Permission issues running tkey-ssh-agent with systemd on Ubuntu 24.04

[dehanj]

Running the packaged tkey-ssh-agent with the systemd unit on Ubuntu 24.04 yields the error

Error while enumerating serial ports: lstat /dev/mqueue: permission denied. 

This is most likely due to changes to what app armor allows, so an app_armor profile is needed.

A workaround with AppArmor enabled is setting kernel.apparmor_restrict_unprivileged_unconfined=0 and kernel.apparmor_restrict_unprivileged_userns=0.
https://ubuntu.com/blog/ubuntu-23-10-restricted-unprivileged-user-namespaces

[durehed]

I had this exact issue and the work around works well.