A Look At The Big Impact To AES-XTS Encryption Performance From Spectre Retpolines

With it recently being noticed that the Linux AES-NI XTS performance regressed big time from the return trampolines "Retpolines" enacted nearly three years ago as a defense against Spectre, here are some benchmarks looking at the performance cost involved to this day using Retpolines and the impact on the XTS encryption/decryption performance measured by cryptsetup that is used for setting up encrypted disks under Linux...