Date:   Tue, 4 Jan 2022 21:57:03 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Sean Christopherson <seanjc@google.com>
Cc:     Brijesh Singh <brijesh.singh@amd.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
        linux-efi@vger.kernel.org, platform-driver-x86@vger.kernel.org,
        linux-coco@lists.linux.dev, linux-mm@kvack.org,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Joerg Roedel <jroedel@suse.de>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        "H. Peter Anvin" <hpa@zytor.com>, Ard Biesheuvel <ardb@kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Jim Mattson <jmattson@google.com>,
        Andy Lutomirski <luto@kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Sergio Lopez <slp@redhat.com>, Peter Gonda <pgonda@google.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
        David Rientjes <rientjes@google.com>,
        Dov Murik <dovmurik@linux.ibm.com>,
        Tobin Feldman-Fitzthum <tobin@ibm.com>,
        Michael Roth <michael.roth@amd.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        "Kirill A . Shutemov" <kirill@shutemov.name>,
        Andi Kleen <ak@linux.intel.com>,
        "Dr . David Alan Gilbert" <dgilbert@redhat.com>,
        tony.luck@intel.com, marcorr@google.com,
        sathyanarayanan.kuppuswamy@linux.intel.com
Subject: Re: [PATCH v8 22/40] x86/sev: move MSR-based VMGEXITs for CPUID to
 helper
Message-ID: <YdS0n3qLFS6r0ksN@zn.tnic>
References: <20211210154332.11526-1-brijesh.singh@amd.com>
 <20211210154332.11526-23-brijesh.singh@amd.com>
 <Yc4ABL2EbBlwjma5@google.com>
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On Thu, Dec 30, 2021 at 06:52:52PM +0000, Sean Christopherson wrote:
> Having @subfunc, a.k.a. index, in is weird/confusing/fragile because it's not consumed,
> nor is it checked.  Peeking ahead, it looks like all future users pass '0'.  Taking the
> index but dropping it on the floor is asking for future breakage.  Either drop it or
> assert that it's zero.

Yah, just drop it please. 

It can always be added later if needed.

Thx.

-- 
Regards/Gruss,
    Boris.

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