replace virtme

[lmb]

ci: replace virtme with vimto

vimto is a lightweight wrapper around qemu with the sole purpose of 
executing Go unit tests. Use it instead of virtme, which has not had a
reliable upstream for a while.

Signed-off-by: Lorenz Bauer <lmb@isovalent.com>

[lmb]

Test runs are suspiciously fast.

[paulcacheux]

Not sure if fully applicable, but https://github.com/arighi/virtme-ng is actually supported, and is gaining traction after an article on LWN. Maybe something to look at if we want to replace virtme

[lmb]

@paulcacheux yeah, I'm aware of virtme-ng! I looked at it a while ago.

Pro:

• Already works
• Support for a variety of kernel sources
• virtiofsd
• gdb support?

Con:

• Dependency on rust for init which makes it more difficult to install.
• Doesn't allow distributing kernels as OCI images

So even if we use virtme-ng we need some wrapper code. vimto is easy to install when you're in the go ecosystem already, and I want to add go specific things like a delve wrapper.

Overall virtme-ng is probably the saner choice. The good news is that we can always rip out vimto if it turns out to be too much of a burden.

[lmb]

Finally managed to get CI green. @ti-mo @dylandreimerink @rgo3 maybe you can give it a spin on your machines to see whether it works? (I know that Robin's nix setup is mysteriously broken.)

[ti-mo]

Awesome, thanks! Left a few nits and lifted the fix to the verifier test to #1367 and merged separately.

Note: you signed the middle commit with both emails.

We should also talk about vimto, who's going to develop and maintain it, and how we're going to organize it. It would be worth growing its userbase so more projects can benefit and contribute. Something to be discussed at the Cilium dev summit.

[lmb]

Current status is that vimto needs a bit more thinking. @ti-mo how about I upstream the non-CI changes so that I can use vimto on my machine to test? Currently stranded without a viable virtme and the changes themselves are useful either way I think.

[dylandreimerink]

LGTM overall, just one thing I noticed

[lmb]

Any concerns around merging this? It's at least as useable as virtme from my side.

[dylandreimerink]

I had some issues running vimto locally initially. When I ran the command from the updated index.md to run vimto locally vimto -- go test ./... it fails with a lot of Error: exec: binary is not statically linked (did you build with CGO_ENABLED=0?) errors.
Turns out its because I didn't add CGO_ENABLED=0 when installing vimto itself go install lmb.io/vimto@latest. Adding so is very unusual. It would be nice if we can look into not requiring this. Or else add warnings in docs. Because I think more people will hit this.

Other than that, everything seems to be working! I say merge