Formal virtualization requirements for the ARM architecture

We present an analysis of the virtualizability of the ARMv7-A architecture carried out in the context of the seminal paper published by Popek and Goldberg 38 years ago. Because their definitions are dated, we first extend their machine model to modern architectures with paged virtual memory, IO and interrupts. We then use our new model to show that ARMv7-A is not classically virtualizable.Insights such as binary translation enable efficient virtualization beyond the original criteria. Companies are also making their architectures virtualizable through extensions. We analyse both approaches for ARM and conclude that both have their use in future systems.