Software-Based Fault Recovery via Adaptive Diversity for COTS Multi-Core Processors

The ever growing demands of embedded systems to satisfy high computing performance and cost efficiency lead to the trend of using commercial off-the-shelf hardware. However, due to their highly integrated design they are becoming increasingly susceptible to hardware errors (e.g. caused by radiation-induced soft-errors or wear-out effects). Since such faults cannot be fully prevented, systems have to cope with their effects. At the same time there is the trend of multi-core processors in embedded systems. Approaches to achieve fault tolerance by using the multiple cores to establish redundancy have been presented in literature. However, typically only homogeneous redundancy techniques are considered to tolerate soft errors. However, there is a lack of appropriate reaction mechanisms for restoring the system in case of permanent hardware faults. Here, we propose the basic idea of enhancing multi-core redundancy techniques with a cost-efficient automated introduction of diversity in the executed software replicas. Recently, these automated software diversity techniques have attracted attention in the security domain. We propose to use these techniques to recover from permanent hardware faults. This is achieved by adapting the software execution in such a way that permanent faults are mitigated.