Can't login to Xorg sessions if desktop zoom was already enabled

[Arnold Loubriat]

After upgrading from Ubuntu 22.10 to Ubuntu 23.04, I am unable to login to my session as I always get the "Oh no! Something has gone wrong." error message.

I have screen magnifier enabled, but disabling it using:
gsettings set org.gnome.desktop.a11y.applications screen-magnifier-enabled false
makes the issue disappear. I can reproduce the bug inside a virtual machine on Windows as well, with different hardware.
The only piece of log I can find and that might be linked to the issue is:

avril 29 11:21:19 arnold-ThinkStation-P620 systemd[6918]: Starting <email address hidden> - GNOME Shell on X11...
avril 29 11:21:19 arnold-ThinkStation-P620 dbus-daemon[6942]: [session uid=1000 pid=6942] Activating via systemd: service name='org.freedesktop.impl.portal.desktop.gtk' unit='xdg-desktop-portal-gtk.service' requested by ':1.52' (uid=1000 pid=7773 comm="/usr/libexec/xdg-desktop-portal" label="unconfined")
avril 29 11:21:19 arnold-ThinkStation-P620 systemd[6918]: Starting xdg-desktop-portal-gtk.service - Portal service (GTK/GNOME implementation)...
avril 29 11:21:19 arnold-ThinkStation-P620 at-spi-bus-launcher[7212]: dbus-daemon[7212]: Activating service name='org.a11y.atspi.Registry' requested by ':1.5' (uid=1000 pid=7862 comm="/usr/libexec/xdg-desktop-portal-gtk" label="unconfined")
avril 29 11:21:19 arnold-ThinkStation-P620 dbus-daemon[6942]: [session uid=1000 pid=6942] Activating service name='org.gnome.ScreenSaver' requested by ':1.55' (uid=1000 pid=7862 comm="/usr/libexec/xdg-desktop-portal-gtk" label="unconfined")
avril 29 11:21:19 arnold-ThinkStation-P620 at-spi-bus-launcher[7212]: dbus-daemon[7212]: Successfully activated service 'org.a11y.atspi.Registry'
avril 29 11:21:19 arnold-ThinkStation-P620 at-spi-bus-launcher[7869]: SpiRegistry daemon is running with well-known name - org.a11y.atspi.Registry
avril 29 11:21:19 arnold-ThinkStation-P620 gnome-shell[7863]: Running GNOME Shell (using mutter 44.0) as a X11 window and compositing manager
avril 29 11:21:19 arnold-ThinkStation-P620 dbus-daemon[6942]: [session uid=1000 pid=6942] Successfully activated service 'org.gnome.ScreenSaver'
avril 29 11:21:19 arnold-ThinkStation-P620 gnome-session[7361]: gnome-session-binary[7361]: WARNING: Could not retrieve current screensaver active state: GDBus.Error:org.freedesktop.DBus.Error.NoReply: Message recipient disconnected from message bus without replying
avril 29 11:21:19 arnold-ThinkStation-P620 gnome-session-binary[7361]: WARNING: Could not retrieve current screensaver active state: GDBus.Error:org.freedesktop.DBus.Error.NoReply: Message recipient disconnected from message bus without replying
avril 29 11:21:19 arnold-ThinkStation-P620 dbus-daemon[6942]: [session uid=1000 pid=6942] Successfully activated service 'org.freedesktop.impl.portal.desktop.gtk'
avril 29 11:21:19 arnold-ThinkStation-P620 systemd[6918]: Started xdg-desktop-portal-gtk.service - Portal service (GTK/GNOME implementation).
avril 29 11:21:19 arnold-ThinkStation-P620 dbus-daemon[6942]: [session uid=1000 pid=6942] Successfully activated service 'org.freedesktop.portal.Desktop'
avril 29 11:21:19 arnold-ThinkStation-P620 systemd[6918]: Started xdg-desktop-portal.service - Portal service.
avril 29 11:21:19 arnold-ThinkStation-P620 snapd-desktop-i[7769]: New theme: gtk=Yaru icon=Yaru cursor=(null), sound=Yaru
avril 29 11:21:19 arnold-ThinkStation-P620 snapd-desktop-i[7769]: All available theme snaps installed
avril 29 11:21:19 arnold-ThinkStation-P620 gnome-shell[7984]: libEGL warning: DRI2: failed to authenticate
avril 29 11:21:19 arnold-ThinkStation-P620 kernel: gnome-shell[7863]: segfault at 18 ip 00007f7af86b2004 sp 00007ffeb1dc3a18 error 4 in libmutter-12.so.0.0.0[7f7af864a000+13d000] likely on CPU 15 (core 15, socket 0)
avril 29 11:21:19 arnold-ThinkStation-P620 kernel: Code: 00 00 00 00 66 90 f3 0f 1e fa 48 63 05 79 67 16 00 48 8b 04 07 c3 f3 0f 1e fa 48 8b 87 40 01 00 00 c3 0f 1f 40 00 f3 0f 1e fa <48> 8b 47 18 c3 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 8b 47 28 c3 0f
avril 29 11:21:20 arnold-ThinkStation-P620 systemd[6918]: <email address hidden>: Main process exited, code=dumped, status=11/SEGV
avril 29 11:21:20 arnold-ThinkStation-P620 systemd[6918]: <email address hidden>: Failed with result 'core-dump'.
avril 29 11:21:20 arnold-ThinkStation-P620 systemd[6918]: Failed to start <email address hidden> - GNOME Shell on X11.
avril 29 11:21:20 arnold-ThinkStation-P620 systemd[6918]: <email address hidden>: Scheduled restart job, restart counter is at 3.
avril 29 11:21:20 arnold-ThinkStation-P620 systemd[6918]: Stopped <email address hidden> - GNOME Shell on X11.
avril 29 11:21:20 arnold-ThinkStation-P620 systemd[6918]: <email address hidden>: Start request repeated too quickly.
avril 29 11:21:20 arnold-ThinkStation-P620 systemd[6918]: <email address hidden>: Failed with result 'core-dump'.
avril 29 11:21:20 arnold-ThinkStation-P620 systemd[6918]: Failed to start <email address hidden> - GNOME Shell on X11.
avril 29 11:21:20 arnold-ThinkStation-P620 systemd[6918]: <email address hidden>: Triggering OnFailure= dependencies.
avril 29 11:21:20 arnold-ThinkStation-P620 systemd[6918]: Reached target gnome-session-initialized.target - GNOME Session is initialized.
avril 29 11:21:20 arnold-ThinkStation-P620 systemd[6918]: Reached target gnome-session-x11-services.target - GNOME session X11 services.
avril 29 11:21:20 arnold-ThinkStation-P620 systemd[6918]: Reached target <email address hidden> - GNOME Session (session: ubuntu).
avril 29 11:21:20 arnold-ThinkStation-P620 systemd[6918]: Started gnome-session-failed.service - GNOME Session Failed lockdown screen (user).

So it seems like mutter crashes.
Thanks for looking into this.

[Ubuntu Foundations Team Bug Bot (crichton)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. It seems that your bug report is not filed about a specific source package though, rather it is just filed against Ubuntu in general. It is important that bug reports be filed about source packages so that people interested in the package can find the bugs about it. You can find some hints about determining what package your bug might be about at https://wiki.ubuntu.com/Bugs/FindRightPackage. You might also ask for help in the #ubuntu-bugs irc channel on Libera.chat.

To change the source package that this bug is filed about visit https://bugs.launchpad.net/ubuntu/+bug/2018155/+editstatus and add the package name in the text box next to the word Package.

[This is an automated message. I apologize if it reached you inappropriately; please just reply to this message indicating so.]

[Daniel van Vugt (vanvugt)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. It sounds like some part of the system has crashed. To help us find the cause of the crash please follow these steps:

1. Look in /var/crash for crash files and if found run:
    ubuntu-bug YOURFILE.crash
Then tell us the ID of the newly-created bug.

2. If step 1 failed then look at https://errors.ubuntu.com/user/ID where ID is the content of file /var/lib/whoopsie/whoopsie-id on the machine. Do you find any links to recent problems on that page? If so then please send the links to us.

Please take care to avoid attaching .crash files to bugs as we are unable to process them as file attachments. It would also be a security risk for yourself.

[Arnold Loubriat (datatriny)]

Hello Daniel,
There is no crash file generated, and going to the webpage you provided shows no error that could be linked to this issue.
But as I mentioned above, the issue should be very easy to reproduce.

[Daniel van Vugt (vanvugt)]

Confirmed - the segfault is mentioned in the log but failing to leave any crash file.

I've reconfigured my system to produce core files instead and got:

Program terminated with signal SIGSEGV, Segmentation fault.
#0 meta_display_get_x11_display (display=0x0) at ../src/core/display.c:2456
Downloading source file /usr/src/mutter-44.0-2ubuntu4/obj-x86_64-linux-gnu/../src/core/display.c
2456 return display->x11_display;
[Current thread is 1 (Thread 0x7f495063c600 (LWP 2641))]
(gdb) bt
#0 meta_display_get_x11_display (display=0x0) at ../src/core/display.c:2456
#1 0x00007f4954ae206b in meta_cursor_sprite_xfixes_initable_init
    (initable=0x5643a0a1b1e0, cancellable=<optimised out>, error=0x7ffeb6a7cf00) at ../src/backends/x11/cm/meta-cursor-sprite-xfixes.c:134
#2 0x00007f49550a89c4 in g_initable_new_valist
    (object_type=<optimised out>, first_property_name=0x7f4954ba6c50 "display", var_args=var_args@entry=0x7ffeb6a7ce10, cancellable=cancellable@entry=0x0, error=error@entry=0x7ffeb6a7cf00) at ../../../gio/ginitable.c:250
#3 0x00007f49550a8abd in g_initable_new
    (object_type=<optimised out>, cancellable=cancellable@entry=0x0, error=error@entry=0x7ffeb6a7cf00, first_property_name=first_property_name@entry=0x7f4954ba6c50 "display") at ../../../gio/ginitable.c:164
#4 0x00007f4954aea82e in meta_cursor_sprite_xfixes_new
    (error=0x7ffeb6a7cf00, cursor_tracker=0x56439f897810, display=0x0)
    at ../src/backends/x11/cm/meta-cursor-sprite-xfixes.c:110
#5 ensure_xfixes_cursor (tracker_x11=tracker_x11@entry=0x56439f897810)
    at ../src/backends/x11/meta-cursor-tracker-x11.c:94
#6 0x00007f4954aea8bd in meta_cursor_tracker_x11_get_sprite
    (tracker=0x56439f897810)
    at ../src/backends/x11/meta-cursor-tracker-x11.c:162
#7 0x00007f4954a76fde in meta_cursor_tracker_get_sprite
    (tracker=<optimised out>) at ../src/backends/meta-cursor-tracker.c:361
#8 0x00007f4954c2a8b6 in ffi_call_unix64 () at ../src/x86/unix64.S:104
#9 0x00007f4954c2734d in ffi_call_int
    (cif=cif@entry=0x5643a0a06b60, fn=<optimised out>, rvalue=<optimised out>, avalue=<optimised out>, closure=closure@entry=0x0) at ../src/x86/ffi64.c:673
#10 0x00007f4954c29f33 in ffi_call
    (cif=0x5643a0a06b60, fn=<optimised out>, rvalue=<optimised out>, avalue=<optimised out>) at ../src/x86/ffi64.c:710
#11 0x00007f4954de51f9 in Gjs::Function::invoke(JSContext*, JS::CallArgs const&, JS::Handle<JSObject*>, _GIArgument*)
    (this=<optimised out>, context=0x56439fb35460, args=<optimised out>, this_obj=..., r_value=<optimised out>)
    at /usr/src/gjs-1.76.0-3/obj-x86_64-linux-gnu/../gi/function.cpp:1050

[yoyoma2 (sinbad-4273)]

On ubuntu 23.10 (wayland disabled so required on-screen keyboard can work) I clicked on Zoom in the Accessibility menu to see something small. Things got big but I couldn't move the zoomed area with the mouse. No crash because the zoomed area would randomly shift on occasion. Impossible to go and turn zoom off.

Logged in and rebooted from another machine but the Zoomed setting is remembered when you attempt to log into the GUI. Logged in remotely, enabled wayland, logged into the GUI, turned off Zoom, disabled wayland, rebooted.

System recovered!

Can the Zoom toggle be removed from the accessibility menu? I've installed the Magnus screen magnifier as a workaround and it works in Xorg.