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 X-Spam-Level: X-Spam-Status: No, score=-10.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AE510C48BDF for ; Fri, 18 Jun 2021 19:14:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8751C610CD for ; Fri, 18 Jun 2021 19:14:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234863AbhFRTQd (ORCPT ); Fri, 18 Jun 2021 15:16:33 -0400 Received: from mga12.intel.com ([192.55.52.136]:56334 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234373AbhFRTQa (ORCPT ); Fri, 18 Jun 2021 15:16:30 -0400 IronPort-SDR: lHar69czcFMeiP9jkBKeEu3a5gF4nagOIjuX2eXfNUnbztRu256lzRMaxsRqSi6ufB1RhqM69v GaMVXbU+mDuA== X-IronPort-AV: E=McAfee;i="6200,9189,10019"; a="186300890" X-IronPort-AV: E=Sophos;i="5.83,284,1616482800"; d="scan'208";a="186300890" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Jun 2021 12:14:19 -0700 IronPort-SDR: PwujYWixwF0gYHwXquNyDtZah+9gdAcwgYWQdqQO0UwRZKMtulYf/G8xtjS3zo6KHK3WMwM0Cv UjklOXyePiUQ== X-IronPort-AV: E=Sophos;i="5.83,284,1616482800"; d="scan'208";a="451496009" Received: from msayeed-mobl.amr.corp.intel.com (HELO skuppusw-mobl5.amr.corp.intel.com) ([10.213.172.5]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Jun 2021 12:14:18 -0700 Subject: Re: [PATCH v2 04/12] x86/x86: Add early_is_tdx_guest() interface To: Borislav Petkov Cc: Thomas Gleixner , Ingo Molnar , Peter Zijlstra , Andy Lutomirski , Peter H Anvin , Dave Hansen , Tony Luck , Dan Williams , Andi Kleen , Kirill Shutemov , Sean Christopherson , Kuppuswamy Sathyanarayanan , x86@kernel.org, linux-kernel@vger.kernel.org References: <20210612210445.2164948-1-sathyanarayanan.kuppuswamy@linux.intel.com> From: "Kuppuswamy, Sathyanarayanan" Message-ID: <76e177b6-7666-bc8f-a00a-c6206578d566@linux.intel.com> Date: Fri, 18 Jun 2021 12:14:16 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.1 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 6/17/21 10:05 AM, Borislav Petkov wrote: > On Sat, Jun 12, 2021 at 02:04:45PM -0700, Kuppuswamy Sathyanarayanan wrote: > >> Subject: Re: [PATCH v2 04/12] x86/x86: Add early_is_tdx_guest() interface > > Subject prefix should be "x86/tdx:" ofc. I will fix this in next version. > >> diff --git a/arch/x86/boot/compressed/tdx.c b/arch/x86/boot/compressed/tdx.c >> new file mode 100644 >> index 000000000000..ddfa4a6d1939 >> --- /dev/null >> +++ b/arch/x86/boot/compressed/tdx.c >> @@ -0,0 +1,28 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +/* >> + * tdx.c - Early boot code for TDX >> + */ >> + >> +#include > > Please no kernel proper includes in the decompressor stage - that thing > is an include hell mess and needs cleaning up. Use cpuid_count() from > arch/x86/boot/cpuflags.c by exporting it properly and add the other > defines here instead of using kernel proper facilities. > > I know, I know, there is other misuse but it has to stop. I will re-use cpuid_count() from cpuflags.c. But it is missing definition for cpuid_eax(0). So, I will have to define a new function to handle it. Hope its alright with you. > >> +static int __ro_after_init tdx_guest = -1; >> + >> +static inline bool native_cpuid_has_tdx_guest(void) > > Why is this function prefixed with "native_"? > >> +{ >> + u32 eax = TDX_CPUID_LEAF_ID, sig[3] = {0}; >> + >> + if (native_cpuid_eax(0) < TDX_CPUID_LEAF_ID) >> + return false; >> + >> + native_cpuid(&eax, &sig[0], &sig[1], &sig[2]); >> + >> + return !memcmp("IntelTDX ", sig, 12); >> +} >> + >> +bool early_is_tdx_guest(void) > > So I guess this is going to be used somewhere, because I don't see it. > Or is it going away in favor of prot_guest_has(PR_GUEST_TDX) ? It is used for handling TDX specific I/O support in decompressor code. You can find its usage in https://lore.kernel.org/patchwork/patch/1444186/ May be I should move this patch next to that patch for easy reading. > > This is the problem with sending new versions of patches as a reply to > the old ones in the patchset: I get confused. Why don't you wait until > the whole thing has been reviewed and then send a new revision which has > all the changes and I can find my way in the context? > > And with the amount of changes so far, you should probably send a new > revision of the initial support set now-ish instead of me reviewing this > one 'til the end. I will send the new series with review fixes. Also, since this patch is only used by I/O support code, I will move this patch to another TDX series which adds TDX I/O support. > > Thx. > -- Sathyanarayanan Kuppuswamy Linux Kernel Developer