CMRX: Microkernel-based RTOS with memory isolation on MMU-less architectures

Despite memory isolation being used for decades now; a typical contemporary low-power IoT embedded system does not use this technique. One of reasons might be that in virtually all available systems memory isolation is an afterthought. We proposed, designed and implemented CMRX real-time operating system targeted towards devices without MMU which takes memory isolation as non-negotiable feature.

Achieving usable memory isolation on such constrained hardware has its challenges and there are compromises to be made. In this talk I will outline high-level design decisions and overall system design of the CMRX RTOS. Why micro-kernel design is suitable in this situation, what advantages does it bring? I will tackle benefits and potential drawbacks of proposed architecture and finally cybersecurity point of view will be discussed.