OpenBSD-current now runs as guest under Apple Hypervisor (undeadly.org)

Article summary

OpenBSD-current can now run as a guest under Apple Hypervisor, thanks to recent commits that fixed issues with the viogpu driver and added support for the VIRTIO_NET_F_MTU feature. This development allows OpenBSD to work on Apple Virtualization, which is a significant improvement for users with newer Apple Silicon Mac models. The fix also resolves a QEMU compatibility bug that caused OpenBSD to hang when starting X on arm64. Users can now test OpenBSD using snapshots.

Main themes

• OpenBSD on Apple Hypervisor
• Virtualization framework
• QEMU compatibility
• VIRTIO_NET_F_MTU support
• Apple Silicon Mac support

What commenters say

• The development of OpenBSD on Apple Hypervisor is a significant improvement for users with newer Apple Silicon Mac models.
• The VIRTIO_NET_F_MTU negotiation has been a roadblock for many guest OS implementations on Apple's virtualization stack, and OpenBSD's explicit patching of support is a big deal for local development.
• Some users prefer using UTM, a wrapper around qemu and Apple virtualisation, but it is not the same as using the raw hypervisor.
• Implementing system calls in an operating system class is a more realistic and useful assignment than changing how a kernel is loaded to match how Linux does it.
• The fix for QEMU compatibility bug that caused OpenBSD to hang when starting X on arm64 is a significant improvement for users who want to try out OpenBSD.
• A unikernel would probably be even better than an OpenBSD guest for testing pf configurations or running isolated mail servers, but it requires a mail server set up for running as a unikernel without an underlying OS.
• The naming of Apple's virtualization frameworks is confusing and can lead to mixing up Hypervisor.framework and Virtualization.framework.
• OpenBSD's boot process is different from Linux, and changing it to match Linux's boot process is not a trivial task.