Porting bhyve on ARM-based platforms

bhyve was originally developed for x86-based platforms, the kernel code being written in the machine dependant part of the kernel (amd64/vmm). The exposed interface was made to be as generic as posible in order to be usable in the future by other platforms. As a first step I duplicated in arm/vmm the interface exposed in amd64/vmm, eliminating the x86 dependant variables. Than I've implemented the low-level context switch code that saves and restores the state of a virtual machine (arm/vmm/*.S files). ARM offers support only for a Type-1 hypervisor (running without the support of a HostOS). The HostOS doesn't run in the highest priviledge level. At this step we created the concept of "microvisor" which runs in the highest priviledge level (HYP-Mode) and context switches from the Host-OS to the Guest-OS whenever is needed (basically is a bridge between the VMs and the HostOS).

Any virtualization solution needs userspace utilities to control the state of a VM. We have rewritten the bhyve* utilities for ARM (bhyveloadarm and bhyvearm). Until this moment we are able to boot a virtual machine on an ARM platform that supports virtualization extensions (ARMv7e - CortexA15 on FastModels) until the interrupt controller gets initilized. The virtualization of interrupt controller and the timer are work-in-progress at this moment. In the next month we want to finish-up the current work-in-progress to have a fully functional virtual machine running on top of FreeBSD using an ARM processor.

Also in parallel there is a project trying to run bhyvearm on a real hardware platform from ARM: Exynos5250.

The goal of this talk is to give a status report of the whole project (porting bhyve on ARM) and may be a little demo.