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Date:   Wed, 13 Oct 2021 16:02:33 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Brijesh Singh <brijesh.singh@amd.com>
Cc:     x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
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        "H. Peter Anvin" <hpa@zytor.com>, Ard Biesheuvel <ardb@kernel.org>,
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Subject: Re: [PATCH v6 07/42] x86/sev: Add support for hypervisor feature
 VMGEXIT
Message-ID: <YWbm+SOMv7AXduWR@zn.tnic>
References: <20211008180453.462291-1-brijesh.singh@amd.com>
 <20211008180453.462291-8-brijesh.singh@amd.com>
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On Fri, Oct 08, 2021 at 01:04:18PM -0500, Brijesh Singh wrote:
> Version 2 of GHCB specification introduced advertisement of a features
> that are supported by the hypervisor. Add support to query the HV
> features on boot.
> 
> Version 2 of GHCB specification adds several new NAEs, most of them are
> optional except the hypervisor feature. Now that hypervisor feature NAE
> is implemented, so bump the GHCB maximum support protocol version.
> 
> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
> ---
>  arch/x86/include/asm/sev-common.h |  3 +++
>  arch/x86/include/asm/sev.h        |  2 +-
>  arch/x86/include/uapi/asm/svm.h   |  2 ++
>  arch/x86/kernel/sev-shared.c      | 30 ++++++++++++++++++++++++++++++
>  4 files changed, 36 insertions(+), 1 deletion(-)

For the next version, when you add those variables, do this too pls:

diff --git a/arch/x86/kernel/sev-shared.c b/arch/x86/kernel/sev-shared.c
index 8ee27d07c1cd..7a2176e0d0ad 100644
--- a/arch/x86/kernel/sev-shared.c
+++ b/arch/x86/kernel/sev-shared.c
@@ -21,10 +21,10 @@
  *
  * GHCB protocol version negotiated with the hypervisor.
  */
-static u16 __ro_after_init ghcb_version;
+static u16 ghcb_version __ro_after_init;
 
 /* Bitmap of SEV features supported by the hypervisor */
-static u64 __ro_after_init sev_hv_features;
+static u64 sev_hv_features __ro_after_init;
 
 static bool __init sev_es_check_cpu_features(void)
 {

I didn't realize this earlier but we put that annotation at the end.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette