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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 94E07C433FE for ; Fri, 4 Mar 2022 15:47:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240512AbiCDPsg (ORCPT ); Fri, 4 Mar 2022 10:48:36 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38844 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229565AbiCDPsd (ORCPT ); Fri, 4 Mar 2022 10:48:33 -0500 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9F1454C793 for ; Fri, 4 Mar 2022 07:47:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1646408865; x=1677944865; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=+DAHh/nBkswlckD+VfCIc7Of9xtKftEyvJuWfkqhNQQ=; b=CEuGFyIITIcCOdXaZlN3m5a2jXL87aUQ2taWgi9NRay+FovlEa9EQ3nm yamUdC4WAEKRfgRi0m1czcL4/LQG/5R1l7EKKDOxWCJ/foU35iFm61ZD1 P2EYD1opsyqyidPKI4T/c1ZX9fpqbYFUggzScpDLfmYEQhioQjbg5CfnR TxSmHcZxK0oc+y6CEWu0OEemXidzdAuK5zqxNxjuu+VMHfNNZ3ocRD27i Hg+NNPs6eav2cVyIkRTIluL4pdKAmuCAqeeMONI7IP8PGvnpPhD48wQUk QqR+i+Fl+fqMgDZJw4sDNoFI+9DD5SNwMqXEOwizN+KhA3K5QON1EWF5E w==; X-IronPort-AV: E=McAfee;i="6200,9189,10276"; a="278691157" X-IronPort-AV: E=Sophos;i="5.90,155,1643702400"; d="scan'208";a="278691157" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Mar 2022 07:47:45 -0800 X-IronPort-AV: E=Sophos;i="5.90,155,1643702400"; d="scan'208";a="640616363" Received: from eabada-mobl2.amr.corp.intel.com (HELO [10.209.6.252]) ([10.209.6.252]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Mar 2022 07:47:44 -0800 Message-ID: <4de457b3-eec9-5415-7e7f-0d5abd4ca08b@intel.com> Date: Fri, 4 Mar 2022 07:47:37 -0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 Subject: Re: [PATCHv5 01/30] x86/tdx: Detect running as a TDX guest in early boot Content-Language: en-US To: Borislav Petkov , "Kirill A. Shutemov" Cc: tglx@linutronix.de, mingo@redhat.com, luto@kernel.org, peterz@infradead.org, sathyanarayanan.kuppuswamy@linux.intel.com, aarcange@redhat.com, ak@linux.intel.com, dan.j.williams@intel.com, david@redhat.com, hpa@zytor.com, jgross@suse.com, jmattson@google.com, joro@8bytes.org, jpoimboe@redhat.com, knsathya@kernel.org, pbonzini@redhat.com, sdeep@vmware.com, seanjc@google.com, tony.luck@intel.com, vkuznets@redhat.com, wanpengli@tencent.com, thomas.lendacky@amd.com, brijesh.singh@amd.com, x86@kernel.org, linux-kernel@vger.kernel.org, Dave Hansen References: <20220302142806.51844-1-kirill.shutemov@linux.intel.com> <20220302142806.51844-2-kirill.shutemov@linux.intel.com> From: Dave Hansen In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 3/4/22 07:43, Borislav Petkov wrote: > On Wed, Mar 02, 2022 at 05:27:37PM +0300, Kirill A. Shutemov wrote: >> +void __init tdx_early_init(void) >> +{ >> + u32 eax, sig[3]; >> + >> + cpuid_count(TDX_CPUID_LEAF_ID, 0, &eax, &sig[0], &sig[2], &sig[1]); >> + >> + BUILD_BUG_ON(sizeof(sig) != sizeof(TDX_IDENT) - 1); > That's new. > > Is that pure paranoia or what are you protecting here against? Pure reviewer paranoia. :) https://lore.kernel.org/all/YhN5edJQ+LkVc0us@grain/