Lightweight and Secure Branch Predictors against Spectre Attacks

Spectre attacks endanger most of CPUs, operating systems and cloud services due to the sharing of branch predic- tors in modern processors, while existing defenses fail to balance the security and overhead. This paper designs a lightweight and secure branch predictor (LS-BP), which provides lightweight hardware isolation for different branch entries of same-address- space and cross-address-space. Therefore, it is difficult for the attacker to establish branch conflicts. Experimental results show the average performance overhead is less than 3% while providing strong protection.