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 58C03C4332F for ; Wed, 27 Oct 2021 06:19:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3E96760FBF for ; Wed, 27 Oct 2021 06:19:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238475AbhJ0GVc (ORCPT ); Wed, 27 Oct 2021 02:21:32 -0400 Received: from mga05.intel.com ([192.55.52.43]:49605 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236251AbhJ0GVZ (ORCPT ); Wed, 27 Oct 2021 02:21:25 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10149"; a="316288806" X-IronPort-AV: E=Sophos;i="5.87,186,1631602800"; d="scan'208";a="316288806" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Oct 2021 23:18:59 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.87,186,1631602800"; d="scan'208";a="447413126" Received: from fmsmsx603.amr.corp.intel.com ([10.18.126.83]) by orsmga003.jf.intel.com with ESMTP; 26 Oct 2021 23:18:58 -0700 Received: from fmsmsx611.amr.corp.intel.com (10.18.126.91) by fmsmsx603.amr.corp.intel.com (10.18.126.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2242.12; Tue, 26 Oct 2021 23:18:58 -0700 Received: from fmsmsx609.amr.corp.intel.com (10.18.126.89) by fmsmsx611.amr.corp.intel.com (10.18.126.91) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2242.12; Tue, 26 Oct 2021 23:18:57 -0700 Received: from fmsedg602.ED.cps.intel.com (10.1.192.136) by fmsmsx609.amr.corp.intel.com (10.18.126.89) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2242.12 via Frontend Transport; Tue, 26 Oct 2021 23:18:57 -0700 Received: from NAM12-BN8-obe.outbound.protection.outlook.com (104.47.55.169) by edgegateway.intel.com (192.55.55.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2242.12; Tue, 26 Oct 2021 23:18:57 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=jzRO1YwF5hA97GPdhAdj52JnlcN+oN76CIfEtLwpfTVU6vUl9UlyFE/DLDmmuAyC4zRCHzGDSy7bfpyxGrRKNK9ykxAYXQvFJUrsWWGLNFEehhARGZr0hP7xPmt+a1gPiey25Slov7EyoYlxflfOXRimaVPn7drsp/bJCquc4q01vVmyClAYRdrYnGv+dI+JyEw/UsI5K2/+95wkJRsDsHerQW7tuU2BDazL8CkLpqY1QG+1HEi/xmwvuCIBMiC/c0WwiBogbxeA3e12IsSg6d1K6+ckRBk9EcAKt11uuy+dUIKDANm/nqe8fmHi9Azpv/TGxG5kYxRnEJuzjMw1rw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=ZvJSwuVqeBmoqCB0y+AdMYZIhgVLpFIZE44E2ihZOBk=; b=kTREqFSfQtD39U1mFmXj690VmdUuivP66UaquccacRscQ1QMihU2EpUglxVhb23bvl17I1Cgw+dXR67TLr7CAnSux/9rlIaG03ZeLcrJVj7DvYuugyYLiJBxHNwhcImjVE25Ke7V0/83Sh8Xblby/VJs+3KTZ4E9gf/0L6uYWbo+lNPUdilAQg9jtkqHW2Ior3LPmOTTqtBCPxs0EJ6Vc/9bfDHrNPgzdHa8zs2e71+6fy5J9pOP+M4o0IuN85zQ+/Nmu4R2r4GsZZrtQZTUAgot9YZE+bL0+CSAhICSSTDMx7iXffFynsuMe8PGKtMVp5EMB20WtoOiiBDVQF1trA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=intel.com; dmarc=pass action=none header.from=intel.com; dkim=pass header.d=intel.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=intel.onmicrosoft.com; s=selector2-intel-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=ZvJSwuVqeBmoqCB0y+AdMYZIhgVLpFIZE44E2ihZOBk=; b=LeqbEHgksy8CCZWkG4V7Yra608kka/7nG1isB/lFi3dqDO6kxP7tspzhKbAMmwkzG7AOPqPpUqtwSffqU1OxR/dxuQA43b9oUSPkvXMmFkDNJKO1WmD925koNOdzoRRG3S45VF+p/XGcd8wLz+9lV+DAqUZuKjvQ2XczT/rTe10= Received: from BN9PR11MB5433.namprd11.prod.outlook.com (2603:10b6:408:11e::13) by BN6PR11MB1617.namprd11.prod.outlook.com (2603:10b6:405:f::14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4628.18; Wed, 27 Oct 2021 06:18:55 +0000 Received: from BN9PR11MB5433.namprd11.prod.outlook.com ([fe80::ecad:62e1:bab9:ac81]) by BN9PR11MB5433.namprd11.prod.outlook.com ([fe80::ecad:62e1:bab9:ac81%7]) with mapi id 15.20.4649.014; Wed, 27 Oct 2021 06:18:55 +0000 From: "Tian, Kevin" To: Paolo Bonzini , Jason Gunthorpe , Alex Williamson CC: "Enrico Weigelt, metux IT consult" , Jean-Philippe Brucker , "Jiang, Dave" , "Raj, Ashok" , "kvm@vger.kernel.org" , Jonathan Corbet , Robin Murphy , LKML , "iommu@lists.linux-foundation.org" , David Gibson , Kirti Wankhede , "David Woodhouse" , Jason Wang Subject: RE: [RFC] /dev/ioasid uAPI proposal Thread-Topic: [RFC] /dev/ioasid uAPI proposal Thread-Index: AddSzQ97/vJYfIW8Gke3qF5WyXyLcQBL2ymAAKTbxpAAKSt7gAAHpf9wAB1YcAAAAm5sgAAA1YgAAADonIAAAEmcgAABzCaAAAHbfwAAAYTsAAAEeLUAAAiRJwAAFF14gAAPozMAAABMSwAAA0bJgAAVeTBAAAlp0QAABjX0AAAAf0IAAABWuQAAAD8IgAAAOC4AAABA0oAAAn0sgAAbQLqAAHzsuQAAHTjUgAALKb+AAAEAJgAACpEpAAAAd4EAAB0JvoAAAK4MgAAFtYKAAAV6DAAAAHyTAAABOkSAG2x1K8A= Date: Wed, 27 Oct 2021 06:18:55 +0000 Message-ID: References: <20210607175926.GJ1002214@nvidia.com> <20210608131547.GE1002214@nvidia.com> <89d30977-119c-49f3-3bf6-d3f7104e07d8@redhat.com> <20210608124700.7b9aa5a6.alex.williamson@redhat.com> <20210608190022.GM1002214@nvidia.com> <671efe89-2430-04fa-5f31-f52589276f01@redhat.com> <20210609115445.GX1002214@nvidia.com> <20210609083134.396055e3.alex.williamson@redhat.com> <20210609144530.GD1002214@nvidia.com> In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: dlp-version: 11.6.200.16 dlp-product: dlpe-windows dlp-reaction: no-action authentication-results: redhat.com; dkim=none (message not signed) header.d=none;redhat.com; dmarc=none action=none header.from=intel.com; x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: 9a75f544-b581-48e6-c772-08d99911a7d3 x-ms-traffictypediagnostic: BN6PR11MB1617: x-ld-processed: 46c98d88-e344-4ed4-8496-4ed7712e255d,ExtAddr x-microsoft-antispam-prvs: x-ms-oob-tlc-oobclassifiers: OLM:9508; x-ms-exchange-senderadcheck: 1 x-ms-exchange-antispam-relay: 0 x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: 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 x-forefront-antispam-report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:BN9PR11MB5433.namprd11.prod.outlook.com;PTR:;CAT:NONE;SFS:(366004)(38070700005)(186003)(7696005)(54906003)(4326008)(110136005)(66946007)(83380400001)(9686003)(38100700002)(66446008)(55016002)(66476007)(66556008)(86362001)(76116006)(2906002)(966005)(71200400001)(64756008)(122000001)(5660300002)(82960400001)(508600001)(53546011)(26005)(33656002)(7416002)(8676002)(6506007)(316002)(8936002)(52536014);DIR:OUT;SFP:1102; x-ms-exchange-antispam-messagedata-chunkcount: 1 x-ms-exchange-antispam-messagedata-0: =?utf-8?B?eTh3dnlBMlU0WkhMWmk1ZVpNb3oxLzFNbXorejJlbXJLWGVTTVVZekp5YVk2?= =?utf-8?B?bzdaeGRHZ2VLTUpsNVFRWHBUaStKZjNtV3lqZ1R6RXBKQnZUckwxd2JWM1ov?= =?utf-8?B?MExaWjQ5VDZ4c1JMUlZ2blVNWHNZUWRGZTB1VU9XeVlLcFBLUjI4OEtMUC9y?= =?utf-8?B?KzlhK0hIbEhxM0dxMTJGamVoSnVpdjVFR1p3YXN1VHVybWpNaUR0QnB3bGFo?= =?utf-8?B?NWFIeEdMQkRySHJaeUUvR0hLQm9nK1Zucy9lNm14WFZNeWY5NDVIN0ZTd2FG?= =?utf-8?B?Q29vQTQ0UmhwaGlmemtRWElvcXJPSUZ1OWQ1dk84QU1uZGtaT3RJV21BRVd2?= =?utf-8?B?cFB0OXN1dEFpak1WOXkrSlUxSnNKMWNTZGZRcDBJU2pZODExUVEydmhmM1B5?= =?utf-8?B?T24xY2hta2xmaGtWM2l3ZFNPTTBVelBndjZZeVhFcFVDT3BCcU5HR1o5M1hY?= =?utf-8?B?cHRQZjZEOXAyblkybVBWMGRUNlpYeUttcWNTWVRkN3ZtR0lTUTBlaWcvY0Vz?= =?utf-8?B?b2J3V1pvdHVpbFBlenFBaXgzSUl2RkFyRk5wbzhGRGNHTko3TUkrT1RGNUsz?= =?utf-8?B?Y1MwRGYrQmY1Zzd5MzVxSEE1bnNNdjJ2NEpIU3R3UXhxQnU5M2x5enNtTmxn?= =?utf-8?B?ekJVb3g1NHhObTJyWE8xdWRaNW9Cenpwa1FTTlM5cEhxeSt2TldPdjZOQmE3?= =?utf-8?B?NGlURkVudUpHZjZ5K3NYcHdQLzVNeGRkUW1vN2JKbXRJNDZwR216QldDdzhT?= =?utf-8?B?NzBYMG5zOWZ2cmhmcGlpQkZENks1aUQ2ZHZTZ0FBTzVlZGltVC9GWXg2TnEw?= =?utf-8?B?UDRUK1hzQ05Td0lNdHVxSTUyNENZRUJnT3NEeDFUbmtZV28yMjhNSzd6d0Y0?= =?utf-8?B?cTZ5bklvV0ZpMmE1RkFTMU50eSs3UUc0S084bWdwaUUwOWg0cWVvMjA2YVdC?= =?utf-8?B?b1RkR1VrTEhzL3JPZUlZYkhQTUxBV2pxYlRxZWdRYk02Y1VncUxNOXNPb1g5?= =?utf-8?B?dXdGQ0NJR3F0akVZam9LMFI0ZGxBRVlXaXp1UkU1Qk1INm5KSGN3cjF1WlY2?= =?utf-8?B?Yk1IcVVnR3paNVF6bEhnWlkwN0JpcEJ5N29xM3hOeTBobDFCVHVJYlZMQlk4?= =?utf-8?B?dzRtQlZleGVpSjZLYVdKangrSUIxaDBtZ0hRWG5aaDJ0UUk5Vmp0dWVnYnpp?= =?utf-8?B?NC93ZDI1Q3JlRVJoSUlCLzd4SlpLTFZWWVp3RUYzRTBJa3ZtR1FWWXNJaitT?= =?utf-8?B?T2RtalZNdW9zKzdaanhnVFgyZHdadk8yQzJkYW1TNUhGUkpLQnZoN2xGNGdQ?= =?utf-8?B?MkNrZlRvZU1iUjQ5aXpSWEJpUkpya3o1TUR6b0VPRWZRMjdqS2FiS3FESTYy?= =?utf-8?B?cmVBZmVGb3NKYy9EQUttU3ZYdXNGenZSUmQyTFh5NFFsSTZjLytDc3kwU3hB?= =?utf-8?B?ZzNMREFqVUVQQkR0VVJwQXZvalFENnNhK01EMmd3cGxlbjFNeTFMZDlqWGUy?= =?utf-8?B?RjRXTEZWdGh0Qk5qWDlQVm84Y0wwTmhWR3BVMityRHpTSXoxcXlGMk1sK1A1?= =?utf-8?B?ZFRlY0hGTjYvQnJiSCtBVWRjSmtCUkxkTkZvOXR2b1oxbGM0dW1KeGJaY3A2?= =?utf-8?B?NGloUU5ZQkgzYmg5aHpUVjlhQkhSVVd0cVpua21RZ1dEem9kWHVyWUIzRUha?= =?utf-8?B?emJvWnp4cXlUSnZENXBRbUg1VzFpa2gxOVRtWTZrZjJ4cHp5N3lVYU9TVmwx?= =?utf-8?B?bldEVFhmY3VZS1JDcTVHK3M2UjJzM2RIclpnMlE1ckZYYUZkZVFNMW5oRmpv?= =?utf-8?B?QzZUV2pFWVFEQVNScW5yTmtNUGl0SnNzb2pxTmFjNDBMTzNIenRCVWpLVDVw?= =?utf-8?B?cWJ2MFhpaXI0bnk4am5hOG5sM2s1Z2tXY2tsRFJtcmFEZ1J4R3FEOEVyeGx6?= =?utf-8?B?dDhzZmNSclhMMWFXWUh0SVRoZGplRVdSc3ZtaVRDeWtpMDZnaS9LaVZ1dGlz?= =?utf-8?B?SVRRZy9rYmUzSS9ycmtFVTlhcWtZYkZLcnhxcDJNcWJGNUNZMzhnNkE3STJE?= =?utf-8?B?TnJpQk44bzhFVWtGR0hDWU5HTFYwdXpydEE3M3R1d2t5cldkS2tHemRPa1pZ?= =?utf-8?B?R2p5aUNrUkhIUFVheXBLUVlzckVwSTN0cU1aMmQ3UXI3MDJnbkZPTzhtYThF?= =?utf-8?Q?hlf4BKptbfmlvbu1WeomeMU=3D?= Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 MIME-Version: 1.0 X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: BN9PR11MB5433.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 9a75f544-b581-48e6-c772-08d99911a7d3 X-MS-Exchange-CrossTenant-originalarrivaltime: 27 Oct 2021 06:18:55.8096 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: 7NtYZ7S33UDesttglSU6wcMTHbLWdi4+TCnBBQde+6R5YEyKhTlaWxPXHjR+nlXL/Xfdgiu4dZuhWjglL0QO+g== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN6PR11MB1617 X-OriginatorOrg: intel.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org SGksIFBhb2xvLA0KDQo+IEZyb206IFBhb2xvIEJvbnppbmkgPHBib256aW5pQHJlZGhhdC5jb20+ DQo+IFNlbnQ6IFdlZG5lc2RheSwgSnVuZSA5LCAyMDIxIDExOjIxIFBNDQo+IA0KPiBPbiAwOS8w Ni8yMSAxNjo0NSwgSmFzb24gR3VudGhvcnBlIHdyb3RlOg0KPiA+IE9uIFdlZCwgSnVuIDA5LCAy MDIxIGF0IDA4OjMxOjM0QU0gLTA2MDAsIEFsZXggV2lsbGlhbXNvbiB3cm90ZToNCj4gPg0KPiA+ PiBJZiB3ZSBnbyBiYWNrIHRvIHRoZSB3YmludmQgaW9jdGwgbWVjaGFuaXNtLCBpZiBJIGNhbGwg dGhhdCBpb2N0bCB3aXRoDQo+ID4+IGFuIGlvYXNpZGZkIHRoYXQgY29udGFpbnMgbm8gZGV2aWNl cywgdGhlbiBJIHNob3VsZG4ndCBiZSBhYmxlIHRvDQo+ID4+IGdlbmVyYXRlIGEgd2JpbnZkIG9u IHRoZSBwcm9jZXNzb3IsIHJpZ2h0PyAgSWYgSSBhZGQgYSBkZXZpY2UsDQo+ID4+IGVzcGVjaWFs bHkgaW4gYSBjb25maWd1cmF0aW9uIHRoYXQgY2FuIGdlbmVyYXRlIG5vbi1jb2hlcmVudCBETUEs IG5vdw0KPiA+PiB0aGF0IGlvY3RsIHNob3VsZCB3b3JrLiAgSWYgSSB0aGVuIHJlbW92ZSBhbGwg ZGV2aWNlcyBmcm9tIHRoYXQgaW9hc2lkLA0KPiA+PiB3aGF0IHRoZW4gaXMgdGhlIGRpZmZlcmVu Y2UgZnJvbSB0aGUgaW5pdGlhbCBzdGF0ZS4gIFNob3VsZCB0aGUgaW9jdGwNCj4gPj4gbm93IHdv cmsgYmVjYXVzZSBpdCB3b3JrZWQgb25jZSBpbiB0aGUgcGFzdD8NCj4gPg0KPiA+IFRoZSBpb2N0 bCBpcyBmaW5lLCBidXQgdGVsbGluZyBLVk0gdG8gZW5hYmxlIFdCSU5WRCBpcyB2ZXJ5IHNpbWls YXIgdG8NCj4gPiBvcGVuIGFuZCB0aGVuIHJlY29uZmlndXJpbmcgdGhlIGlvYXNpZF9mZCBpcyB2 ZXJ5IHNpbWlsYXIgdG8NCj4gPiBjaG1vZC4gRnJvbSBhIHNlY3VyaXR5IHBlcnNwZWN0aXZlIHJl dm9rZSBpcyBub3Qgc3RyaWN0bHkgcmVxdWlyZWQsDQo+ID4gSU1ITy4NCj4gDQo+IEkgYWJzb2x1 dGVseSBkbyAqbm90KiB3YW50IGFuIEFQSSB0aGF0IHRlbGxzIEtWTSB0byBlbmFibGUgV0JJTlZE LiAgVGhpcw0KPiBpcyBub3QgdXAgZm9yIGRpc2N1c3Npb24uDQo+IA0KPiBCdXQgcmVhbGx5LCBs ZXQncyBzdG9wIGNhbGxpbmcgdGhlIGZpbGUgZGVzY3JpcHRvciBhIHNlY3VyaXR5IHByb29mIG9y IGENCj4gY2FwYWJpbGl0eS4gIEl0J3Mgb3ZlcmtpbGw7IGFsbCB0aGF0IHdlIGFyZSBkb2luZyBo ZXJlIGlzIGtlcm5lbA0KPiBhY2NlbGVyYXRpb24gb2YgdGhlIFdCSU5WRCBpb2N0bC4NCj4gDQo+ IEFzIGEgdGhvdWdodCBleHBlcmltZW50LCBsZXQncyBjb25zaWRlciB3aGF0IHdvdWxkIGhhcHBl biBpZiB3YmludmQNCj4gY2F1c2VkIGFuIHVuY29uZGl0aW9uYWwgZXhpdCBmcm9tIGd1ZXN0IHRv IHVzZXJzcGFjZS4gIFVzZXJzcGFjZSB3b3VsZA0KPiByZWFjdCBieSBpbnZva2luZyB0aGUgaW9j dGwgb24gdGhlIGlvYXNpZC4gIFRoZSBwcm9wb3NlZCBmdW5jdGlvbmFsaXR5DQo+IGlzIGp1c3Qg YW4gYWNjZWxlcmF0aW9uIG9mIHRoaXMgc2FtZSB0aGluZywgYXZvaWRpbmcgdGhlDQo+IGd1ZXN0 LT5LVk0tPnVzZXJzcGFjZS0+SU9BU0lELT53YmludmQgdHJpcC4NCg0KV2hpbGUgdGhlIGNvbmNl cHQgaGVyZSBtYWtlcyBzZW5zZSwgaW4gcmVhbGl0eSBpbXBsZW1lbnRpbmcgYSB3YmludmQNCmlv Y3RsIGZvciB1c2Vyc3BhY2UgcmVxdWlyaW5nIGlvbW11ZmQgKHByZXZpb3VzIC9kZXYvaW9hc2lk IGlzIHJlbmFtZWQNCnRvIC9kZXYvaW9tbXUgbm93KSB0byB0cmFjayBkaXJ0eSBDUFVzIHRoYXQg YSBnaXZlbiBwcm9jZXNzIGhhcyBiZWVuIA0KcnVubmluZyBzaW5jZSB3YmludmQgb25seSBmbHVz aGVzIGxvY2FsIGNhY2hlLiBLVk0gdHJhY2tzIGRpcnR5IENQVXMgYnkgDQpyZWdpc3RlcmluZyBw cmVlbXB0IG5vdGlmaWVyIG9uIHRoZSBjdXJyZW50IHZDUFUuIGlvbW11ZmQgbWF5IGRvIHRoZSAN CnNhbWUgdGhpbmcgZm9yIHRoZSB0aHJlYWQgd2hpY2ggb3BlbnMgL2Rldi9pb21tdSwgYnV0IHBl ciBiZWxvdw0KZGlzY3Vzc2lvbiBvbmUgb3BlbiBpcyB3aGV0aGVyIGl0J3Mgd29ydGh3aGlsZSBh ZGRpbmcgc3VjaCBoYXNzbGUgZm9yDQpzb21ldGhpbmcgd2hpY2ggbm8gcmVhbCB1c2VyIGlzIGlu dGVyZXN0ZWQgaW4gdG9kYXkgZXhjZXB0IGt2bToNCg0KaHR0cHM6Ly9sb3JlLmtlcm5lbC5vcmcv bGttbC8yMDIxMTAyNTIzMzQ1OS5HTTI3NDQ1NDRAbnZpZGlhLmNvbS8NCg0KSXMgaXQgb2sgdG8g b21pdCB0aGUgYWN0dWFsIHdiaW52ZCBpb2N0bCBoZXJlIGFuZCBqdXN0IGxldmVyYWdlIHZmaW8t a3ZtDQpjb250cmFjdCB0byBtYW5hZ2Ugd2hldGhlciBndWVzdCB3YmludmQgaXMgZW11bGF0ZWQg YXMgbm8tb3A/IEl0IGlzIA0Kc3RpbGwgaW9tbXVmZCB3aGljaCBkZWNpZGVzIHdoZXRoZXIgd2Jp bnZkIGlzIGFsbG93ZWQgKGJhc2VkIG9uIElPQVMgDQphbmQgZGV2aWNlIGF0dGFjaCBpbmZvcm1h dGlvbikgYnV0IGp1c3Qgc29ydCBvZiBzcGVjaWFsIGNhc2luZyB0aGF0IHRoZSANCm9wZXJhdGlv biBjYW4gb25seSBiZSBkb25lIHZpYSBrdm0gcGF0aC4uLg0KDQpidHcgZG9lcyBrdm0gY29tbXVu aXR5IHNldCBhIHN0cmljdCBjcml0ZXJpYSB0aGF0IGFueSBvcGVyYXRpb24gdGhhdA0KdGhlIGd1 ZXN0IGNhbiBkbyBtdXN0IGJlIGZpcnN0IGNhcnJpZWQgaW4gaG9zdCB1QVBJIGZpcnN0PyBJbiBj b25jZXB0DQpLVk0gZGVhbHMgd2l0aCBJU0EtbGV2ZWwgdG8gY292ZXIgYm90aCBndWVzdCBrZXJu ZWwgYW5kIGd1ZXN0IHVzZXINCndoaWxlIGhvc3QgdUFQSSBpcyBvbmx5IGZvciBob3N0IHVzZXIu IEludHJvZHVjaW5nIG5ldyB1QVBJcyB0byBhbGxvdw0KaG9zdCB1c2VyIGRvaW5nIHdoYXRldmVy IGd1ZXN0IGtlcm5lbCBjYW4gZG8gc291bmRzIGlkZWFsLCBidXQgbm90DQpleGFjdGx5IG5lY2Vz c2FyeSBpbWhvLg0KDQo+IA0KPiBUaGlzIGlzIHdoeSB0aGUgQVBJIHRoYXQgSSB3YW50LCBhbmQg dGhhdCBpcyBhbHJlYWR5IGV4aXN0cyBmb3IgVkZJTw0KPiBncm91cCBmaWxlIGRlc2NyaXB0b3Jz LCBpbmZvcm1zIEtWTSBvZiB3aGljaCAiaW9jdGxzIiB0aGUgZ3Vlc3Qgc2hvdWxkDQo+IGJlIGFi bGUgdG8gZG8gdmlhIHByaXZpbGVnZWQgaW5zdHJ1Y3Rpb25zWzFdLiAgVGhlbiB0aGUga2VybmVs IHdvcmtzIG91dA0KPiB3aXRoIEtWTSBob3cgdG8gZW5zdXJlIGEgMToxIGNvcnJlc3BvbmRlbmNl IGJldHdlZW4gdGhlIG9wZXJhdGlvbiBvZiB0aGUNCj4gaW9jdGxzIGFuZCB0aGUgcHJpdmlsZWdl ZCBvcGVyYXRpb25zLg0KPiANCj4gT25lIHdheSB0byBkbyBpdCB3b3VsZCBiZSB0byBhbHdheXMg dHJhcCBXQklOVkQgYW5kIGludm9rZSB0aGUgc2FtZQ0KPiBrZXJuZWwgZnVuY3Rpb24gdGhhdCBp bXBsZW1lbnRzIHRoZSBpb2N0bC4gIFRoZSBmdW5jdGlvbiB3b3VsZCBkbyBlaXRoZXINCj4gYSB3 YmludmQgb3Igbm90aGluZywgYmFzZWQgb24gd2hldGhlciB0aGUgaW9hc2lkIGhhcyBhbnkgZGV2 aWNlLiAgVGhlDQo+IG5leHQgbG9naWNhbCBzdGVwIGlzIGEgbm90aWZpY2F0aW9uIG1lY2hhbmlz bSB0aGF0IGVuYWJsZXMgV0JJTlZEIChieQ0KPiBkaXNhYmxpbmcgdGhlIFdCSU5WRCBpbnRlcmNl cHQpIHdoZW4gdGhlcmUgYXJlIGRldmljZXMgaW4gdGhlIGlvYXNpZGZkLA0KPiBhbmQgZGlzYWJs ZXMgV0JJTlZEIChieSBlbmFibGluZyBhIG5vLW9wIGludGVyY2VwdCkgd2hlbiB0aGVyZSBhcmUg bm9uZS4NCj4gDQo+IEFuZCBpbiBmYWN0IG9uY2UgYWxsIFZGSU8gZGV2aWNlcyBhcmUgZ29uZSwg d2JpbnZkIGlzIGZvciBhbGwgcHVycG9zZXMgYQ0KPiBuby1vcCBhcyBmYXIgYXMgdGhlIGd1ZXN0 IGtlcm5lbCBjYW4gdGVsbC4gIFNvIHRoZXJlJ3Mgbm8gcmVhc29uIHRvDQo+IHRyZWF0IGl0IGFz IGFueXRoaW5nIGJ1dCBhIG5vLW9wLg0KPiANCj4gVGhhbmtzLA0KPiANCj4gUGFvbG8NCj4gDQo+ IFsxXSBBcyBhbiBhc2lkZSwgSSBtdXN0IGFkbWl0IEkgZGlkbid0IGVudGlyZWx5IHVuZGVyc3Rh bmQgdGhlIGRlc2lnbiBvZg0KPiB0aGUgS1ZNLVZGSU8gZGV2aWNlIGJhY2sgd2hlbiBBbGV4IGFk ZGVkIGl0LiAgQnV0IHdpdGggdGhpcyBtb2RlbCBpdCB3YXMNCj4gYWJzb2x1dGVseSB0aGUgcmln aHQgdGhpbmcgdG8gZG8sIGFuZCBpdCByZW1haW5zIHRoZSByaWdodCB0aGluZyB0byBkbw0KPiBl dmVuIGlmIFZGSU8gZ3JvdXBzIGFyZSByZXBsYWNlZCB3aXRoIElPQVNJRCBmaWxlIGRlc2NyaXB0 b3JzLg0KDQo= 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 A58B1C433F5 for ; Wed, 27 Oct 2021 06:19:07 +0000 (UTC) Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3B3C560FBF for ; Wed, 27 Oct 2021 06:19:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 3B3C560FBF Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id 0609E40262; Wed, 27 Oct 2021 06:19:07 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id DCUBfSQV-PrZ; Wed, 27 Oct 2021 06:19:06 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [IPv6:2605:bc80:3010:104::8cd3:938]) by smtp4.osuosl.org (Postfix) with ESMTPS id BFE38401FE; Wed, 27 Oct 2021 06:19:05 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 9A32CC0019; Wed, 27 Oct 2021 06:19:05 +0000 (UTC) Received: from smtp2.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by lists.linuxfoundation.org (Postfix) with ESMTP id B77CFC000E for ; Wed, 27 Oct 2021 06:19:03 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id 989A04013F for ; Wed, 27 Oct 2021 06:19:03 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Authentication-Results: smtp2.osuosl.org (amavisd-new); dkim=pass (1024-bit key) header.d=intel.onmicrosoft.com Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id JpElYvXxEA0L for ; Wed, 27 Oct 2021 06:19:02 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by smtp2.osuosl.org (Postfix) with ESMTPS id 1524F40109 for ; Wed, 27 Oct 2021 06:19:01 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10149"; a="229942303" X-IronPort-AV: E=Sophos;i="5.87,186,1631602800"; d="scan'208";a="229942303" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Oct 2021 23:18:59 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.87,186,1631602800"; d="scan'208";a="447413126" Received: from fmsmsx603.amr.corp.intel.com ([10.18.126.83]) by orsmga003.jf.intel.com with ESMTP; 26 Oct 2021 23:18:58 -0700 Received: from fmsmsx611.amr.corp.intel.com (10.18.126.91) by fmsmsx603.amr.corp.intel.com (10.18.126.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2242.12; Tue, 26 Oct 2021 23:18:58 -0700 Received: from fmsmsx609.amr.corp.intel.com (10.18.126.89) by fmsmsx611.amr.corp.intel.com (10.18.126.91) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2242.12; Tue, 26 Oct 2021 23:18:57 -0700 Received: from fmsedg602.ED.cps.intel.com (10.1.192.136) by fmsmsx609.amr.corp.intel.com (10.18.126.89) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2242.12 via Frontend Transport; Tue, 26 Oct 2021 23:18:57 -0700 Received: from NAM12-BN8-obe.outbound.protection.outlook.com (104.47.55.169) by edgegateway.intel.com (192.55.55.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2242.12; Tue, 26 Oct 2021 23:18:57 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=jzRO1YwF5hA97GPdhAdj52JnlcN+oN76CIfEtLwpfTVU6vUl9UlyFE/DLDmmuAyC4zRCHzGDSy7bfpyxGrRKNK9ykxAYXQvFJUrsWWGLNFEehhARGZr0hP7xPmt+a1gPiey25Slov7EyoYlxflfOXRimaVPn7drsp/bJCquc4q01vVmyClAYRdrYnGv+dI+JyEw/UsI5K2/+95wkJRsDsHerQW7tuU2BDazL8CkLpqY1QG+1HEi/xmwvuCIBMiC/c0WwiBogbxeA3e12IsSg6d1K6+ckRBk9EcAKt11uuy+dUIKDANm/nqe8fmHi9Azpv/TGxG5kYxRnEJuzjMw1rw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=ZvJSwuVqeBmoqCB0y+AdMYZIhgVLpFIZE44E2ihZOBk=; b=kTREqFSfQtD39U1mFmXj690VmdUuivP66UaquccacRscQ1QMihU2EpUglxVhb23bvl17I1Cgw+dXR67TLr7CAnSux/9rlIaG03ZeLcrJVj7DvYuugyYLiJBxHNwhcImjVE25Ke7V0/83Sh8Xblby/VJs+3KTZ4E9gf/0L6uYWbo+lNPUdilAQg9jtkqHW2Ior3LPmOTTqtBCPxs0EJ6Vc/9bfDHrNPgzdHa8zs2e71+6fy5J9pOP+M4o0IuN85zQ+/Nmu4R2r4GsZZrtQZTUAgot9YZE+bL0+CSAhICSSTDMx7iXffFynsuMe8PGKtMVp5EMB20WtoOiiBDVQF1trA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=intel.com; dmarc=pass action=none header.from=intel.com; dkim=pass header.d=intel.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=intel.onmicrosoft.com; s=selector2-intel-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=ZvJSwuVqeBmoqCB0y+AdMYZIhgVLpFIZE44E2ihZOBk=; b=LeqbEHgksy8CCZWkG4V7Yra608kka/7nG1isB/lFi3dqDO6kxP7tspzhKbAMmwkzG7AOPqPpUqtwSffqU1OxR/dxuQA43b9oUSPkvXMmFkDNJKO1WmD925koNOdzoRRG3S45VF+p/XGcd8wLz+9lV+DAqUZuKjvQ2XczT/rTe10= Received: from BN9PR11MB5433.namprd11.prod.outlook.com (2603:10b6:408:11e::13) by BN6PR11MB1617.namprd11.prod.outlook.com (2603:10b6:405:f::14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4628.18; Wed, 27 Oct 2021 06:18:55 +0000 Received: from BN9PR11MB5433.namprd11.prod.outlook.com ([fe80::ecad:62e1:bab9:ac81]) by BN9PR11MB5433.namprd11.prod.outlook.com ([fe80::ecad:62e1:bab9:ac81%7]) with mapi id 15.20.4649.014; Wed, 27 Oct 2021 06:18:55 +0000 From: "Tian, Kevin" To: Paolo Bonzini , Jason Gunthorpe , Alex Williamson Subject: RE: [RFC] /dev/ioasid uAPI proposal Thread-Topic: [RFC] /dev/ioasid uAPI proposal Thread-Index: AddSzQ97/vJYfIW8Gke3qF5WyXyLcQBL2ymAAKTbxpAAKSt7gAAHpf9wAB1YcAAAAm5sgAAA1YgAAADonIAAAEmcgAABzCaAAAHbfwAAAYTsAAAEeLUAAAiRJwAAFF14gAAPozMAAABMSwAAA0bJgAAVeTBAAAlp0QAABjX0AAAAf0IAAABWuQAAAD8IgAAAOC4AAABA0oAAAn0sgAAbQLqAAHzsuQAAHTjUgAALKb+AAAEAJgAACpEpAAAAd4EAAB0JvoAAAK4MgAAFtYKAAAV6DAAAAHyTAAABOkSAG2x1K8A= Date: Wed, 27 Oct 2021 06:18:55 +0000 Message-ID: References: <20210607175926.GJ1002214@nvidia.com> <20210608131547.GE1002214@nvidia.com> <89d30977-119c-49f3-3bf6-d3f7104e07d8@redhat.com> <20210608124700.7b9aa5a6.alex.williamson@redhat.com> <20210608190022.GM1002214@nvidia.com> <671efe89-2430-04fa-5f31-f52589276f01@redhat.com> <20210609115445.GX1002214@nvidia.com> <20210609083134.396055e3.alex.williamson@redhat.com> <20210609144530.GD1002214@nvidia.com> In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: dlp-version: 11.6.200.16 dlp-product: dlpe-windows dlp-reaction: no-action authentication-results: redhat.com; dkim=none (message not signed) header.d=none;redhat.com; dmarc=none action=none header.from=intel.com; x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: 9a75f544-b581-48e6-c772-08d99911a7d3 x-ms-traffictypediagnostic: BN6PR11MB1617: x-ld-processed: 46c98d88-e344-4ed4-8496-4ed7712e255d,ExtAddr x-microsoft-antispam-prvs: x-ms-oob-tlc-oobclassifiers: OLM:9508; x-ms-exchange-senderadcheck: 1 x-ms-exchange-antispam-relay: 0 x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: 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 x-forefront-antispam-report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:BN9PR11MB5433.namprd11.prod.outlook.com; PTR:; CAT:NONE; SFS:(366004)(38070700005)(186003)(7696005)(54906003)(4326008)(110136005)(66946007)(83380400001)(9686003)(38100700002)(66446008)(55016002)(66476007)(66556008)(86362001)(76116006)(2906002)(966005)(71200400001)(64756008)(122000001)(5660300002)(82960400001)(508600001)(53546011)(26005)(33656002)(7416002)(8676002)(6506007)(316002)(8936002)(52536014); DIR:OUT; SFP:1102; x-ms-exchange-antispam-messagedata-chunkcount: 1 x-ms-exchange-antispam-messagedata-0: =?utf-8?B?eTh3dnlBMlU0WkhMWmk1ZVpNb3oxLzFNbXorejJlbXJLWGVTTVVZekp5YVk2?= =?utf-8?B?bzdaeGRHZ2VLTUpsNVFRWHBUaStKZjNtV3lqZ1R6RXBKQnZUckwxd2JWM1ov?= =?utf-8?B?MExaWjQ5VDZ4c1JMUlZ2blVNWHNZUWRGZTB1VU9XeVlLcFBLUjI4OEtMUC9y?= =?utf-8?B?KzlhK0hIbEhxM0dxMTJGamVoSnVpdjVFR1p3YXN1VHVybWpNaUR0QnB3bGFo?= =?utf-8?B?NWFIeEdMQkRySHJaeUUvR0hLQm9nK1Zucy9lNm14WFZNeWY5NDVIN0ZTd2FG?= =?utf-8?B?Q29vQTQ0UmhwaGlmemtRWElvcXJPSUZ1OWQ1dk84QU1uZGtaT3RJV21BRVd2?= =?utf-8?B?cFB0OXN1dEFpak1WOXkrSlUxSnNKMWNTZGZRcDBJU2pZODExUVEydmhmM1B5?= =?utf-8?B?T24xY2hta2xmaGtWM2l3ZFNPTTBVelBndjZZeVhFcFVDT3BCcU5HR1o5M1hY?= =?utf-8?B?cHRQZjZEOXAyblkybVBWMGRUNlpYeUttcWNTWVRkN3ZtR0lTUTBlaWcvY0Vz?= =?utf-8?B?b2J3V1pvdHVpbFBlenFBaXgzSUl2RkFyRk5wbzhGRGNHTko3TUkrT1RGNUsz?= =?utf-8?B?Y1MwRGYrQmY1Zzd5MzVxSEE1bnNNdjJ2NEpIU3R3UXhxQnU5M2x5enNtTmxn?= =?utf-8?B?ekJVb3g1NHhObTJyWE8xdWRaNW9Cenpwa1FTTlM5cEhxeSt2TldPdjZOQmE3?= =?utf-8?B?NGlURkVudUpHZjZ5K3NYcHdQLzVNeGRkUW1vN2JKbXRJNDZwR216QldDdzhT?= =?utf-8?B?NzBYMG5zOWZ2cmhmcGlpQkZENks1aUQ2ZHZTZ0FBTzVlZGltVC9GWXg2TnEw?= =?utf-8?B?UDRUK1hzQ05Td0lNdHVxSTUyNENZRUJnT3NEeDFUbmtZV28yMjhNSzd6d0Y0?= =?utf-8?B?cTZ5bklvV0ZpMmE1RkFTMU50eSs3UUc0S084bWdwaUUwOWg0cWVvMjA2YVdC?= =?utf-8?B?b1RkR1VrTEhzL3JPZUlZYkhQTUxBV2pxYlRxZWdRYk02Y1VncUxNOXNPb1g5?= =?utf-8?B?dXdGQ0NJR3F0akVZam9LMFI0ZGxBRVlXaXp1UkU1Qk1INm5KSGN3cjF1WlY2?= =?utf-8?B?Yk1IcVVnR3paNVF6bEhnWlkwN0JpcEJ5N29xM3hOeTBobDFCVHVJYlZMQlk4?= =?utf-8?B?dzRtQlZleGVpSjZLYVdKangrSUIxaDBtZ0hRWG5aaDJ0UUk5Vmp0dWVnYnpp?= =?utf-8?B?NC93ZDI1Q3JlRVJoSUlCLzd4SlpLTFZWWVp3RUYzRTBJa3ZtR1FWWXNJaitT?= =?utf-8?B?T2RtalZNdW9zKzdaanhnVFgyZHdadk8yQzJkYW1TNUhGUkpLQnZoN2xGNGdQ?= =?utf-8?B?MkNrZlRvZU1iUjQ5aXpSWEJpUkpya3o1TUR6b0VPRWZRMjdqS2FiS3FESTYy?= =?utf-8?B?cmVBZmVGb3NKYy9EQUttU3ZYdXNGenZSUmQyTFh5NFFsSTZjLytDc3kwU3hB?= =?utf-8?B?ZzNMREFqVUVQQkR0VVJwQXZvalFENnNhK01EMmd3cGxlbjFNeTFMZDlqWGUy?= =?utf-8?B?RjRXTEZWdGh0Qk5qWDlQVm84Y0wwTmhWR3BVMityRHpTSXoxcXlGMk1sK1A1?= =?utf-8?B?ZFRlY0hGTjYvQnJiSCtBVWRjSmtCUkxkTkZvOXR2b1oxbGM0dW1KeGJaY3A2?= =?utf-8?B?NGloUU5ZQkgzYmg5aHpUVjlhQkhSVVd0cVpua21RZ1dEem9kWHVyWUIzRUha?= =?utf-8?B?emJvWnp4cXlUSnZENXBRbUg1VzFpa2gxOVRtWTZrZjJ4cHp5N3lVYU9TVmwx?= =?utf-8?B?bldEVFhmY3VZS1JDcTVHK3M2UjJzM2RIclpnMlE1ckZYYUZkZVFNMW5oRmpv?= =?utf-8?B?QzZUV2pFWVFEQVNScW5yTmtNUGl0SnNzb2pxTmFjNDBMTzNIenRCVWpLVDVw?= =?utf-8?B?cWJ2MFhpaXI0bnk4am5hOG5sM2s1Z2tXY2tsRFJtcmFEZ1J4R3FEOEVyeGx6?= =?utf-8?B?dDhzZmNSclhMMWFXWUh0SVRoZGplRVdSc3ZtaVRDeWtpMDZnaS9LaVZ1dGlz?= =?utf-8?B?SVRRZy9rYmUzSS9ycmtFVTlhcWtZYkZLcnhxcDJNcWJGNUNZMzhnNkE3STJE?= =?utf-8?B?TnJpQk44bzhFVWtGR0hDWU5HTFYwdXpydEE3M3R1d2t5cldkS2tHemRPa1pZ?= =?utf-8?B?R2p5aUNrUkhIUFVheXBLUVlzckVwSTN0cU1aMmQ3UXI3MDJnbkZPTzhtYThF?= =?utf-8?Q?hlf4BKptbfmlvbu1WeomeMU=3D?= MIME-Version: 1.0 X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: BN9PR11MB5433.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 9a75f544-b581-48e6-c772-08d99911a7d3 X-MS-Exchange-CrossTenant-originalarrivaltime: 27 Oct 2021 06:18:55.8096 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: 7NtYZ7S33UDesttglSU6wcMTHbLWdi4+TCnBBQde+6R5YEyKhTlaWxPXHjR+nlXL/Xfdgiu4dZuhWjglL0QO+g== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN6PR11MB1617 X-OriginatorOrg: intel.com Cc: Jean-Philippe Brucker , "Jiang, Dave" , "Raj, Ashok" , "kvm@vger.kernel.org" , Jonathan Corbet , David Woodhouse , Jason Wang , LKML , Kirti Wankhede , "iommu@lists.linux-foundation.org" , "Enrico Weigelt, metux IT consult" , Robin Murphy , David Gibson X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" Hi, Paolo, > From: Paolo Bonzini > Sent: Wednesday, June 9, 2021 11:21 PM > > On 09/06/21 16:45, Jason Gunthorpe wrote: > > On Wed, Jun 09, 2021 at 08:31:34AM -0600, Alex Williamson wrote: > > > >> If we go back to the wbinvd ioctl mechanism, if I call that ioctl with > >> an ioasidfd that contains no devices, then I shouldn't be able to > >> generate a wbinvd on the processor, right? If I add a device, > >> especially in a configuration that can generate non-coherent DMA, now > >> that ioctl should work. If I then remove all devices from that ioasid, > >> what then is the difference from the initial state. Should the ioctl > >> now work because it worked once in the past? > > > > The ioctl is fine, but telling KVM to enable WBINVD is very similar to > > open and then reconfiguring the ioasid_fd is very similar to > > chmod. From a security perspective revoke is not strictly required, > > IMHO. > > I absolutely do *not* want an API that tells KVM to enable WBINVD. This > is not up for discussion. > > But really, let's stop calling the file descriptor a security proof or a > capability. It's overkill; all that we are doing here is kernel > acceleration of the WBINVD ioctl. > > As a thought experiment, let's consider what would happen if wbinvd > caused an unconditional exit from guest to userspace. Userspace would > react by invoking the ioctl on the ioasid. The proposed functionality > is just an acceleration of this same thing, avoiding the > guest->KVM->userspace->IOASID->wbinvd trip. While the concept here makes sense, in reality implementing a wbinvd ioctl for userspace requiring iommufd (previous /dev/ioasid is renamed to /dev/iommu now) to track dirty CPUs that a given process has been running since wbinvd only flushes local cache. KVM tracks dirty CPUs by registering preempt notifier on the current vCPU. iommufd may do the same thing for the thread which opens /dev/iommu, but per below discussion one open is whether it's worthwhile adding such hassle for something which no real user is interested in today except kvm: https://lore.kernel.org/lkml/20211025233459.GM2744544@nvidia.com/ Is it ok to omit the actual wbinvd ioctl here and just leverage vfio-kvm contract to manage whether guest wbinvd is emulated as no-op? It is still iommufd which decides whether wbinvd is allowed (based on IOAS and device attach information) but just sort of special casing that the operation can only be done via kvm path... btw does kvm community set a strict criteria that any operation that the guest can do must be first carried in host uAPI first? In concept KVM deals with ISA-level to cover both guest kernel and guest user while host uAPI is only for host user. Introducing new uAPIs to allow host user doing whatever guest kernel can do sounds ideal, but not exactly necessary imho. > > This is why the API that I want, and that is already exists for VFIO > group file descriptors, informs KVM of which "ioctls" the guest should > be able to do via privileged instructions[1]. Then the kernel works out > with KVM how to ensure a 1:1 correspondence between the operation of the > ioctls and the privileged operations. > > One way to do it would be to always trap WBINVD and invoke the same > kernel function that implements the ioctl. The function would do either > a wbinvd or nothing, based on whether the ioasid has any device. The > next logical step is a notification mechanism that enables WBINVD (by > disabling the WBINVD intercept) when there are devices in the ioasidfd, > and disables WBINVD (by enabling a no-op intercept) when there are none. > > And in fact once all VFIO devices are gone, wbinvd is for all purposes a > no-op as far as the guest kernel can tell. So there's no reason to > treat it as anything but a no-op. > > Thanks, > > Paolo > > [1] As an aside, I must admit I didn't entirely understand the design of > the KVM-VFIO device back when Alex added it. But with this model it was > absolutely the right thing to do, and it remains the right thing to do > even if VFIO groups are replaced with IOASID file descriptors. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu