Kscreenlocker_greet crashing

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1

Seeing many errors in journalctl about kscreenlocker_greeting unable to load the wayland plugin even though it is found. Also seeing messages that the screenlocker is broken and to go to another console and do ‘loginctl stop-session2’ (or something like that; didn’t take a photo of that screen.) That fix hasn’t worked as the other consoles seem to be dead by that time.

Sample of what I’m seeing:

Jun 30 06:35:39 manji kernel: kscreenlocker_g[2552]: segfault at 2047f4600810 ip 00007f4806a3ef69 sp 00007ffc4e37c790 error 4 in libQt6Qml.so.6.7.1[7f48068a5000+3a2000] likely on CPU 4 (c>
Jun 30 06:35:39 manji kernel: Code: b0 48 39 45 b8 73 34 66 2e 0f 1f 84 00 00 00 00 00 48 8b 78 f8 48 8d 50 f8 83 05 71 4e 2f 00 01 48 89 de 48 89 55 b0 48 8b 07 <48> 8b 40 10 ff 50 28 48>
Jun 30 06:35:39 manji kwin_wayland_wrapper[1474]: not a valid new object id (2), message get_registry(n)
Jun 30 06:35:39 manji kwin_wayland_wrapper[1474]: error in client communication (pid 1474)
Jun 30 06:35:39 manji kwin_wayland_wrapper[3491]: wl_display#1: error 1: invalid arguments for wl_display#1.get_registry
Jun 30 06:35:39 manji kscreenlocker_greet[3491]: qt.qpa.wayland: Loading shell integration failed.
Jun 30 06:35:39 manji kscreenlocker_greet[3491]: qt.qpa.wayland: Attempted to load the following shells QList("layer-shell")
Jun 30 06:35:39 manji kscreenlocker_greet[3491]: qt.qpa.plugin: Could not load the Qt platform plugin "wayland" in "" even though it was found.
Jun 30 06:35:39 manji kscreenlocker_greet[3491]: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.
                                                 
                                                 Available platform plugins are: xcb, vnc, minimalegl, eglfs, wayland, linuxfb, minimal, vkkhrdisplay, offscreen, wayland-egl.
Jun 30 06:35:39 manji kscreenlocker_greet[3495]: qt.qpa.wayland: Loading shell integration failed.
Jun 30 06:35:39 manji kscreenlocker_greet[3495]: qt.qpa.wayland: Attempted to load the following shells QList("layer-shell")
Jun 30 06:35:39 manji kscreenlocker_greet[3495]: qt.qpa.plugin: Could not load the Qt platform plugin "wayland" in "" even though it was found.
Jun 30 06:35:39 manji kscreenlocker_greet[3495]: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.
                                                 
                                                 Available platform plugins are: xcb, vnc, minimalegl, eglfs, wayland, linuxfb, minimal, vkkhrdisplay, offscreen, wayland-egl.
Jun 30 06:35:39 manji kscreenlocker_greet[3498]: qt.qpa.wayland: Loading shell integration failed.
Jun 30 06:35:39 manji kscreenlocker_greet[3498]: qt.qpa.wayland: Attempted to load the following shells QList("layer-shell")
Jun 30 06:35:39 manji kscreenlocker_greet[3498]: qt.qpa.plugin: Could not load the Qt platform plugin "wayland" in "" even though it was found.
Jun 30 06:35:39 manji kscreenlocker_greet[3498]: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.
                                                 
                                                 Available platform plugins are: xcb, vnc, minimalegl, eglfs, wayland, linuxfb, minimal, vkkhrdisplay, offscreen, wayland-egl.

This appears to be the same as an Arch issue: https://bbs.archlinux.org/viewtopic.php?id=294523

In that issue it was traced to libpcre2 and fixed with 10.43-3, I have 10.43-4, so it doesn’t seem to be that.

General info about my system:

Operating System: Manjaro Linux 
KDE Plasma Version: 6.0.5
KDE Frameworks Version: 6.2.0
Qt Version: 6.7.1
Kernel Version: 6.9.0-MANJARO (64-bit)
Graphics Platform: Wayland
Processors: 12 × 11th Gen Intel® Core™ i5-11400 @ 2.60GHz
Memory: 62.6 GiB of RAM
Graphics Processor: Mesa Intel® Graphics
Manufacturer: Micro-Star International Co., Ltd.
Product Name: MS-7D18
System Version: 1.0
2

You are not alone, I have encountered the same problem after a recent update.

Jul 03 10:18:24 HOSTNAME kernel: kscreenlocker_g[14029]: segfault at 8 ip 00007f2abb1aaee4 sp 00007ffe42d17d28 error 4 in libQt6Gui.so.6.7.2[7f2abb0d9000+618000] likely on CPU 10 (core 20, socket 0)
Jul 03 10:18:25 HOSTNAME kscreenlocker_greet[14208]: qt.qpa.wayland: Loading shell integration failed.
Jul 03 10:18:25 HOSTNAME kscreenlocker_greet[14208]: qt.qpa.wayland: Attempted to load the following shells QList("layer-shell")
Jul 03 10:18:25 HOSTNAME kscreenlocker_greet[14208]: qt.qpa.plugin: Could not load the Qt platform plugin "wayland" in "" even though it was found.
Jul 03 10:18:25 HOSTNAME kscreenlocker_greet[14208]: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.
Jul 03 10:18:25 HOSTNAME kscreenlocker_greet[14212]: qt.qpa.wayland: Loading shell integration failed.
Jul 03 10:18:25 HOSTNAME kscreenlocker_greet[14212]: qt.qpa.wayland: Attempted to load the following shells QList("layer-shell")
Jul 03 10:18:25 HOSTNAME kscreenlocker_greet[14212]: qt.qpa.plugin: Could not load the Qt platform plugin "wayland" in "" even though it was found.
Jul 03 10:18:25 HOSTNAME kscreenlocker_greet[14212]: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.
Jul 03 10:18:25 HOSTNAME kscreenlocker_greet[14216]: qt.qpa.wayland: Loading shell integration failed.
Jul 03 10:18:25 HOSTNAME kscreenlocker_greet[14216]: qt.qpa.wayland: Attempted to load the following shells QList("layer-shell")
Jul 03 10:18:25 HOSTNAME kscreenlocker_greet[14216]: qt.qpa.plugin: Could not load the Qt platform plugin "wayland" in "" even though it was found.
Jul 03 10:18:25 HOSTNAME kscreenlocker_greet[14216]: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.
3

To resolve errors with kscreenlocker_greeting on Wayland:

  1. Ensure all Wayland and KDE packages are up-to-date.
  2. Check for missing dependencies or reinstall relevant packages.
  3. Consider switching to a different TTY and restarting the session using loginctl terminate-session <session-id>.
4

Thanks for the suggestions. In the course of persuing your first two items, an update got as far as updating the Manjaro keyring, whereupon the system locked up completely. This was after a pacman -Qi resulted in an error about a double free and zsh crashed, so I will need to get to the bottom of these issues to be able to update the system.

As for item 3, as I related earlier, the other TTYs were not responsive when the original issue occurred.

5
  1. System locked up during Manjaro keyring update after pacman -Qi error and zsh crash.
  2. Need to resolve these issues to update the system properly.
  3. Other TTYs were unresponsive during the original issue.