In Light Of Spectre BHI, The Performance Impact For Retpolines On Modern Intel CPUs

Made public on Tuesday was BHI / Spectre-BHB as the newest offshoot from Spectre V2. There were Linux patches immediately posted for affected Intel and Arm processors while also making adjustments to AMD CPUs around its Retpoline handling. The VUSec security researchers that discovered BHI are recommending Retpolines be enabled for newer processors even those with hardware mitigations against Spectre V2, but that's that performance cost? Here are some initial benchmarks.