Re: [RFC Part1 PATCH v3 05/17] x86, realmode: Don't decrypt trampoline area under SEV

Borislav Petkov
2017-07-26T16:03:04Z

Subject: x86/realmode: ...

On Mon, Jul 24, 2017 at 02:07:45PM -0500, Brijesh Singh wrote:
> From: Tom Lendacky <thomas.lendacky-5C7GfCeVMHo@public.gmane.org>
>
> When SEV is active the trampoline area will need to be in encrypted
> memory so only mark the area decrypted if SME is active.
>
> Signed-off-by: Tom Lendacky <thomas.lendacky-5C7GfCeVMHo@public.gmane.org>
> Signed-off-by: Brijesh Singh <brijesh.singh-5C7GfCeVMHo@public.gmane.org>
> ---
> arch/x86/realmode/init.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/realmode/init.c b/arch/x86/realmode/init.c
> index 1f71980..c7eeca7 100644
> --- a/arch/x86/realmode/init.c
> +++ b/arch/x86/realmode/init.c
> @@ -63,9 +63,11 @@ static void __init setup_real_mode(void)
> /*
> * If SME is active, the trampoline area will need to be in
> * decrypted memory in order to bring up other processors
> - * successfully.
> + * successfully. For SEV the trampoline area needs to be in
> + * encrypted memory, so only do this for SME.

Or simply say:

"It is not needed for SEV."

--
Regards/Gruss,
Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
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