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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 55975ECDFBB for ; Thu, 19 Jul 2018 00:45:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0A33A2084E for ; Thu, 19 Jul 2018 00:45:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0A33A2084E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730220AbeGSB0E (ORCPT ); Wed, 18 Jul 2018 21:26:04 -0400 Received: from mga11.intel.com ([192.55.52.93]:49672 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729230AbeGSB0E (ORCPT ); Wed, 18 Jul 2018 21:26:04 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 18 Jul 2018 17:45:36 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,371,1526367600"; d="scan'208";a="241418705" Received: from jacob-builder.jf.intel.com (HELO jacob-builder) ([10.7.199.155]) by orsmga005.jf.intel.com with ESMTP; 18 Jul 2018 17:45:30 -0700 Date: Wed, 18 Jul 2018 17:47:02 -0700 From: Jacob Pan To: Jean-Philippe Brucker Cc: Lu Baolu , Joerg Roedel , David Woodhouse , ashok.raj@intel.com, sanjay.k.kumar@intel.com, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, yi.y.sun@intel.com, jacob.jun.pan@intel.com Subject: Re: [PATCH 00/10] iommu/vt-d: Add scalable mode support Message-ID: <20180718174702.31e1c1d6@jacob-builder> In-Reply-To: <07fe2e3f-4f4a-58db-ee2a-2620183d93b2@arm.com> References: <1531723793-14607-1-git-send-email-baolu.lu@linux.intel.com> <07fe2e3f-4f4a-58db-ee2a-2620183d93b2@arm.com> Organization: OTC X-Mailer: Claws Mail 3.13.2 (GTK+ 2.24.30; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 16 Jul 2018 11:51:57 +0100 Jean-Philippe Brucker wrote: > Hi, > > On 16/07/18 07:49, Lu Baolu wrote: > > Intel vt-d rev3.0 [1] introduces a new translation mode called > > 'scalable mode', which enables PASID-granular translations for > > first level, second level, nested and pass-through modes. The > > vt-d scalable mode is the key ingredient to enable Scalable I/O > > Virtualization (Scalable IOV) [2] [3], which allows sharing a > > device in minimal possible granularity (ADI - Assignable Device > > Interface). It also includes all the capabilities required to > > enable Shared Virtual Addressing (SVA). As a result, previous > > Extended Context (ECS) mode is deprecated (no production ever > > implements ECS). > > > > Each scalable mode pasid table entry is 64 bytes in length, with > > fields point to the first level page table and the second level > > page table. The PGTT (Pasid Granular Translation Type) field is > > used by hardware to determine the translation type. > > Looks promising! Since the 2nd level page tables are in the PASID > entry, the hypervisor traps guest accesses to the PASID tables > instead of passing through the whole PASID directory? Are you still > planning to use the VFIO BIND_PASID_TABLE interface in this mode, or > a slightly different one for individual PASIDs? > Since we deprecated ECS mode, there is no need for VT-d to bind guest pasid table in scalable mode. We are planning on adding another flag for bind guest pasid and guest CR3, Perhaps call it VFIO_IOMMU_BIND_GUEST_SVA. > Thanks, > Jean > _______________________________________________ > iommu mailing list > iommu@lists.linux-foundation.org > https://lists.linuxfoundation.org/mailman/listinfo/iommu [Jacob Pan]