Implementation of SIVARM: A Simple VMM for the ARM Architecture

By using Virutal Machine Monitors (VMMs) we can overcome many issues in embedded systems. The performance gain of recent hardware enables the use of VMM even in small embedded systems. We implemented a VMM for the ARM architecture that is the most widely used CPU for embedded systems. We name it SIVARM: a simple VMM for the ARM architecture. Since the VMM executes in privileged mode and its guest OS executes in non-privileged mode, the VMM can catch the execution of sensitive instructions as exceptions and emulate them appropriately. The guest OS can execute in non-privileged mode thanks to the virtual banked registers and the virtual processor mode provided by the VMM. Domains are used to control the access between the guest OS and the VMM. The VMM was implemented for the ARM926EJ-S processor, and can successfully boot the Linux on it.