"It's also worth noting that OpenBSD's developers decided to disable SMT by default in their kernel scheduler last year after a different vulnerability related to CPU buffers was disclosed. "Since many modern machines no longer provide the ability to disable hyper-threading in the BIOS setup, [we] provide a way to disable the use of additional processor threads in our scheduler," the OpenBSD developers said at the time. "And since we suspect there are serious risks, we disable them by default."" https://www.csoonline.com/article/3395458/the-second-meltdown-new-intel-cpu-attacks-leak-secrets.html