From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CC697C433EF for ; Tue, 5 Oct 2021 14:48:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B1B3A6128A for ; Tue, 5 Oct 2021 14:48:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235466AbhJEOu2 (ORCPT ); Tue, 5 Oct 2021 10:50:28 -0400 Received: from mga01.intel.com ([192.55.52.88]:4380 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235322AbhJEOu0 (ORCPT ); Tue, 5 Oct 2021 10:50:26 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10128"; a="249022710" X-IronPort-AV: E=Sophos;i="5.85,349,1624345200"; d="scan'208";a="249022710" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Oct 2021 07:48:30 -0700 X-IronPort-AV: E=Sophos;i="5.85,349,1624345200"; d="scan'208";a="656587448" Received: from cthurman-mobl.amr.corp.intel.com (HELO skuppusw-mobl5.amr.corp.intel.com) ([10.209.18.154]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Oct 2021 07:48:27 -0700 Subject: Re: [PATCH v8 02/11] x86/tdx: Introduce INTEL_TDX_GUEST config option To: Borislav Petkov , Sathyanarayanan Kuppuswamy Natarajan Cc: Randy Dunlap , Thomas Gleixner , Ingo Molnar , x86@kernel.org, Paolo Bonzini , David Hildenbrand , Andrea Arcangeli , Josh Poimboeuf , Juergen Gross , Deep Shah , VMware Inc , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Peter H Anvin , Dave Hansen , Tony Luck , Dan Williams , Andi Kleen , Kirill Shutemov , Sean Christopherson , Linux Kernel Mailing List References: <20211005025205.1784480-1-sathyanarayanan.kuppuswamy@linux.intel.com> <20211005025205.1784480-3-sathyanarayanan.kuppuswamy@linux.intel.com> From: "Kuppuswamy, Sathyanarayanan" Message-ID: Date: Tue, 5 Oct 2021 07:48:25 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Firefox/78.0 Thunderbird/78.13.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/5/21 7:13 AM, Borislav Petkov wrote: > On Tue, Oct 05, 2021 at 06:29:43AM -0700, Sathyanarayanan Kuppuswamy Natarajan wrote: >> For the TDX guest, x2apic will be emulated. So it will exist in our >> case. Even if x2apic or TDX guest is not supported by CPU, it will >> boot just fine. > > Sure but why is it "select" and not "depends"? > > Why does X86_X2APIC need to be selected while the others are "depends"? Since x2APIC will always exist in TDX guest case, we have used select to enable the support. But since we have dependency on it, I think "depends" might be a better choice. > -- Sathyanarayanan Kuppuswamy Linux Kernel Developer