Fault injection tools based on Virtual Machines

Transient and permanent faults in complex digital systems used for safety-critical applications may result in catastrophic effects. It becomes therefore extremely important to adopt techniques such as fault injection to observe the behavior of the system in the presence of faults. Several tools have been proposed in the literature that support fault injection. However, few of them allow observing complex computer-based systems. This paper presents current advances in this field, by focusing on Low Level Virtual Machine (LLVM) based fault injectors and FAUMachine. We give an overview of the LLVM environment, and two based fault injection tools: LLFI and KULFI. Moreover, we introduce FAUmachine as virtual machine that supports fault injection in different components of the system (memory, disk and network). We present limitations and difficulties of the tool, and we propose a new implementation that allows injecting faults into the register of the target processor. The paper concludes with a comparison between the fault injection tools based on virtual machine in a first level, and between the LLVM-based fault injection tools in a second level.