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Date:   Mon, 24 Oct 2022 11:35:36 -0500
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Subject: Re: [PATCH] KVM: SVM: Fix reserved fields of struct sev_es_save_area
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To:     Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>
Cc:     tglx@linutronix.de, bp@alien8.de, mingo@redhat.com,
        dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com,
        venu.busireddy@oracle.com, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        "Lendacky, Thomas" <Thomas.Lendacky@amd.com>, bilbao@vt.edu
References: <986a5886-4ddc-aa88-db52-e8781ec95aed@amd.com>
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From:   Carlos Bilbao <carlos.bilbao@amd.com>
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On 10/22/22 02:46, Paolo Bonzini wrote:

> On 10/4/22 18:29, Sean Christopherson wrote:
>> If we really want to the number to have any kind of meaning without 
>> needing a pile
>> of churn for every update, the best idea I can think of is to name 
>> them reserved_<offset>.
>> That way only the affected reserved field needs to be modified when 
>> adding new
>> legal fields.  But that has it's own flavor of maintenance burden as 
>> calculating
>> and verifying the offset is a waste of everyone's time.
>
> Finding the right offsets is usually pretty quick because they can be 
> found in the manual (or something close to the offset can be found 
> there) and verifying them can be done with BUILD_BUG_ON.
>
> If Carlos prepared a patch using offsets (with BUILD_BUG_ON to ensure 
> no future bitrot) I would apply it gladly.  If it's just renumbering 
> as in this one, however, I'd just ignore it.
>
> Paolo
>
> Paolo
>
Sure, I'm sending that.

Thanks,

Carlos