Linus Torvalds Growing Frustrated By Buggy Hardware & Theoretical CPU Attacks

Over the past week Linux creator Linus Torvalds has been active on a Linux kernel mailing list thread around avoiding barrier_nospec() in copy_from_user() due to being "overkill and painfully slow." The conversation evolved into low-level discussions over CPU behavior and how to best handle, differing behavior/requirements with new Intel CPUs supporting Linear Address Masking (LAM), and the overall headaches these days around CPU security mitigations...