This may answer your question:
from FReeper swordmaker’s post #64:
Mitigations by Linux code-base maintainers are underway, as are changes by Microsoft to protect Windows users. In response to a query, Microsoft told AppleInsider that they had no comment on a timetable of a release to fix the security flaw at this time, but kernel memory handling was altered by the company in Windows 10 beta builds in the end of 2017.
“Mitigations by Linux code-base maintainers are underway, as are changes by Microsoft to protect Windows users. In response to a query, Microsoft told AppleInsider that they had no comment on a timetable of a release to fix the security flaw at this time, but kernel memory handling was altered by the company in Windows 10 beta builds in the end of 2017.”
I’m actually pretty sure this does affect Coffee Lake, which is unfortunate as I’m about to build a Coffee Lake system. I’d prefer a switch to turn off the 10-20% performance hit these fixes will entail. Running any kind of malicious code on a desktop system will pretty much expose everything, so this is security theater except on the server side.