Mondriaan Memory Protection

The need for flexible, efficient, fine-grained memory protection and sharing has been neglected in modern computing systems. Mondriaan memory protection (MMP) is a fine-grained protection scheme that allows multiple protection domains to flexibly share memory and export protected services. In contrast to earlier page-based systems, MMP allows arbitrary permissions control at the granularity of individual words. We use a compressed permissions table to reduce space overheads and employ two levels of permissions caching to reduce run-time overheads. We implement the MMP hardware in a simulator and modify a version of the Linux 2.4.19 operating system to use it.