proposal: allow starting the QEMU gdbserver

[lmb]

It would be nice if it was possible to invoke vmtest like so:

$ vmtest --debug

Which would then proceed to start the qemu GDB server. (Preferably bound to localhost instead of *.) This makes it really easy to debug kernel issues or bugfixes.

[danobi]

Makes sense to me. But rather than over TCP (which would imply bringing up networking), how about orchestrating a serial device that's shared between the host and guest? The gdbserver docs seem to imply that's possible. For kernel gdb server TCP is probably fine (looking at qemu's -s flag)

[lmb]

I only care about the in-qemu GDB server to be able to debug the kernel, I wasn't aware that it's possible to start one in the guest as well!

[danobi]

Ah ok, let's start with kernel gdb server first. Should be a neat feature.