Re: [PATCH 4/4] x86, efi: Map runtime services 1:1

Borislav Petkov
2013-06-06T19:36:13Z

On Thu, Jun 06, 2013 at 12:28:20PM -0700, H. Peter Anvin wrote:
> Or we could materialize mappings for this specific PGD. However,
> adding a read of %cr3 in __do_page_fault sounds expensive.

Yes, I think we want to make sure all mappings are there when we do an
EFI runtime call so that we never #PF while it executes.

Matt mentioned on IRC that the it could be that his EFI runtime is
referencing EFI_RESERVED area which we don't map. However, we need to
confirm/disprove that first, as it is currently only a hunch.

--
Regards/Gruss,
Boris.

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