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Date:   Thu, 10 Jun 2021 23:07:46 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     "Kuppuswamy, Sathyanarayanan" 
        <sathyanarayanan.kuppuswamy@linux.intel.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Andy Lutomirski <luto@kernel.org>,
        Peter H Anvin <hpa@zytor.com>,
        Dave Hansen <dave.hansen@intel.com>,
        Tony Luck <tony.luck@intel.com>,
        Dan Williams <dan.j.williams@intel.com>,
        Andi Kleen <ak@linux.intel.com>,
        Kirill Shutemov <kirill.shutemov@linux.intel.com>,
        Kuppuswamy Sathyanarayanan <knsathya@kernel.org>,
        Sean Christopherson <seanjc@google.com>,
        linux-kernel@vger.kernel.org, x86@kernel.org
Subject: Re: [PATCH v1 04/11] x86/x86: Add is_tdx_guest() interface
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On Thu, Jun 10, 2021 at 02:01:41PM -0700, Kuppuswamy, Sathyanarayanan wrote:
> Is it alright to use vendor name in prot_guest_has() flag? I thought
> we want to keep them generic.

Sure but keeping them only generic doesn't work in cases like this.

And just like you have:

+/* Protected Guest Feature Flags (leave 0-0xff for arch specific flags) */

there could be ranges for vendor-specific flags.

Intel at 200-2ff
AMD   at 300-3ff

which is 256 per vendor, so should be enough. :)

-- 
Regards/Gruss,
    Boris.

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