A framework for low overhead hardware based runtime control flow error detection and recovery

Transient errors during execution of a process running on a processor can lead to serious system failures or security lapses. It is necessary to detect, and if possible, correct these errors before any damage is caused to the system. Of the many approaches, monitoring the control flow of an application during runtime is one of the techniques used for transient error detection during an application execution. Although promising, the cost of implementing the control flow checks in software has been prohibitively high and hence is not widely used in practice. In this paper we describe a hardware based control flow monitoring technique which has the capability to detect errors in control flow and the instruction stream being executed on a processor. Our technique achieves a high coverage of control flow error detection (99.98 %) and has the capability to quickly recover from the error, making it resilient to transient control flow errors. It poses an extremely low performance overhead (~ 1 %) and reasonable area cost (<; 6 %) to the host processor. The framework for runtime monitoring of control flow described in this paper can be extended to efficiently monitor and detect any transient errors in the execution of instructions on a processor.