Permanent Fault Injection and Selective Hardening of Real Time Operating Systems

Real-Time Operating Systems (RTOS) are designed to provide deterministic response within predefined time limits. This implies the ability to reliably and predeterminedly manage the flow of events and operations in an electronic system. Real-time Operating Systems are widely used in applications that require strict control of execution time, such as industrial control systems, medical equipment, autonomous vehicles, safety-critical systems and more. However, when the hardware on which the operating system is based is affected by ionizing radiation, such as during cosmic radiation events or failures in high-radiation environments, undesirable, even severe, effects may occur. Therefore, it becomes necessary to adopt a set of mitigation techniques at both the hardware and software levels. Before these mitigation techniques can be applied, it is essential to conduct a thorough analysis of the behavior of real-time operating systems affected by radiation, also using empirical data. For the thesis project, a permanent fault injection model was implemented to simulate the effects that irreversibly damage the electronic system. This model is completely software-based and requires no additional hardware other than that on which the injection environment is run. This offers the advantage of creating a test environment without the need for testing on physical systems. Specifically, the goal of the research is to simulate permanent injections on the data structures of the FreeRTOS real-time operating system (regardless of version) and to develop fault mitigation techniques for that operating system.