Linux/KVM host path: interest in a minimal runnable milestone

[dyxushuai]

I’ve been trying ArcBox in a product context and like the direction a
lot, especially the virt stack. My day-to-day environment is Linux, so
the gap between the in-tree KVM scaffolding and something I can actually
run locally is hard to ignore.

I’d like to spend spare time on the Linux host path. This issue is only M0:

• Get the Linux/KVM hypervisor path building cleanly on the arch I can test.
• Add a basic KVM smoke test (open /dev/kvm, create a VM, fail clearly on permission/API problems).
• Keep PRs small and Linux-gated; no guest boot, TAP/agent, or product integration in this issue.
• Stay off the macOS hot path so this work does not affect current macOS performance.

M0 should stay in this repo (arcbox-hypervisor / vmm Linux bits). Looking
across the org, later steps (not this issue) would likely touch:

• Guest boot: kernel, boot-assets
• Machine / distro images: machine-images, distro
• OCI / rootfs tooling: oci2rootfs, ext4-rs
• Orthogonal Linux microVM SDK: firecracker-client (not assumed for this KVM path)
• KVM CI later: actions or a self-hosted runner (M0 can stay local-only)

Is volunteer work on that M0 slice welcome? Anything I should avoid?

If not, I’ll start with build + smoke and open a small PR referencing this issue.

[pullfrog]

  ^{｜ Build this ➔ ｜ Make a plan ➔}

[linear-code]

ABX-495