Applying virtualization to avionics systems — The integration challenges

Multicore virtualization can offer significant benefits to embedded avionics systems with regard to enabling mixed real-time and guest operating system interoperability, legacy code migration, and hardware consolidation. Virtualization enabled architectures have evolved from a traditional Hypervisor Monolithic Model (VmWare and VirtualLogix), to a Hypervisor Console Guest Monolithic Model (Xen), and now to a High Assurance Microkernel Hypervisor RTOS Model. The ability to consolidate multiple legacy Single Board Computers (SBCs) with various guest operating systems and applications into a multicore, virtualized SBC is a critical enabler to next generation avionics. This paper describes an initial feasibility assessment toward applying the Microkernel Hypervisor RTOS Virtual Machine (VM) architecture to enable virtualization for a representative set of avionics applications requiring multiple guest OS environments. The specific notional configuration included: legacy application execution on a legacy RTOS guest OS in VM1, newer application execution on a more recently released level of RTOS on VM2, safety critical applications execution on an ARINC 653 OS on VM3, Global Information Grid (GIG) applications execution on a Linux guest OS on VM4, and MILS/MLS application execution on a high assurance OS on VM5, all executing on a Microkernel Hypervisor RTOS within a Multicore (X86 or Power PC) with hardware-based virtualization support. The paper identifies the current system design issues, limitations/restrictions, and feasibility of applying representative products in this representative hybrid legacy/next generation environment. The system design challenges identified included: 1.) selection of communication mechanisms and scheduling for mixed operating system environments, 2.) addressing current limitations/restrictions of current vendor products with regard to multicore, 3.) properly scheduling the infrastructure to meet the safety and security requirements, 4.) incorporating extensions for MultiLevel Security (MLS) components for networked GIG and local connectivity, and 5.) consolidating I/O components without compromising safety, security, and redundancy considerations.