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 62A15C433EF for ; Mon, 21 Feb 2022 11:37:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356509AbiBULh6 (ORCPT ); Mon, 21 Feb 2022 06:37:58 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:57362 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231761AbiBULh4 (ORCPT ); Mon, 21 Feb 2022 06:37:56 -0500 Received: from mail-lj1-x233.google.com (mail-lj1-x233.google.com [IPv6:2a00:1450:4864:20::233]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E09651AD98 for ; Mon, 21 Feb 2022 03:37:32 -0800 (PST) Received: by mail-lj1-x233.google.com with SMTP id e8so6243374ljj.2 for ; Mon, 21 Feb 2022 03:37:32 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=7bcBxxLvB8a1gVwhcGni5GvVkzOKi4tvu2bJMKdqE90=; b=Q2SAOB0ZREJE0qo/SdMw4x0BGmiyIo4ZMbg7gVev3Jzn4Y+n9TNBaITUIGJzNzXosD RoGnQkXHAIqji9mrejxuCSNksbV0OZuNlTHXPnn37NpXBHLPp9qiRktZt113kdbS49Z/ Aim0ieQHUnDmK/sCuOhHgKLkoL++tcbcsPobDEX8oUTe6LC1afmn13dzcSru+iapnk6h 9pYaud0gig8KmV+cLguuFvL8mAsdQejnrtWZkBX2gRBXuOYU3DF2JX1TNa/ujrXeCKRL UImL6FybvrrFdeWztnwkthtQyqaaLOiD4H1zxk43gZo4mJ7VykDLTxo5LCs2EoMDvQV4 aZYg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=7bcBxxLvB8a1gVwhcGni5GvVkzOKi4tvu2bJMKdqE90=; b=dtT/kQf1se1BLvUuDWXFk4J8O0em/R+2O0R01+s9c47FuH09oG7COFj+FS9wCGT4vS VfHEZHuiGpjCGSYbrCBCQfu/2gclI2buJTDWknj0BwYzV/6uCiIjHqcF6+2AeKpDq0SA NvzLCV1gOl2e8EEi5Yvicj99dveE4dwjhBnqCj+1DLMDdqhP9TL0K+M9Oz9tK+QrdRT7 eWQgaCgj5R3G9YUGEt+Ih6g5JMC0WylS1Or5kCUehopLbqXfFTgtfDsRKFTa1I+VFCSe yBY7pqFmccsqCI5wNVrc6itc1MKHGvaUHGPk4Uio2WQICjjuSZVY2sixhZO3hpOsCuDC DBsw== X-Gm-Message-State: AOAM530/I1gVk1mxHjZx0TUeXz+Ms10PZ0grD6+DDvX9LNfmDLXQ24zx e23gyDMo6Tk84sFXuHQzo7Q= X-Google-Smtp-Source: ABdhPJx6QMCTVPlgNuDZunl1YOP2ccaC02UF2+Ahd7ddv93HdGlWRZ5YeCmdJr2YU6mRkRUXImcm2g== X-Received: by 2002:a2e:9c94:0:b0:244:4ec3:3313 with SMTP id x20-20020a2e9c94000000b002444ec33313mr14180060lji.281.1645443451135; Mon, 21 Feb 2022 03:37:31 -0800 (PST) Received: from grain.localdomain ([5.18.251.97]) by smtp.gmail.com with ESMTPSA id a22sm1092533lfr.24.2022.02.21.03.37.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Feb 2022 03:37:30 -0800 (PST) Received: by grain.localdomain (Postfix, from userid 1000) id 79E005A0020; Mon, 21 Feb 2022 14:37:29 +0300 (MSK) Date: Mon, 21 Feb 2022 14:37:29 +0300 From: Cyrill Gorcunov To: "Kirill A. Shutemov" Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@intel.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, x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCHv3 13/32] x86/tdx: Detect TDX at early kernel decompression time Message-ID: References: <20220218161718.67148-1-kirill.shutemov@linux.intel.com> <20220218161718.67148-14-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220218161718.67148-14-kirill.shutemov@linux.intel.com> User-Agent: Mutt/2.1.5 (2021-12-30) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 18, 2022 at 07:16:59PM +0300, Kirill A. Shutemov wrote: ... > > + > +void early_tdx_detect(void) > +{ > + u32 eax, sig[3]; > + > + cpuid_count(TDX_CPUID_LEAF_ID, 0, &eax, &sig[0], &sig[2], &sig[1]); > + > + if (memcmp(TDX_IDENT, sig, 12)) > + return; Maybe worth to guard ourself, like BUILD_BUG_ON(sizeof(sig) != (sizeof(TDX_IDENT)-1)); if (memcmp(TDX_IDENT, sig, sizeof(sig)) return;