A Fault Injection System Based on QEMU Simulator and Designed for BIT Software Testing

Abstract

An important step in the development of dependable systems is the validation of their fault tolerance properties. Fault injection has been widely used for this purpose. This paper presents a simulator implemented fault injection and monitoring environment based on the QEMU platform, called BitVaSim, which is targeted for the embedded development boards equipped with PowerPC or ARM processor together with Built-In Test software operating environment.BitVaSim takes advantage of simulation and do no harm or irruption to either the real hardware or the software, in addition, all the simulated parts are reachable so that more fault modes are available to achieve.BitVaSim uses abstract key-value pairs to describe the functional fault modes, and then simulates the hardware board as while as realistic faults incurred by hardware into the simulator, in order to monitor the activation of the faults and their impact on the target system especially the BIT system behavior in detail. Fault injection interfaces are configured to implement failure mode matching and fault conditions triggering to inject faults on demand in simulator runtime.Faults injected by BitVaSim can affect any process running on the target system (including the kernel), and it is possible to inject faults in applications for which the source code is not available.Experimental results are presented to demonstrate the accuracy and potential of BitVaSim in the evaluation of the dependability properties of the complex computer systems and the BIT system.