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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7C26CC433EF for ; Wed, 20 Oct 2021 17:26:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 65A796138B for ; Wed, 20 Oct 2021 17:26:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230355AbhJTR2t (ORCPT ); Wed, 20 Oct 2021 13:28:49 -0400 Received: from mga18.intel.com ([134.134.136.126]:27405 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230031AbhJTR2r (ORCPT ); Wed, 20 Oct 2021 13:28:47 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10143"; a="215763495" X-IronPort-AV: E=Sophos;i="5.87,167,1631602800"; d="scan'208";a="215763495" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Oct 2021 10:26:32 -0700 X-IronPort-AV: E=Sophos;i="5.87,167,1631602800"; d="scan'208";a="720499302" Received: from yakasaka-mobl1.gar.corp.intel.com (HELO skuppusw-desk1.amr.corp.intel.com) ([10.254.9.165]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Oct 2021 10:26:29 -0700 Subject: Re: [PATCH v5 06/16] x86/tdx: Make DMA pages shared To: Tom Lendacky , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Peter Zijlstra , Andy Lutomirski , Bjorn Helgaas , Richard Henderson , Thomas Bogendoerfer , James E J Bottomley , Helge Deller , "David S . Miller" , Arnd Bergmann , Jonathan Corbet , "Michael S . Tsirkin" , Paolo Bonzini , David Hildenbrand , Andrea Arcangeli , Josh Poimboeuf 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, linux-pci@vger.kernel.org, linux-alpha@vger.kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, sparclinux@vger.kernel.org, linux-arch@vger.kernel.org, linux-doc@vger.kernel.org, virtualization@lists.linux-foundation.org References: <20211009003711.1390019-1-sathyanarayanan.kuppuswamy@linux.intel.com> <20211009003711.1390019-7-sathyanarayanan.kuppuswamy@linux.intel.com> <654455db-a605-5069-d652-fe822ae066b0@amd.com> <66acafb6-7659-7d76-0f52-d002cfae9cc8@linux.intel.com> <0b06e686-b0d8-9485-ae00-b23f805916d9@amd.com> From: Sathyanarayanan Kuppuswamy Message-ID: <930ec8e0-669d-8501-af66-38e4cab60a1f@linux.intel.com> Date: Wed, 20 Oct 2021 10:26:29 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Firefox/78.0 Thunderbird/78.13.0 MIME-Version: 1.0 In-Reply-To: <0b06e686-b0d8-9485-ae00-b23f805916d9@amd.com> 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 10/20/21 10:22 AM, Tom Lendacky wrote: >> >> For non TDX case, in CC_ATTR_HOST_MEM_ENCRYPT, we should still call >> amd_force_dma_unencrypted() right? > > What I'm saying is that you wouldn't have amd_force_dma_unencrypted(). I > think the whole force_dma_unencrypted() can exist as-is in a different > file, whether that's cc_platform.c or mem_encrypt_common.c. > > It will return true for an SEV or TDX guest, true for an SME host based > on the DMA mask or else false. That should work just fine for TDX. Got it. Thanks for clarifying it. -- Sathyanarayanan Kuppuswamy Linux Kernel Developer