001 Host Update Mechanism

Proposed

Spectrum currently has no implementation for software update. The host — consisting of the Linux kernel, KVM, cloud-hypervisor and minimal user space tools — will require software updates to support feature development and security fixes.

The Spectrum installer will set up the system on partition A of the block device, as part of an A/B update scheme where user (or installer) writes the update image to partition B.

The bootloader will provide four boot options: A, A (mutable), B, B (mutable).

Default boot selection, incremental updates (e.g. overlays), and over-the-air updates are postponed for later.