Bhyve (FreeBSD's native hypervisor) already contains a 9P over VirtIO "server". The protocols allows virtual machines and their host to share a directory instea

Bhyve (FreeBSD's native hypervisor) already contains a 9P over VirtIO "server". The protocols allows virtual machines and their host to share a directory instead of block storage without having to configure and use a network filesystem like NFS. It's even bootable as in the UEFI BootROM should be able to read the bootloader via 9P, the bootloader can use EFI boot services to read the kernel (configuration, kernel image, kernel modules), and the kernel can than mount it as root filesystem. This means that use a directory instead of an image to boot a virtual machine. I can imagine a lot of use-cases for this e.g. a CI/CD pipeline that tests an experimental kernel (feature) inside a hypervisor.