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=-5.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 BA94BC07E9E for ; Thu, 8 Jul 2021 14:07:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9C755613B0 for ; Thu, 8 Jul 2021 14:07:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231928AbhGHOKO (ORCPT ); Thu, 8 Jul 2021 10:10:14 -0400 Received: from mga11.intel.com ([192.55.52.93]:3830 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229592AbhGHOKK (ORCPT ); Thu, 8 Jul 2021 10:10:10 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10038"; a="206494882" X-IronPort-AV: E=Sophos;i="5.84,222,1620716400"; d="scan'208";a="206494882" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Jul 2021 07:07:28 -0700 X-IronPort-AV: E=Sophos;i="5.84,222,1620716400"; d="scan'208";a="492127379" Received: from palgarin-mobl.amr.corp.intel.com (HELO skuppusw-mobl5.amr.corp.intel.com) ([10.212.55.207]) by orsmga001-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Jul 2021 07:07:27 -0700 Subject: Re: [PATCH v2 1/6] x86/tdx: Add TDREPORT TDX Module call support To: Xiaoyao Li , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Peter Zijlstra , Andy Lutomirski , Hans de Goede , Mark Gross , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Cc: 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, platform-driver-x86@vger.kernel.org, bpf@vger.kernel.org, netdev@vger.kernel.org References: <20210707204249.3046665-1-sathyanarayanan.kuppuswamy@linux.intel.com> <20210707204249.3046665-2-sathyanarayanan.kuppuswamy@linux.intel.com> From: "Kuppuswamy, Sathyanarayanan" Message-ID: <46944ac2-4841-7f1d-4f54-ecb477f43d63@linux.intel.com> Date: Thu, 8 Jul 2021 07:07:26 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7/8/21 1:16 AM, Xiaoyao Li wrote: > > Sorry I guess I didn't state it clearly during internal review. > > I suggest something like this > > if (ret != TDCALL_SUCCESS) { >     if (TDCALL_RETURN_CODE(ret) == TDCALL_INVALID_OPERAND) >         return -EINVAL; >     else if (TDCALL_RETURN_CODE(ret) == TDCALL_OPERAND_BUSY) >         return -EBUSY; >     else >         return -EFAULT; //I'm not sure if -EFAULT is proper. > } As per current spec, TDCALL_INVALID_OPERAND, TDCALL_OPERAND_BUSY and 0 are the only possible return values. So I have checked for failure case in if condition and returned success by default. Any reason for specifically checking for success code ? -- Sathyanarayanan Kuppuswamy Linux Kernel Developer