Opening multitasking view after disconnecting external monitor crashes the secure session

[leopmarcos]

What Happened?

If I start a secure session with an external monitor connected to my laptop and eventually disconnect that monitor, open windows are moved to the laptop screen, as expected. After that, however, if I enter multitasking view (either by clicking the shortcut in the dock or by using a keyboard shortcut), the entire session crashes and I get sent back to the login screen. This is consistent in my setup and I am able to reproduce the issue through the steps described below.

In my setup, the external monitor is configured as the primary display (i.e., where the dock and the panel show).

I am using the RC for OS8 and I have run all updates.

Steps to Reproduce

1. Have a second monitor connected to laptop before logging in.
2. Log in to the secure session.
3. Open any app on either monitor.
4. Disconnect second monitor.
5. Enter multitasking view.

Expected Behavior

I would expect to enter multitasking view with no issues to be able to quickly reorganize my windows.

OS Version

8.x (Early Access)

Session Type

Secure Session (Wayland)

Software Version

Latest release (I have run all updates)

Log Output

No response

Hardware Info

Processor: Intel Core i5 8250U @1.6GHz
Graphics: Intel UHD Graphics 620
Dedicated graphics card: AMD Radeon 535
RAM: 8GB

Laptop screen resolution: 1920x1080
External screen resolution: 2560x1440

[teamcons]

I can reproduce the issue somewhat
1/ disconnecting the main/only monitor
2/ opening multitasking
3/ connecting the main monitor

on reconnecting the monitor i hear my BT speaker do the disconnect / reconnect sound, and my monitor wake up to lightdm.
i cannot determine looking at dmesg, but there is this line

[ 2697.946574] traps: gala[6449] general protection fault ip:726b3c1ad525 sp:7ffe101365e0 error:0 in libgobject-2.0.so.0.8000.0[726b3c17f000+37000]

Immediate vincinity :

[  907.042514] workqueue: delayed_fput hogged CPU for >10000us 32 times, consider switching to WQ_UNBOUND
[ 2296.510636] kauditd_printk_skb: 90 callbacks suppressed
[ 2296.510644] audit: type=1400 audit(1731259736.073:431): apparmor="AUDIT" operation="userns_create" class="namespace" info="Userns create - transitioning profile" profile="unconfined" pid=10713 comm="bwrap" requested="userns_create" target="unprivileged_userns"
[ 2296.513632] audit: type=1400 audit(1731259736.077:432): apparmor="DENIED" operation="capable" class="cap" profile="unprivileged_userns" pid=10714 comm="bwrap" capability=8  capname="setpcap"
[ 2296.513770] audit: type=1400 audit(1731259736.077:433): apparmor="DENIED" operation="capable" class="cap" profile="unprivileged_userns" pid=10714 comm="bwrap" capability=12  capname="net_admin"
[ 2379.009176] audit: type=1400 audit(1731259818.575:434): apparmor="AUDIT" operation="userns_create" class="namespace" info="Userns create - transitioning profile" profile="unconfined" pid=10755 comm="bwrap" requested="userns_create" target="unprivileged_userns"
[ 2379.011858] audit: type=1400 audit(1731259818.578:435): apparmor="DENIED" operation="capable" class="cap" profile="unprivileged_userns" pid=10757 comm="bwrap" capability=8  capname="setpcap"
[ 2379.012046] audit: type=1400 audit(1731259818.578:436): apparmor="DENIED" operation="capable" class="cap" profile="unprivileged_userns" pid=10757 comm="bwrap" capability=12  capname="net_admin"
[ 2386.429270] audit: type=1400 audit(1731259825.996:437): apparmor="AUDIT" operation="userns_create" class="namespace" info="Userns create - transitioning profile" profile="unconfined" pid=10772 comm="bwrap" requested="userns_create" target="unprivileged_userns"
[ 2391.311461] audit: type=1400 audit(1731259830.877:438): apparmor="AUDIT" operation="userns_create" class="namespace" info="Userns create - transitioning profile" profile="unconfined" pid=10783 comm="bwrap" requested="userns_create" target="unprivileged_userns"
[ 2391.312806] audit: type=1400 audit(1731259830.878:439): apparmor="DENIED" operation="capable" class="cap" profile="unprivileged_userns" pid=10784 comm="bwrap" capability=8  capname="setpcap"
[ 2391.312902] audit: type=1400 audit(1731259830.878:440): apparmor="DENIED" operation="capable" class="cap" profile="unprivileged_userns" pid=10784 comm="bwrap" capability=12  capname="net_admin"
[ 2493.955577] perf: interrupt took too long (2520 > 2500), lowering kernel.perf_event_max_sample_rate to 79000
[ 2697.946574] traps: gala[6449] general protection fault ip:726b3c1ad525 sp:7ffe101365e0 error:0 in libgobject-2.0.so.0.8000.0[726b3c17f000+37000]
[ 2699.239162] rfkill: input handler enabled
[ 2714.575651] rfkill: input handler disabled

Padded in both directions by some audit: apparmor ubuntu_pro_esm_cache mknod access denied junk that may be irrelevant

[leopmarcos]

After updating gala to 8.0.4 I can no longer reproduce this issue on my setup and everything seems to be working properly.