Hyperthreading flaw discovered in Kaby and Skylake

Just came across this.
I guess this is why it's good to read the Debian Mailing List even if you don't use Debian.

One sharp eyed OCaml developer noticed a glitch in short loops of less than 64 instructions affecting Hyperthreading on Kabylake and Skylake CPU's.

Mitigation:

Disable Hyperthreading

Fix:

Install the relevant microcode or BIOS update.

Juicy Details:

https://lists.debian.org/debian-devel/2017/06/msg00308.html

Somewhat TLDR:

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Scabby lake. Sorry, can't help myself.

Is this bug caused by some other update? Or just a rare occurrence? Seems like the parts have been around long enough this would have been found sooner.

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AMD is laughing right now... :sunglasses:

Disabling Hyper threading is ridiculous, but necessary if you have issues. Patches to follow

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