Quest-V: A Virtualized Multikernel for High-Confidence Systems

Abstract:

This poster outlines the design of `Quest-V', which is implemented as a collection of separate kernels operating together as a distributed system on a chip. Quest-V uses virtualization techniques to isolate kernels and prevent local faults from affecting remote kernels. This leads to a high-confidence multikernel approach, where failures of system subcomponents do not render the entire system inoperable. A virtual machine monitor for each kernel keeps track of shadow page table mappings that control immutable memory access capabilities. This ensures a level of security and fault tolerance in situations where a service in one kernel fails, or is corrupted by a malicious attack. Communication is supported between kernels using shared memory regions for message passing. Similarly, device driver data structures are shareable between kernels to avoid the need for complex I/O virtualization, or communication with a dedicated kernel responsible for I/O.   In Quest-V, device interrupts can be delivered directly to a kernel, rather than via a monitor that determines the destination. Apart from bootstrapping each kernel, handling faults and managing shadow page tables, the monitors are not needed. This differs from conventional virtual machine systems in which a central monitor, or hypervisor, is responsible for scheduling and management of host resources amongst a set of guest kernels. In this poster, we show how Quest-V can implement novel fault isolation and recovery techniques that are not possible with conventional systems. 

Biography:

Dr. Richard West is an Associate Professor of Computer Science at Boston University. His research interests encompass operating systems, real-time/embedded systems, resource management, kernels, system organization and structure, and hardware-software interaction. His current research focus is on the development of a new operating system, called Quest, and its sister system called Quest-V. While Quest is a real-time OS for multicore systems, Quest-V uses virtualization techniques to implement a safe and predictable OS as a distributed system on a chip. Work on these systems is funded in part by NSF grants, amongst others.

For the past few years, Dr. West has collaborated with VMware, Inc. in both Palo Alto and Cambridge, MA, where he has held the position of Advanced Research Engineer. Through this role, he worked with VMware’s resource management team to develop new performance-enhanced techniques for managing physical resources in the ESX hypervisor. Several patent submissions related to cache-aware resource management and scheduling in multicore systems have since been submitted.

Before joining Boston University, Dr. West obtained Ph.D. and M.S. degrees in Computer Science from the Georgia Institute of Technology. He also holds a Master of Engineering degree from the University of Newcastle-upon-Tyne, England.