Ubuntu subiquity crashes on Tart using same exact autoinstall user-data cloud-init as works on x86_64

[HariSekhon]

I expect this is a subiquity bug more than a Tart problem so have raised it here with full details:

https://bugs.launchpad.net/ubuntu/+source/subiquity/+bug/2022856

but raising this here in case anybody has seen similar issues.

Also, I wanted to try a workaround of running a simple local webserver to serve the user-data and pointing the Ubuntu installer to use the use-data over the network instead of from a local cdrom iso, to see if I can isolate the difference from my working x86_64 build if this is an installer code path issue or an ARM code path or even a Tart related issue.

However, the installer hits the exact same error.

I had used tty2 to determine the IP and gateway, ran a python3 -m http.server on the Mac and did a curl http://192.168.64.1:8000/user-data to check that it worked.

You can reproduce using the network autoinstall user data via this command:

make ubuntu-tart-http

which will start the python web server and then run the alternate http autoinstall configuration to show this.