Re: [PATCH 0/4] EFI 1:1 mapping

Matthew Garrett
2013-06-03T14:32:52Z

On Mon, Jun 03, 2013 at 10:11:48AM +0200, Borislav Petkov wrote:
> On Sun, Jun 02, 2013 at 11:56:20PM +0100, Matthew Garrett wrote:
> > I've just run Windows 8 under a hacked up copy of OVMF that dumps
> > the data passed to SetVirtualAddressMap. It seems that Windows *is*
> > mapping the runtime services to higher addresses - so presumably the
> > 1:1 mapping is in addition to the virtual mapping.
>
> But but, once we call SetVirtualAddressMap with the set of addresses of
> the runtime services, only those can be used after, right? If so, we
> can't have both (this is at least my understanding)...

We can only pass one set of addresses to SetVirtualAddressMap(), but it
doesn't seem like there's any intrinsic reason we can't the runtime
regions mapped to multiple virtual addresses.

--
Matthew Garrett | mjg59@srcf.ucam.org