Bao: A Lightweight Static Partitioning Hypervisor for Modern Multi-Core Embedded Systems

Given the increasingly complex and mixed-criticality nature of modern embedded systems, virtualization emerges as a natural solution to achieve strong spatial and temporal isolation. Widely used hypervisors such as KVM and Xen were not designed having embedded constraints and requirements in mind. The static partitioning architecture pioneered by Jailhouse seems to address embedded concerns. However, Jailhouse still depends on Linux to boot and manage its VMs. In this paper, we present the Bao hypervisor, a minimal, standalone and clean-slate implementation of the static partitioning architecture for Armv8 and RISC-V platforms. Preliminary results regarding size, boot, performance, and interrupt latency, show this approach incurs only minimal virtualization overhead. Bao will soon be publicly available, in hopes of engaging both industry and academia on improving Bao’s safety, security, and real-time guarantees.