 0x000055a13b3f5ab3 in main(int, char**) (argc=<optimized out>, argv=<optimized out>) at ./shell/main.cpp:215

so I opened a bug with this trace. I’m not 100% sure I’m looking at the same thing for which the Dr Konqi wizard was useless about, but 99% sure.

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You only said that you install a useless package. Actual debug symbols are installed by debuginfod and they are installed AFTER you click on install debug symbols. Dunno why you get a rotating gear in the installer, probably a neon packaging issue. In Fedora you don’t even have that installer unless you use drkonqi from my copr.

@hazel-bunny, debuginfo packages aren’t installed by debuginfod. debuginfod downloads .sos for the specific debug operation, and these are cached by gdb. debuginfo packages are provided by the package manager.

@guss77, for future reference, the “interactive debugger” (coredumpctl debug, which usually corresponds to --debugger=gdb, by default) aforereferenced displays the packages that you need to install with a simple command to run (although this occasionally requires that you prepend sudo, which shall be obvious at the time). This means that you needn’t rely upon Dr Konqi’s (unreliable) GUI for this.

It’ll be. If Dr Konqi caught it, coredumpctl shall have, which is what drkonqi-coredump-gui polls from upon invocation.