On Thu, Jul 9, 2020 at 8:56 AM Dave Hansen <dave.hansen@xxxxxxxxx> wrote: > > On 7/9/20 8:44 AM, Andersen, John wrote: > > > > Bits which are allowed to be pinned default to WP for CR0 and SMEP, > > SMAP, and UMIP for CR4. > > I think it also makes sense to have FSGSBASE in this set. > > I know it hasn't been tested, but I think we should do the legwork to > test it. If not in this set, can we agree that it's a logical next step? I have no objection to pinning FSGSBASE, but is there a clear description of the threat model that this whole series is meant to address? The idea is to provide a degree of protection against an attacker who is able to convince a guest kernel to write something inappropriate to CR4, right? How realistic is this?
