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=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS autolearn=unavailable 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 D283DC282D7 for ; Wed, 30 Jan 2019 22:57:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7A77D2084C for ; Wed, 30 Jan 2019 22:57:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=Mellanox.com header.i=@Mellanox.com header.b="puZzaqq/" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731481AbfA3W5V (ORCPT ); Wed, 30 Jan 2019 17:57:21 -0500 Received: from mail-eopbgr20077.outbound.protection.outlook.com ([40.107.2.77]:27510 "EHLO EUR02-VE1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725817AbfA3W5V (ORCPT ); Wed, 30 Jan 2019 17:57:21 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Mellanox.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=YGk9t9BHNwrMkg6K1npyELZ1MhmCrXCLnJJsKqQBeKg=; b=puZzaqq/ms5QN97muzSoMUrqKtRJqJNpLZb6HtkOZYtVmOYlo9oKH8StPkWw3siVwOZOhCzcr1tzkSHo6ArwhPc2DLCZxHfoMoWiyroVtrKSOeARv6gq5KAMKVGgE0nCoQTo+hV4VCAb+0yn8qa/ijNY7wY/7ihZOvG3mUxypsI= Received: from DBBPR05MB6426.eurprd05.prod.outlook.com (20.179.42.80) by DBBPR05MB6473.eurprd05.prod.outlook.com (20.179.42.215) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1580.17; Wed, 30 Jan 2019 22:33:04 +0000 Received: from DBBPR05MB6426.eurprd05.prod.outlook.com ([fe80::24c2:321d:8b27:ae59]) by DBBPR05MB6426.eurprd05.prod.outlook.com ([fe80::24c2:321d:8b27:ae59%5]) with mapi id 15.20.1580.017; Wed, 30 Jan 2019 22:33:04 +0000 From: Jason Gunthorpe To: Jerome Glisse CC: Logan Gunthorpe , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , Greg Kroah-Hartman , "Rafael J . Wysocki" , Bjorn Helgaas , Christian Koenig , Felix Kuehling , "linux-pci@vger.kernel.org" , "dri-devel@lists.freedesktop.org" , Christoph Hellwig , Marek Szyprowski , Robin Murphy , Joerg Roedel , "iommu@lists.linux-foundation.org" Subject: Re: [RFC PATCH 3/5] mm/vma: add support for peer to peer to device vma Thread-Topic: [RFC PATCH 3/5] mm/vma: add support for peer to peer to device vma Thread-Index: AQHUt/rA/dLikqWEmEaIytHIBNLPlqXGkyOAgAAJwICAAAX+AIAAEreAgAAFCQCAAAk3gIAABX0AgAATFYCAAA25AIAAGRqAgAAykICAANmWgIAAG8YAgAAHLwCAAAROgIAABioAgAADIQCAAAkGAIAAAccAgAAPg4CAAAL1AIAACaCAgAAAtAA= Date: Wed, 30 Jan 2019 22:33:04 +0000 Message-ID: <20190130223258.GB25486@mellanox.com> References: <20190130185652.GB17080@mellanox.com> <20190130192234.GD5061@redhat.com> <20190130193759.GE17080@mellanox.com> <20190130201114.GB17915@mellanox.com> <20190130204332.GF5061@redhat.com> <20190130204954.GI17080@mellanox.com> <20190130214525.GG5061@redhat.com> <20190130215600.GM17080@mellanox.com> <20190130223027.GH5061@redhat.com> In-Reply-To: <20190130223027.GH5061@redhat.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-clientproxiedby: MWHPR08CA0059.namprd08.prod.outlook.com (2603:10b6:300:c0::33) To DBBPR05MB6426.eurprd05.prod.outlook.com (2603:10a6:10:c9::16) authentication-results: spf=none (sender IP is ) smtp.mailfrom=jgg@mellanox.com; x-ms-exchange-messagesentrepresentingtype: 1 x-originating-ip: [174.3.196.123] x-ms-publictraffictype: Email x-microsoft-exchange-diagnostics: 1;DBBPR05MB6473;6:EHp16Jtf0x51zHG5aY/zhYvDQsziogL8F7sSYuJ5A2YVm58AzpD4HBvViVJPYCtcTBumczXN14Fnhs7Ur9u/y7sjyyizPOrgbyHG/gPKWbfU8Bpwobg3H/UmfBbzxVTMs4wLnTrnAKdfxkinCaAi4+t+8BlOSuTbY0XNxweq6cdnj5FaS0+RMgiSyPTWDrTHhBvfIxzIF2hwT99UNqgvsDQr0+HMy0L4Jdp/CsGQAqZuq5MBG3xbFbKWcRWLVCl5O6IZ7aTZLajFA59zHMUW0WQOqw1QykTrN03fGVTvSjyJcsm0Eo5kQzngB1cBQQkhXagokbn9trzu/+PbN64+uuG5MKbLQky74RVPU3plsBR8xj0kDuBzA+FGHlEgrJ2R9AUs05z5x5nhbnZ7OuZyHMbRksZKa+L0AIwG8cLZ6L1VqxnXjmTPhfdElp5g7QcnJmedfh3FztbBBAnTtO16Og==;5:4V2k2nJENH8y65nJ5Gfqvy9D8sB+aCCLlXJ58DoWGQCCnA4HeSpZkv9jbd2ctZE9aS5l7ajzpMPjf0C/LSNguxUNYWZln+nspLQVq9Aeelpd0fU9S/WC8Sv/aTuS44iCNdUHb0ooVckfiZ7MCTn/KCUnivx2ezicFeBFU5hxrC32T6OoKOyojZMitvUVjnfX6hqcE2Ctok0gEuY8TpbIQg==;7:dL1aRu8v4M/v9IY8B3AykK1qCfv9jPWCwUJSrhVAsk6LM2PZw0E5YcaMj3wUj4iiuIwiRRa/6n1KBobPHIWIXengM2m3y56PtsBqtTDQLM1ZhSWCxWjwU8AfotxuX64ZrLWfbEX9Bf87FVvzgX1rxQ== x-ms-office365-filtering-correlation-id: bdc53bcc-6a81-4e41-9bca-08d68702e621 x-ms-office365-filtering-ht: Tenant x-microsoft-antispam: BCL:0;PCL:0;RULEID:(2390118)(7020095)(4652040)(8989299)(4534185)(4627221)(201703031133081)(201702281549075)(8990200)(5600110)(711020)(4605077)(4618075)(2017052603328)(7153060)(7193020);SRVR:DBBPR05MB6473; x-ms-traffictypediagnostic: DBBPR05MB6473: x-microsoft-antispam-prvs: x-forefront-prvs: 0933E9FD8D x-forefront-antispam-report: SFV:NSPM;SFS:(10009020)(346002)(376002)(366004)(136003)(396003)(39860400002)(199004)(189003)(6506007)(97736004)(6512007)(478600001)(8676002)(1076003)(4744005)(3846002)(14454004)(99286004)(33656002)(386003)(2906002)(86362001)(53936002)(186003)(6116002)(26005)(102836004)(71200400001)(52116002)(76176011)(71190400001)(4326008)(7416002)(217873002)(2616005)(256004)(6486002)(105586002)(6246003)(229853002)(66066001)(476003)(8936002)(316002)(93886005)(25786009)(81156014)(54906003)(81166006)(68736007)(6916009)(36756003)(11346002)(446003)(6436002)(7736002)(486006)(305945005)(106356001);DIR:OUT;SFP:1101;SCL:1;SRVR:DBBPR05MB6473;H:DBBPR05MB6426.eurprd05.prod.outlook.com;FPR:;SPF:None;LANG:en;PTR:InfoNoRecords;A:1;MX:1; received-spf: None (protection.outlook.com: mellanox.com does not designate permitted sender hosts) x-ms-exchange-senderadcheck: 1 x-microsoft-antispam-message-info: +xvNYsBqylgSr92YLOV0YwN6h/OnFAXQQL43w4CQNdG7MIJQXGWg7P645/BSG9/yPhvA40vr9gBxrnI5Eh/okD4U6MFQERpCPtzzfod5qZb2nB2a7GDLSScUEm64//BAA+k8olO64TKUa/Pr0AR4dwYGdLQ2yrBEW5jPYywxts/NiBHV4r8JJRILoAfcsOoHro4nLBkn/0hhuPTOkgutI3uTeehyqarEEqyAGzZBEp2kYHkbVOtA2NLPk68/1JH6lJv2MSdNExZTGeWSH89NtJTKEdGIs5Zuh+J04wiDYBCkJaauRsNHmW7Rf65Y5Um6lirm7nc2cPiUoYMYMwoszHTVItTZUfT66l1CCHQqSHnKgAzyWYYNsPIY+9GDbgdg15YmzvVl1mq5+Iz1btI4LkJKhQP25eCGKfhMbaN4DTE= Content-Type: text/plain; charset="us-ascii" Content-ID: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: Mellanox.com X-MS-Exchange-CrossTenant-Network-Message-Id: bdc53bcc-6a81-4e41-9bca-08d68702e621 X-MS-Exchange-CrossTenant-originalarrivaltime: 30 Jan 2019 22:33:04.0130 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-id: a652971c-7d2e-4d9b-a6a4-d149256f461b X-MS-Exchange-Transport-CrossTenantHeadersStamped: DBBPR05MB6473 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 30, 2019 at 05:30:27PM -0500, Jerome Glisse wrote: > > What is the problem in the HMM mirror that it needs this restriction? >=20 > No restriction at all here. I think i just wasn't understood. Are you are talking about from the exporting side - where the thing creating the VMA can really only put one distinct object into it? Jason