How to Implement a software-based SMEP(Supervisor Mode Execution Protection) with Virtualization/Hypervisor Technology

As my previous post indicated, SMEP is a powerful security feature, and easy to deploy in modern commodity OS. However this feature requires H/W processor's support, for those processors that are not SMEP-capable, this post presents a software-based solution to emulate SMEP functionality with the help of Virtualization/Hypervisor technology. 

Introduction to Processor Hardware Security Features in x86 & ARM Architectures

x86 and ARM processors both provide many hardware enforced security features, e.g. NX (No-eXecute) for executable space protection, to help system software engineers to build a secure computing environment. 

This article summaries those security features for both x86/Intel and ARM architectures, and explains how are they used by Operating System.