It appears that Intel’s Skylake and Kaby Lake Processors have a flaw while handling some Hyperthreaded instruction loops.
The Debian Mailing List advisory, posted by Henrique Holschuh, relates to processor microcode that contains a defect which, when triggered, could cause unpredictable system behavior, resulting in potential data corruption and loss.
The official statement from Debian’s post is as follows:
“This warning advisory is relevant for users of systems with the Intel
processors code-named “Skylake” and “Kaby Lake”. These are: the 6th and
7th generation Intel Core processors (desktop, embedded, mobile and
HEDT), their related server processors (such as Xeon v5 and Xeon v6), as
well as select Intel Pentium processor models.
TL;DR: unfixed Skylake and Kaby Lake processors could, in some
situations, dangerously misbehave when hyper-threading is enabled.
Disable hyper-threading immediately in BIOS/UEFI to work around the
problem. Read this advisory for instructions about an Intel-provided
The defect is described as happening when processing short loops of less than 64 instructions that use certain registers.
This problem can affect any operating system, the post hints at some workarounds until a microcode fix is introduced through BIOS updates, the main one being to turn off Hyperthreading in the BIOS.
As always it is recommended to have a good backup of any important data, which should be done before any attempts at correcting the issue as and when BIOS updates arrive. If in doubt consult a professional.
For more information regarding the issue, you can access the original post here – Debian post.