They're new in general - they first appeared last week and they're
being treated as if they're related to Spectre.  I've yet to see any
kind of official release of them, but that seems to be par for the
course for AMD the more I hunt around for documentation.  It seems
like Suse first released it, and claimed that it disabled branch
prediction, whatever that means (certainly it can't completely disable
it without tanking performance).