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 A9C7CECAAD5 for ; Sun, 28 Aug 2022 20:14:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229557AbiH1UO2 (ORCPT ); Sun, 28 Aug 2022 16:14:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47582 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229507AbiH1UO1 (ORCPT ); Sun, 28 Aug 2022 16:14:27 -0400 Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 93D4A11C07; Sun, 28 Aug 2022 13:14:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1661717666; x=1693253666; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=rO3IvTkqA5van28FZL0bDHUA5WA49U4FvaK1jBtX1vk=; b=IVS1AYDyet41iEV4vf6oeg8OM5W9kN3JKXMFEyQkM3XD1oupZ+sHMA8k FqABGj9PqDEdbSh385HRshVUD0pCWMxoEAUCvqfmo9NvPxBhk5Ka7gaux J6KokyP++Y5YccJcwJ8kLAp8GtuYyy17me8ag4bZjFaCqVTd68+raZL1e fiQhC0blogfNwxnSs5qE7TnJS70VzFaNmX1QWjTmRDkdKJyUgwkH3J9UT bW85SEjO8CQDSbHcP8boVeFUD1jDDv68/lzhnwzZBfW++yH0UDVCCNJMm /wxpSVF+Q8ATSK4jRNC6e5nTDVKHX3uW2D6dzexyLFlTtbGAh3gTpN6Xy A==; X-IronPort-AV: E=McAfee;i="6500,9779,10453"; a="281735123" X-IronPort-AV: E=Sophos;i="5.93,271,1654585200"; d="scan'208";a="281735123" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Aug 2022 13:14:25 -0700 X-IronPort-AV: E=Sophos;i="5.93,271,1654585200"; d="scan'208";a="672132378" Received: from pranathi-mobl.amr.corp.intel.com (HELO [10.209.82.24]) ([10.209.82.24]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Aug 2022 13:14:24 -0700 Message-ID: Date: Sun, 28 Aug 2022 13:14:24 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.11.0 Subject: Re: [PATCH v11 1/3] x86/tdx: Add TDX Guest attestation interface driver Content-Language: en-US To: Kuppuswamy Sathyanarayanan , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Shuah Khan Cc: "H . Peter Anvin" , Greg Kroah-Hartman , "Kirill A . Shutemov" , Tony Luck , Andi Kleen , Kai Huang , Wander Lairson Costa , Isaku Yamahata , marcelo.cerri@canonical.com, tim.gardner@canonical.com, khalid.elmously@canonical.com, philip.cox@canonical.com, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-doc@vger.kernel.org References: <20220826150638.2397576-1-sathyanarayanan.kuppuswamy@linux.intel.com> From: Dave Hansen In-Reply-To: <20220826150638.2397576-1-sathyanarayanan.kuppuswamy@linux.intel.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org On 8/26/22 08:06, Kuppuswamy Sathyanarayanan wrote: > +struct tdx_report_req { > + __u8 subtype; > + __u64 reportdata; > + __u32 rpd_len; > + __u64 tdreport; > + __u32 tdr_len; > +}; Please do take a look at how the compiler ends up building that structure. If you sized things to "save space", the way the compiler treats that structure may surprise you. You might also want to look at how a 32-bit compile deals with it versus a 64-bit one.