Exploiting Virtual Addressing for Increasing Reliability

A novel method to protect a system against errors resulting from soft errors occurring in the virtual address (VA) storing structures such as translation lookaside buffers (TLB), physical register file (PRF) and the program counter (PC) is proposed in this paper. The work is motivated by showing how soft errors impact the structures that store virtual page numbers (VPN). A solution is proposed by employing linear block encoding methods to be used as a virtual addressing scheme at link time. Using the encoding scheme to assign VPNs for VAs, it is shown that the system can tolerate soft errors using software with the help of the discussed decoding techniques applied to the page fault handler. The proposed solution can be used on all of the architectures using virtually indexed addressing. The main contribution of this paper is the decreasing of AVF for data TLB by 42.5%, instruction TLB by 40.3%, PC by 69.2% and PRF by 33.3%.