From mboxrd@z Thu Jan  1 00:00:00 1970
From: Borislav Petkov <bp-l3A5Bk7waGM@public.gmane.org>
Subject: Re: [RFC Part1 PATCH v3 05/17] x86, realmode: Don't decrypt
 trampoline area under SEV
Date: Wed, 26 Jul 2017 18:03:04 +0200
Message-ID: <20170726160304.GE30471@nazgul.tnic>
References: <20170724190757.11278-1-brijesh.singh@amd.com>
 <20170724190757.11278-6-brijesh.singh@amd.com>
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To: Brijesh Singh <brijesh.singh-5C7GfCeVMHo@public.gmane.org>
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 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)
--