Re: [PATCH v5 06/15] x86/sev: Drop redundant and potentially misleading 'sev_enabled'

From: Borislav Petkov
Date: Thu Apr 22 2021 - 08:20:04 EST


On Wed, Apr 21, 2021 at 07:11:16PM -0700, Sean Christopherson wrote:
> Drop the sev_enabled flag and switch its one user over to sev_active().
> sev_enabled was made redundant with the introduction of sev_status in
> commit b57de6cd1639 ("x86/sev-es: Add SEV-ES Feature Detection").
> sev_enabled and sev_active() are guaranteed to be equivalent, as each is
> true iff 'sev_status & MSR_AMD64_SEV_ENABLED' is true, and are only ever
> written in tandem (ignoring compressed boot's version of sev_status).
>
> Removing sev_enabled avoids confusion over whether it refers to the guest
> or the host, and will also allow KVM to usurp "sev_enabled" for its own
> purposes.
>
> No functional change intended.
>
> Reviewed-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
> Reviewed-by: Brijesh Singh <brijesh.singh@xxxxxxx>
> Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
> ---
> arch/x86/include/asm/mem_encrypt.h | 1 -
> arch/x86/mm/mem_encrypt.c | 12 +++++-------
> arch/x86/mm/mem_encrypt_identity.c | 1 -
> 3 files changed, 5 insertions(+), 9 deletions(-)

Acked-by: Borislav Petkov <bp@xxxxxxx>

Thx.

--
Regards/Gruss,
Boris.

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