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=-5.3 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 91A85C433B4 for ; Tue, 11 May 2021 00:57:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6DE4D6161C for ; Tue, 11 May 2021 00:57:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230018AbhEKA6G (ORCPT ); Mon, 10 May 2021 20:58:06 -0400 Received: from mga12.intel.com ([192.55.52.136]:41091 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229628AbhEKA6F (ORCPT ); Mon, 10 May 2021 20:58:05 -0400 IronPort-SDR: lqu/X6UteCN/t1XqVWaCN3x8EGa1HBXem+blhnWQ/o9GGkwDjOsJeTrqErGiQJrBcC6Etshjil dAfNmdXrtcbQ== X-IronPort-AV: E=McAfee;i="6200,9189,9980"; a="178914936" X-IronPort-AV: E=Sophos;i="5.82,290,1613462400"; d="scan'208";a="178914936" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 May 2021 17:57:00 -0700 IronPort-SDR: WUv2E4eXYfwDyhrA/lvKTldiswLPuB87I6iCKNz96u+SrTOd2+mtfQJaca3kHBuYv6U3/iyKw2 Ey5mSQRLZDow== X-IronPort-AV: E=Sophos;i="5.82,290,1613462400"; d="scan'208";a="609297151" Received: from kcmorris-mobl1.amr.corp.intel.com (HELO skuppusw-mobl5.amr.corp.intel.com) ([10.213.165.53]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 May 2021 17:56:59 -0700 Subject: Re: [RFC v2 14/32] x86/tdx: Handle port I/O To: Dan Williams , Andi Kleen Cc: Peter Zijlstra , Andy Lutomirski , Dave Hansen , Tony Luck , Kirill Shutemov , Kuppuswamy Sathyanarayanan , Raj Ashok , Sean Christopherson , Linux Kernel Mailing List References: <0e7e94d1ee4bae49dfd0dd441dc4f2ab6df76668.1619458733.git.sathyanarayanan.kuppuswamy@linux.intel.com> From: "Kuppuswamy, Sathyanarayanan" Message-ID: <648fe68f-c521-dbba-4495-9a4d0498a3be@linux.intel.com> Date: Mon, 10 May 2021 17:56:57 -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 5/10/21 4:34 PM, Dan Williams wrote: >>> Surely there's an existing macro for this pattern? Would >>> PUSH_AND_CLEAR_REGS + POP_REGS be suitable? Besides code sharing it >>> would eliminate clearing of %r8. >> >> There used to be SAVE_ALL/SAVE_REGS, but they have been all removed in >> some past refactorings. > Not a huge deal, but at a minimum it seems a generic construct that > deserves to be declared centrally rather than tdx-guest-port-io local. I can define SAVE_ALL_REGS/RESTORE_ALL_REGS. Do you want to move it outside TDX code? I don't know if there will be other users for it? -- Sathyanarayanan Kuppuswamy Linux Kernel Developer