Can you attach a backtrace from one of the crash reports? The fact that something is crashing over and over again is obviously a problem, but we need to know the details so we can fix it. :)

See https://community.kde.org/Get_Involved/Issue_Reporting#Crash_reports_must_include_backtraces

(In reply to Nate Graham from comment #1)
> Can you attach a backtrace from one of the crash reports? The fact that
> something is crashing over and over again is obviously a problem, but we
> need to know the details so we can fix it. :)
> 
> See
> https://community.kde.org/Get_Involved/
> Issue_Reporting#Crash_reports_must_include_backtraces

TO be honest, i have no idea how to do that. I'll need a bit of instruction if someone has the time or written instructions to follow. They only seem to be created as a result of or during the logout/login process.  I do not get any chance to create a backtrace via drkonqi as that never appears and its also subject to coredumping.

You can use gdb on a coredump file to get the backtrace. For details, Hopefully, you didn't remove the all yet, and the binaries are still the same.

For details, see e.g. https://stackoverflow.com/questions/5745215/getting-stacktrace-from-core-dump

(In reply to Christoph Feck from comment #3)
> You can use gdb on a coredump file to get the backtrace. For details,
> Hopefully, you didn't remove the all yet, and the binaries are still the
> same.
> 
> For details, see e.g.
> https://stackoverflow.com/questions/5745215/getting-stacktrace-from-core-dump

Thanks for that.  I kept all of them just in case.  I'll do the first plasmashell coredump and post that.

Created attachment 130366 [details]
backtrace file

Full backtrace

Created attachment 130367 [details]
backtrace file plasmashell 1

backtrace file plasmashell 1

Created attachment 130368 [details]
backtrace file plasmashell 2

backtrace file plasmashell 2

I've added 3 backtrace (full) files for the following files:
gdb-drkonqi-backtrace-full
gdb-plasmashell-3058-backtrace-full
gdb-plasmashell-1548-backtrace-full

They are for the following files i will attach these if you request them (in lz4 format), they are in creation time order
3817472  core.drkonqi.1002.b249b78ca7c8444f83be0aff12e3c849.3059.1595156511000000000000
4726784  core.plasmashell.1002.b249b78ca7c8444f83be0aff12e3c849.3058.1595156511000000000000
482148352 core.plasmashell.1002.b249b78ca7c8444f83be0aff12e3c849.1548.1595156514000000000000

They all relate to the first logout only.

The backtrace files all displayed these few lines but i didn't know what to do about it.
warning: Ignoring non-absolute filename: <linux-vdso.so.1>
Missing separate debuginfo for linux-vdso.so.1
Try: zypper install -C "debuginfo(build-id)=f4493ee3352f494cabebd179165698eb38cd5c5c"

Thanks. The backtraces are beyond my ability to interpret, so I'll hand it off to other more experience devs at this point.

(In reply to Nate Graham from comment #9)
> Thanks. The backtraces are beyond my ability to interpret, so I'll hand it
> off to other more experience devs at this point.

Thanks.
I'd like to add that these three appear after a logout and before a login, i originally thought a login also created these coredumps.  The login might create the other coredumps like kglobalaccel5  kded5 etc but I'll log those later with backtraces and link them to this bug report

FWIW I'm also seeing kglobalaccel crashing in a loop. See Bug 424931.

Actually the backtrace in my bug looks identical to yours!

*** Bug 424931 has been marked as a duplicate of this bug. ***

I'm able to reproduce the same crash here in my everything-built-from-source plasma session. I am seeing crashes in kglobalaccel and kactivitymanagerd. All of the crashes have the same backtrace as the ones for BingmyBong's plasmashell crashes:

#0  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
#1  0x00007f4fb2d26539 in __GI_abort () at abort.c:79
#2  0x00007f4fb2f68c27 in qt_message_fatal (message=<synthetic pointer>..., context=...) at global/qlogging.cpp:1914
#3  QMessageLogger::fatal (this=this@entry=0x7ffd8da2e2b0, msg=msg@entry=0x7f4fb3a82f05 "%s") at global/qlogging.cpp:893
#4  0x00007f4fb35b96d4 in init_platform (argv=<optimized out>, argc=@0x7ffd8da2e4fc: 1, platformThemeName=..., platformPluginPath=..., 
    pluginNamesWithArguments=...) at ../../include/QtCore/../../src/corelib/tools/qarraydata.h:208
#5  QGuiApplicationPrivate::createPlatformIntegration (this=0x5637552696f0) at kernel/qguiapplication.cpp:1481
#6  0x00007f4fb35b9b60 in QGuiApplicationPrivate::createEventDispatcher (this=<optimized out>) at kernel/qguiapplication.cpp:1498
#7  0x00007f4fb3188696 in QCoreApplicationPrivate::init (this=this@entry=0x5637552696f0) at kernel/qcoreapplication.cpp:852
#8  0x00007f4fb35bcaaf in QGuiApplicationPrivate::init (this=0x5637552696f0) at kernel/qguiapplication.cpp:1527
#9  0x00007f4fb35bd9e4 in QGuiApplication::QGuiApplication (this=0x7ffd8da2e540, argc=@0x7ffd8da2e4fc: 1, argv=0x7ffd8da2e6c8, flags=331520)
    at kernel/qguiapplication.h:203
#10 0x0000563753fd125a in main (argc=<optimized out>, argv=0x7ffd8da2e550) at /usr/src/debug/kglobalaccel-5.72.0-1.1.x86_64/src/runtime/main.cpp:47

Something odd is going on...

Notably we're both using openSUSE Tumbleweed with Qt 5.15.0.

(In reply to Nate Graham from comment #14)
> I'm able to reproduce the same crash here in my everything-built-from-source
> plasma session. I am seeing crashes in kglobalaccel and kactivitymanagerd.
> All of the crashes have the same backtrace as the ones for BingmyBong's
> plasmashell crashes:
> 
> #0  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
> #1  0x00007f4fb2d26539 in __GI_abort () at abort.c:79
> #2  0x00007f4fb2f68c27 in qt_message_fatal (message=<synthetic pointer>...,
> context=...) at global/qlogging.cpp:1914
> #3  QMessageLogger::fatal (this=this@entry=0x7ffd8da2e2b0,
> msg=msg@entry=0x7f4fb3a82f05 "%s") at global/qlogging.cpp:893
> #4  0x00007f4fb35b96d4 in init_platform (argv=<optimized out>,
> argc=@0x7ffd8da2e4fc: 1, platformThemeName=..., platformPluginPath=..., 
>     pluginNamesWithArguments=...) at
> ../../include/QtCore/../../src/corelib/tools/qarraydata.h:208
> #5  QGuiApplicationPrivate::createPlatformIntegration (this=0x5637552696f0)
> at kernel/qguiapplication.cpp:1481
> #6  0x00007f4fb35b9b60 in QGuiApplicationPrivate::createEventDispatcher
> (this=<optimized out>) at kernel/qguiapplication.cpp:1498
> #7  0x00007f4fb3188696 in QCoreApplicationPrivate::init
> (this=this@entry=0x5637552696f0) at kernel/qcoreapplication.cpp:852
> #8  0x00007f4fb35bcaaf in QGuiApplicationPrivate::init (this=0x5637552696f0)
> at kernel/qguiapplication.cpp:1527
> #9  0x00007f4fb35bd9e4 in QGuiApplication::QGuiApplication
> (this=0x7ffd8da2e540, argc=@0x7ffd8da2e4fc: 1, argv=0x7ffd8da2e6c8,
> flags=331520)
>     at kernel/qguiapplication.h:203
> #10 0x0000563753fd125a in main (argc=<optimized out>, argv=0x7ffd8da2e550)
> at /usr/src/debug/kglobalaccel-5.72.0-1.1.x86_64/src/runtime/main.cpp:47
> 
> Something odd is going on...
> 
> Notably we're both using openSUSE Tumbleweed with Qt 5.15.0.

Also I only started to notice it from 5.19.0 release because that's when the logout/lock widget started to break.

Since yesterdays upgrade to plasma-frameworks 5.73, lots of the other coredumps from kglobalaccel5, kdeconnectd, kactivitymanage, klauncher etc have ceased.

But i still get the logout coredumps from plasmashell and drkonqi, here is todays list.

Aug 14 08:51 core.drkonqi.1002.339aaeba2d3e4f6e8620d72043084edd.2556.1597391457000000000000.lz4
Aug 14 08:51 core.plasmashell.1002.339aaeba2d3e4f6e8620d72043084edd.2553.1597391457000000000000.lz4
Aug 14 08:51 core.plasmashell.1002.339aaeba2d3e4f6e8620d72043084edd.1479.1597391461000000000000.lz4
Aug 14 09:39 core.drkonqi.1001.339aaeba2d3e4f6e8620d72043084edd.9314.1597394354000000000000.lz
Aug 14 09:39 core.plasmashell.1001.339aaeba2d3e4f6e8620d72043084edd.9313.1597394354000000000000.lz4
Aug 14 09:39 core.plasmashell.1001.339aaeba2d3e4f6e8620d72043084edd.2812.1597394357000000000000.lz4
Aug 14 12:29 core.drkonqi.1000.339aaeba2d3e4f6e8620d72043084edd.21878.1597404549000000000000.lz4
Aug 14 12:29 core.plasmashell.1000.339aaeba2d3e4f6e8620d72043084edd.21877.1597404549000000000000.lz4
Aug 14 12:29 core.plasmashell.1000.339aaeba2d3e4f6e8620d72043084edd.9547.1597404558000000000000.lz4

(In reply to BingMyBong from comment #16)
> Since yesterdays upgrade to plasma-frameworks 5.73, lots of the other
> coredumps from kglobalaccel5, kdeconnectd, kactivitymanage, klauncher etc
> have ceased.
> 
> But i still get the logout coredumps from plasmashell and drkonqi, here is
> todays list.
> 
> Aug 14 08:51
> core.drkonqi.1002.339aaeba2d3e4f6e8620d72043084edd.2556.
> 1597391457000000000000.lz4
> Aug 14 08:51
> core.plasmashell.1002.339aaeba2d3e4f6e8620d72043084edd.2553.
> 1597391457000000000000.lz4
> Aug 14 08:51
> core.plasmashell.1002.339aaeba2d3e4f6e8620d72043084edd.1479.
> 1597391461000000000000.lz4
> Aug 14 09:39
> core.drkonqi.1001.339aaeba2d3e4f6e8620d72043084edd.9314.
> 1597394354000000000000.lz
> Aug 14 09:39
> core.plasmashell.1001.339aaeba2d3e4f6e8620d72043084edd.9313.
> 1597394354000000000000.lz4
> Aug 14 09:39
> core.plasmashell.1001.339aaeba2d3e4f6e8620d72043084edd.2812.
> 1597394357000000000000.lz4
> Aug 14 12:29
> core.drkonqi.1000.339aaeba2d3e4f6e8620d72043084edd.21878.
> 1597404549000000000000.lz4
> Aug 14 12:29
> core.plasmashell.1000.339aaeba2d3e4f6e8620d72043084edd.21877.
> 1597404549000000000000.lz4
> Aug 14 12:29
> core.plasmashell.1000.339aaeba2d3e4f6e8620d72043084edd.9547.
> 1597404558000000000000.lz4

Update:
Just got a kglobalaccel5 coredump when i used the logout/lock widget instead of logging out via the menu option.

On my Arch Linux kglobalaccel5 is still crashing after logout from X11 session.

(In reply to BingMyBong from comment #17)
> (In reply to BingMyBong from comment #16)
> > Since yesterdays upgrade to plasma-frameworks 5.73, lots of the other
> > coredumps from kglobalaccel5, kdeconnectd, kactivitymanage, klauncher etc
> > have ceased.
> > 
> > But i still get the logout coredumps from plasmashell and drkonqi, here is
> > todays list.
> > 
> > Aug 14 08:51
> > core.drkonqi.1002.339aaeba2d3e4f6e8620d72043084edd.2556.
> > 1597391457000000000000.lz4
> > Aug 14 08:51
> > core.plasmashell.1002.339aaeba2d3e4f6e8620d72043084edd.2553.
> > 1597391457000000000000.lz4
> > Aug 14 08:51
> > core.plasmashell.1002.339aaeba2d3e4f6e8620d72043084edd.1479.
> > 1597391461000000000000.lz4
> > Aug 14 09:39
> > core.drkonqi.1001.339aaeba2d3e4f6e8620d72043084edd.9314.
> > 1597394354000000000000.lz
> > Aug 14 09:39
> > core.plasmashell.1001.339aaeba2d3e4f6e8620d72043084edd.9313.
> > 1597394354000000000000.lz4
> > Aug 14 09:39
> > core.plasmashell.1001.339aaeba2d3e4f6e8620d72043084edd.2812.
> > 1597394357000000000000.lz4
> > Aug 14 12:29
> > core.drkonqi.1000.339aaeba2d3e4f6e8620d72043084edd.21878.
> > 1597404549000000000000.lz4
> > Aug 14 12:29
> > core.plasmashell.1000.339aaeba2d3e4f6e8620d72043084edd.21877.
> > 1597404549000000000000.lz4
> > Aug 14 12:29
> > core.plasmashell.1000.339aaeba2d3e4f6e8620d72043084edd.9547.
> > 1597404558000000000000.lz4
> 
> Update:
> Just got a kglobalaccel5 coredump when i used the logout/lock widget instead
> of logging out via the menu option.

UPDATE:  i spoke too soon, i've now got loads of kglobalaccel5 coredumps today.

My plasmashell crashes seem to have stopped.  All i've done today is "KillUserProcesses=yes in /etc/systemd/logind.conf" and "sudo systemctl disable --now lvm2-monitor" and rebooted.

I'm still getting coredumps of kglobalaccel5 (8 files), klauncher, kscreen_backend, kded5 for one user and kglobalaccel5, kded5 (2 files), drkonqi for a different user.
I cant get any backtraces for these files -  i get this error "Missing separate debuginfo for the main executable file" from gdb.

I wonder if some of these are surfaced by: 9be7dedb87ea574916f0f8a2837eaf7b19a7a166 in p-w.

The old XSManager would kill the app before X quit, which would prevent some of these?

logout from Wayland session causes several coredumps on neon unstable.

Operating System: KDE neon Unstable Edition
KDE Plasma Version: 5.19.80
KDE Frameworks Version: 5.75.0
Qt Version: 5.15.0

Tue 2020-09-15 10:58:19 -03   15918  1000  1003   6 present   /usr/bin/distro-release-notifier
Tue 2020-09-15 10:58:22 -03   15839  1000  1003   6 present   /usr/lib/x86_64-linux-gnu/libexec/kactivitymanagerd
Tue 2020-09-15 10:58:24 -03   15708  1000  1003   6 present   /usr/bin/kwalletd5
Tue 2020-09-15 10:58:24 -03   15777  1000  1003   6 present   /usr/bin/kded5
Tue 2020-09-15 10:58:24 -03   24718  1000  1003   6 present   /usr/lib/x86_64-linux-gnu/libexec/drkonqi
Tue 2020-09-15 10:58:25 -03   24734  1000  1003   6 present   /usr/lib/x86_64-linux-gnu/libexec/drkonqi
Tue 2020-09-15 10:58:25 -03   24768  1000  1003   6 present   /usr/lib/x86_64-linux-gnu/libexec/drkonqi
Tue 2020-09-15 10:58:25 -03   24767  1000  1003   6 present   /usr/bin/kded5
Tue 2020-09-15 10:58:28 -03   19294  1000  1003   6 present   /usr/bin/krunner

(In reply to David Edmundson from comment #21)
> I wonder if some of these are surfaced by:
> 9be7dedb87ea574916f0f8a2837eaf7b19a7a166 in p-w.
> 
> The old XSManager would kill the app before X quit, which would prevent some
> of these?

Thanks, reverting this commit fixes massive core dumps spurt on logout. I'll attach login/logout session for x11 and wayland and a patch I used to revert the changes for plasma 5.20.2 on Arch Linux. But i think the underlying issue persist in which display server gets killed *before* processes relying on it.

Created attachment 132836 [details]
unpatched login/logout session

Created attachment 132837 [details]
patched login/logout session

Created attachment 132838 [details]
patch for plasma-workspace 5.20.2 used on Arch Linux reverting 9be7dedb87ea574916f0f8a2837eaf7b19a7a166

>But i think the underlying issue persist in which display server gets killed *before* processes relying on it.

Yeah, that's a somewhat separate issue. Session management will just help with the graceful teardown case.

*** Bug 422322 has been marked as a duplicate of this bug. ***

Git commit 9e641d41717911f835fba59eb5fab6bbf97f8502 by David Edmundson.
Committed on 11/11/2020 at 23:03.
Pushed by davidedmundson into branch 'master'.

Revert "Use new simpler way to disable session management in services"

The two ways of disabling session management have the same impact on the
session being saved, but there is one behavioural side-effect that
turned out to be less ideal.

By disabling completely we don't follow the session manager telling the
application to quit. That's not something needed with the systemd boot,
but for the legacy boot effectively we were just closing applications by
ripping the X connection away from under them.

Some applications are bad at handling this and this led to a bunch of
crashes or dangling processes at logout.

This reverts commit 9be7dedb87ea574916f0f8a2837eaf7b19a7a166.

M  +7    -1    gmenu-dbusmenu-proxy/main.cpp
M  +9    -1    krunner/main.cpp
M  +9    -1    shell/main.cpp
M  +7    -1    xembed-sni-proxy/main.cpp

https://invent.kde.org/plasma/plasma-workspace/commit/9e641d41717911f835fba59eb5fab6bbf97f8502

Git commit da34fd073f6b361fde1fdcee559d60e8c0268cd6 by David Edmundson.
Committed on 11/11/2020 at 23:05.
Pushed by davidedmundson into branch 'Plasma/5.20'.

Revert "Use new simpler way to disable session management in services"

The two ways of disabling session management have the same impact on the
session being saved, but there is one behavioural side-effect that
turned out to be less ideal.

By disabling completely we don't follow the session manager telling the
application to quit. That's not something needed with the systemd boot,
but for the legacy boot effectively we were just closing applications by
ripping the X connection away from under them.

Some applications are bad at handling this and this led to a bunch of
crashes or dangling processes at logout.

This reverts commit 9be7dedb87ea574916f0f8a2837eaf7b19a7a166.


(cherry picked from commit 9e641d41717911f835fba59eb5fab6bbf97f8502)

M  +7    -1    gmenu-dbusmenu-proxy/main.cpp
M  +9    -1    krunner/main.cpp
M  +9    -1    shell/main.cpp
M  +7    -1    xembed-sni-proxy/main.cpp

https://invent.kde.org/plasma/plasma-workspace/commit/da34fd073f6b361fde1fdcee559d60e8c0268cd6

Is there more to do here, or can this be closed?

(In reply to Nate Graham from comment #31)
> Is there more to do here, or can this be closed?

From my POV, yes, the apps still report that X11/display died, but there are no coredumps anymore. As I'm not the original submitter, it would be good to wait for feedback from others.

(In reply to Nate Graham from comment #31)
> Is there more to do here, or can this be closed?

I'm still getting coredumps but this could be a separate/new issue. I now get 9 instances of core.qdbus, one instance of kglobalaccel5, kded5, drkonqi, kded5 in that order every time now. 
I run a kdialog script on logout and it uses qdbus to display progress of my backups via rsync and this was working fine until recently, now it just shows the first message but completes the backup okay.
If this is deemed a separate issue, i'm happy for this to bug to be closed and i'll start a new one.

I've "fixed" most of my coredumps on logout (replaced qdbus with qdbus-qt5) so i'm just left with these ones
-rw-r-----+ 1 root root  769148 Nov 26 15:58 core.kglobalaccel5.1002.f4a0442535264a189e6774e195874e79.22064.1606406311000000.lz4
-rw-r-----+ 1 root root  768860 Nov 26 15:58 core.kglobalaccel5.1002.f4a0442535264a189e6774e195874e79.22076.1606406312000000.lz4
-rw-r-----+ 1 root root 1056917 Nov 26 15:58 core.drkonqi.1002.f4a0442535264a189e6774e195874e79.22080.1606406312000000.lz4
-rw-r-----+ 1 root root  734967 Nov 26 15:58 core.kded5.1002.f4a0442535264a189e6774e195874e79.22079.1606406312000000.lz4
-rw-r-----+ 1 root root  769476 Nov 26 15:58 core.kglobalaccel5.1002.f4a0442535264a189e6774e195874e79.22107.1606406312000000.lz4
-rw-r-----+ 1 root root  769270 Nov 26 15:58 core.kglobalaccel5.1002.f4a0442535264a189e6774e195874e79.22141.1606406313000000.lz4
-rw-r-----+ 1 root root  769128 Nov 26 15:58 core.kglobalaccel5.1002.f4a0442535264a189e6774e195874e79.22168.1606406314000000.lz4
-rw-r-----+ 1 root root 5214281 Nov 26 15:58 core.kded5.1002.f4a0442535264a189e6774e195874e79.18160.1606406313000000.lz4

I use Manjaro KDE, with Plasma 5.20.4 and am affected by this bug. Every time I logout/login, the system usually hangs for long and there are a few coredumps more in my /var/lib/systemd/coredump:

core.pamac-tray-appi*.zst
core.plasmashell*.zst

I tried to fix the issue by the following changes, but it didn't help:

~/.xinitrc:
DEFAULT_SESSION=startplasma-x11

/etc/systemd/logind.conf.d/override.conf:
KillUserProcesses=yes


The weirdest part is that the bug doesn't seem consistent. I continued to test logout/login multiple times with completely different results:

reboot > login as a new user A > logout > login > huge lag > system seems to work normally > logout > login as my default user B > huge lag > systems seems to work normally > logout > login as B > no lag(!) > systems seems to work normally > logout > login as B > huge lag > can’t see my desktop normally, can’t minimize the only window that appeared on screen: Rambox, I could just go to TTY to reboot the system > login as B > logout > login as B > huge lag > not all services has been loaded and my tiling window manager doesn’t work > shutdown

I tested a clean install of Fedora KDE spin and it's reproduceable OOTB, both before and after full system upgrades. This breaks multi-user desktops and should be looked at with higher priority.

Hi,

i have a fully updated OpenMandriva cooker with Plasma 5.20.4 and KDE Frameworks 5.77.0

[root@tpg-virtualbox systemd]# rpm -qa | grep plasma-workspace
plasma-workspace-wayland-5.20.4-3.x86_64
plasma-workspace-5.20.4-3.x86_64
plasma-workspace-x11-5.20.4-3.x86_64

After hitting logout on Plasma Wayland session i see these in coredumpctl:
Fri 2020-12-11 12:30:07 CET    1955  1001  1006   6 present   /usr/lib64/libexec/drkonqi
Fri 2020-12-11 12:30:08 CET     896  1001  1006   6 present   /usr/lib64/libexec/kdeconnectd
Fri 2020-12-11 12:30:08 CET     921  1001  1006   6 present   /usr/lib64/libexec/org_kde_powerdevil
Fri 2020-12-11 12:30:18 CET     843  1001  1006   6 present   /usr/bin/kded5
Fri 2020-12-11 12:30:18 CET    1954  1001  1006   6 present   /usr/bin/plasmashell


gru 11 12:29:56 tpg-virtualbox su[1089]: pam_unix(su:session): session closed for user root
gru 11 12:29:56 tpg-virtualbox systemd[754]: app-org.kde.konsole-919a169276f3431ba46e448492368421.scope: Succeeded.
gru 11 12:29:56 tpg-virtualbox plasmashell[1954]: file:///usr/lib64/qt5/qml/org/kde/plasma/components/ModelContextMenu.qml:38:1: QML ModelContextMenu: Ac>
gru 11 12:29:57 tpg-virtualbox plasmashell[1954]: file:///usr/share/plasma/plasmoids/org.kde.plasma.printmanager/contents/ui/PopupDialog.qml:91:17: Unabl>
gru 11 12:29:57 tpg-virtualbox kaccess[870]: The X11 connection broke (error 1). Did the X11 server die?
gru 11 12:29:57 tpg-virtualbox kactivitymanagerd[912]: The X11 connection broke (error 1). Did the X11 server die?
gru 11 12:29:57 tpg-virtualbox kernel: A fatal guest X Window error occurred.  This may just mean that the Window system was shut down while the client w>
gru 11 12:29:57 tpg-virtualbox kernel: A fatal guest X Window error occurred.  This may just mean that the Window system was shut down while the client w>
gru 11 12:29:57 tpg-virtualbox kded5[843]: ktp-kded-module: activity service not running, user account presences won't load or save
gru 11 12:29:57 tpg-virtualbox kernel: A fatal guest X Window error occurred.  This may just mean that the Window system was shut down while the client w>
gru 11 12:29:57 tpg-virtualbox kernel: Terminating ...
gru 11 12:29:57 tpg-virtualbox kernel: Terminating HGCM thread ...
gru 11 12:29:57 tpg-virtualbox kernel: Terminating X11 thread ...
gru 11 12:29:57 tpg-virtualbox systemd[754]: dbus-:1.2-org.kde.ActivityManager@0.service: Succeeded.
gru 11 12:29:57 tpg-virtualbox org_kde_powerdevil[921]: The Wayland connection broke. Did the Wayland compositor die?
gru 11 12:29:57 tpg-virtualbox kdeconnectd[896]: The Wayland connection broke. Did the Wayland compositor die?
gru 11 12:29:57 tpg-virtualbox drkonqi[1955]: The Wayland connection broke. Did the Wayland compositor die?
gru 11 12:29:57 tpg-virtualbox plasmashell[1954]: The Wayland connection broke. Did the Wayland compositor die?
gru 11 12:29:57 tpg-virtualbox kded5[843]: The Wayland connection broke. Did the Wayland compositor die?
gru 11 12:29:58 tpg-virtualbox drkonqi[1989]: Failed to create wl_display (No such file or directory)
gru 11 12:29:58 tpg-virtualbox drkonqi[1989]: qt.qpa.plugin: Could not load the Qt platform plugin "wayland" in "" even though it was found.
gru 11 12:29:58 tpg-virtualbox drkonqi[1989]: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the appli>
                                              
                                              Available platform plugins are: wayland-org.kde.kwin.qpa, eglfs, wayland-egl, wayland, wayland-xcomposite-e>
gru 11 12:29:58 tpg-virtualbox systemd[1]: Created slice system-systemd\x2dcoredump.slice.
gru 11 12:29:58 tpg-virtualbox systemd[1]: Started Process Core Dump (PID 1994/UID 0).
gru 11 12:29:58 tpg-virtualbox drkonqi[1993]: Failed to create wl_display (No such file or directory)
gru 11 12:29:58 tpg-virtualbox drkonqi[1993]: qt.qpa.plugin: Could not load the Qt platform plugin "wayland" in "" even though it was found.
gru 11 12:29:58 tpg-virtualbox drkonqi[1993]: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the appli>
                                              
                                              Available platform plugins are: wayland-org.kde.kwin.qpa, eglfs, wayland-egl, wayland, wayland-xcomposite-e>
gru 11 12:29:58 tpg-virtualbox kernel: Error waiting for X11 thread to terminate: VERR_TIMEOUT
gru 11 12:29:58 tpg-virtualbox kernel: Terminating threads done
gru 11 12:29:58 tpg-virtualbox sddm-helper[745]: pam_kwallet5(sddm:session): pam_kwallet5: pam_sm_close_session
gru 11 12:29:58 tpg-virtualbox sddm-helper[745]: pam_unix(sddm:session): session closed for user tpg
gru 11 12:29:58 tpg-virtualbox sddm-helper[745]: pam_kwallet5(sddm:setcred): pam_kwallet5: pam_sm_setcred
gru 11 12:29:58 tpg-virtualbox systemd-logind[541]: Session 2 logged out. Waiting for processes to exit.

Similar issues here on OpenMandriva Cooker with Plasma 5.20.4 and Frameworks 5.77.0.

Xsession works fine.

On Wayland session.

First loging = crash:
https://pastebin.com/3Hius7Q2

Log out and again log in to Plasma session and then I see a lot of core dumps in /var/lib/systemd/coredump.
As example: 3x plasmashell, 2x kdeconnect, 2x kded5, 2x kde_powerde, akonadiderver or kwin_wayland.

Here is my part of journalctl with some logs and crash
https://pastebin.com/bs07i96x

At this point the most common ones have been fixed. For people still experiencing crashes on login/logout, please open new bu reports--one per crash. That will get them fixed faster than continuing to use this as a sort of umbrella bug report. Thanks!

My bug reports related to login/logout:

bug 430736
bug 430740
bug 430741
bug 430739

(In reply to Patrick Silva from comment #40)
> My bug reports related to login/logout:
> 
> bug 430736
> bug 430740
> bug 430741
> bug 430739

I think it's better to add them to "See also" on top.
It will be hard to find them here.
https://bugs.kde.org/page.cgi?id=fields.html#see_also

*** Bug 424488 has been marked as a duplicate of this bug. ***

*** Bug 432216 has been marked as a duplicate of this bug. ***

*** Bug 409448 has been marked as a duplicate of this bug. ***

*** Bug 421436 has been marked as a duplicate of this bug. ***

*** Bug 392556 has been marked as a duplicate of this bug. ***

*** Bug 393352 has been marked as a duplicate of this bug. ***

*** Bug 399175 has been marked as a duplicate of this bug. ***