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

From: Borislav Petkov
Date: Tue Jun 04 2013 - 04:16:10 EST

On Mon, Jun 03, 2013 at 03:54:12PM +0100, Matt Fleming wrote:
> On Mon, 03 Jun, at 03:32:52PM, Matthew Garrett wrote:
> > 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.
> Indeed. That's the approach I took with my 1:1 series from last year. If
> Windows is mapping things at higher addresses like you said, then
> they're probably doing the same.

Right, the way I've done it now is to do the virtual mapping
unconditionally, then do the 1:1 mapping and call SetVirtualAddressMap
(f*cking camelcase is so nasty to type - that's why they need whole IDEs
to program :-)) with that map, if "efi=1:1_map" has been passed on the
cmd line.

After the call, we use *only* the 1:1 map but the virtual mapping is
still there.

The initial approach to addressing the b0rked Macs would then be to
never use the 1:1 map on them.


Sent from a fat crate under my desk. Formatting is fine.
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