4.1. KGDB ARM
TODO: we would need a second serial for KGDB to work, but it is not currently supported on arm and aarch64 with -M virt that we use: https://unix.stackexchange.com/questions/479085/can-qemu-m-virt-on-arm-aarch64-have-multiple-serial-ttys-like-such-as-pl011-t/479340#479340
One possible workaround for this would be to use KDB ARM.
Main more generic question: https://stackoverflow.com/questions/14155577/how-to-use-kgdb-on-arm