Thanks to
@yukaYureka inter-VM networking in #SpectrumOS is now entirely in userspace — the host kernel networking stack is not involved, to the point I think we could just build it with CONFIG_INET=n. Packets are forwarded between application VMs and a VM running the network drivers. This is done with a routing daemon that all the VMs connect to via vhost-user, and an XDP program in the driver VM that forwards packets between a hardware network interface and the virtio-net device from the router.
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