FAIL*: An Open and Versatile Fault-Injection Framework for the Assessment of Software-Implemented Hardware Fault Tolerance

Due to voltage and structure shrinking, the influence of radiation on a circuit's operation increases, resulting in future hardware designs exhibiting much higher rates of soft errors. Software developers have to cope with these effects to ensure functional safety. However, software-based hardware fault tolerance is a holistic property that is tricky to achieve in practice, potentially impaired by every single design decision. We present FAIL*, an open and versatile architecture-level fault-injection (FI) framework for the continuous assessment and quantification of fault tolerance in an iterative software development process. FAIL* supplies the developer with reusable and composable FI campaigns, advanced pre-and post-processing analyses to easily identify sensitive spots in the software, well-abstracted back-end implementations for several hardware and simulator platforms, and scalability of FI campaigns by providing massive parallelization. We describe FAIL*, its application to the development process of safety-critical software, and the lessons learned from a real-world example.