On 11/29/21 19:23, Sean Christopherson wrote:
Only one generation of CPU, Nehalem, supports EPT but not
unrestricted guest, and disabling unrestricted guest without also
disabling EPT is, to put it bluntly, dumb.
This one is only significantly better and lacks an explanation what this
means for the dumb case.
Well, it means a retpoline (see paragraph before).
No, the point being made is that, on a CPU that supports Unrestricted Guest (UG),
disabling UG without disabling EPT is really, really stupid.
Yes, I understand that.
Thomas was asking what it means to "Move register caching logic to
common code", i.e. what the consequences are. The missing words at the
end of the first paragraph didn't make the connection obvious between
the extra retpoline and the "dumb case".
Paolo
