Received: by 2002:a05:6a10:a0d1:0:0:0:0 with SMTP id j17csp148663pxa; Tue, 11 Aug 2020 20:36:48 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxyGl3hIwpmCeLowl7qbmrr4PkTPuIIFAVdg2IkuoKRymr+hXV26DfSORtY2gIEXXKCnk1I X-Received: by 2002:a17:906:2a04:: with SMTP id j4mr11028635eje.440.1597203407980; Tue, 11 Aug 2020 20:36:47 -0700 (PDT) ARC-Seal: i=2; a=rsa-sha256; t=1597203407; cv=pass; d=google.com; s=arc-20160816; b=u/irp+6n5HcOaTlo6LCnBF5KmjSF9gnHwLtZKeWrn/LQGpDxJwhmWxvWGLqztAu3on O1rKCUki2g1ToL9fSP4oH7pfiam7EBsoUxInU4KQeC0ErCpep6z+6Kt2OBTqRXSwwonA dIY7Amp8sobl2Mh8GrDAFfUrAwMIk/WsI7UTfdDde/FeM8M8+UIxXL79Ram6Uhi8YdrS T9JksK3iaWUU8zXpS9e+xK89BpwlJgVBCLj1YMb68KSQ/GY85gOpsIP6pLxetDvEZnOM ZL28JbxuePTimCv06xf1HZUgw6wTNbVBBh+rD0pKzuUUcYQtnHuMZD7NqpnZ8LHjW2w9 6TtQ== ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:mime-version:content-transfer-encoding :dlp-reaction:dlp-product:dlp-version:content-language :accept-language:in-reply-to:references:message-id:date:thread-index :thread-topic:subject:cc:to:from:dkim-signature:ironport-sdr :ironport-sdr; bh=b5o64O+z66IJsTsAJJosdgRdvPhnWXG7eApOu7cZ4nI=; b=U/NTbCyUXPpEHfl1WtsrvxJUoHtu4vqIV9lQqqJCaJcecE0saDcuFVEE+IeBrY2yGT eo3QChDqX3rOYEgceQQyRxuuDhjmhJVgQ4HAn3D/vE3GXmRckMoyF2gfhXsMDS/5lbnt fzQB75UTWQbrv+yNqCM4Zj6rfYGeWtefVh/0NrMh3iHjTFYzSfYsTyudfhyp+4aY0cXR DsOD7UPttYIfRrdUcD7Rafsn7exlqrcxA/yTDZZNCoEftKaaa1L4ptl2ZWWBj/crSZkU OGnxznluMQIFfJjLc6qyKnbrv/2RM92oHEDMRJ+wy8Utd8iTqoLH3sezHIH9OZhniZxf jnDg== ARC-Authentication-Results: i=2; mx.google.com; dkim=pass header.i=@intel.onmicrosoft.com header.s=selector2-intel-onmicrosoft-com header.b=P7E6p5tr; arc=pass (i=1 spf=pass spfdomain=intel.com dkim=pass dkdomain=intel.com dmarc=pass fromdomain=intel.com); spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=intel.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id p16si370902ejb.342.2020.08.11.20.36.17; Tue, 11 Aug 2020 20:36:47 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@intel.onmicrosoft.com header.s=selector2-intel-onmicrosoft-com header.b=P7E6p5tr; arc=pass (i=1 spf=pass spfdomain=intel.com dkim=pass dkdomain=intel.com dmarc=pass fromdomain=intel.com); spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=intel.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726512AbgHLDfs (ORCPT + 99 others); Tue, 11 Aug 2020 23:35:48 -0400 Received: from mga18.intel.com ([134.134.136.126]:37703 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726333AbgHLDfs (ORCPT ); Tue, 11 Aug 2020 23:35:48 -0400 IronPort-SDR: vzWgV3GZDYxTaGPSx6usdHR7H14WxjrUzy5z/Aqg5bDFbyeGbBiy0RqRJplDrKbIahIx+Ir/20 gnG/Al82Ap/w== X-IronPort-AV: E=McAfee;i="6000,8403,9710"; a="141492776" X-IronPort-AV: E=Sophos;i="5.76,302,1592895600"; d="scan'208";a="141492776" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Aug 2020 20:35:46 -0700 IronPort-SDR: zRnKIecbbxvlOBMwn4bP59lZVKSt6L1HvwLorTd/DWC3bpTiAPSYPk8ITlMg3DJTgbn50aFNK0 X4mR40yLTQZg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.76,302,1592895600"; d="scan'208";a="290901974" Received: from orsmsx606-2.jf.intel.com (HELO ORSMSX606.amr.corp.intel.com) ([10.22.229.86]) by orsmga003.jf.intel.com with ESMTP; 11 Aug 2020 20:35:46 -0700 Received: from orsmsx612.amr.corp.intel.com (10.22.229.25) by ORSMSX606.amr.corp.intel.com (10.22.229.19) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1713.5; Tue, 11 Aug 2020 20:35:46 -0700 Received: from ORSEDG002.ED.cps.intel.com (10.7.248.5) by orsmsx612.amr.corp.intel.com (10.22.229.25) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.1713.5 via Frontend Transport; Tue, 11 Aug 2020 20:35:46 -0700 Received: from NAM10-BN7-obe.outbound.protection.outlook.com (104.47.70.103) by edgegateway.intel.com (134.134.137.101) with Microsoft SMTP Server (TLS) id 14.3.439.0; Tue, 11 Aug 2020 20:35:44 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=mLpr4vLz9vObUzqkDykC9EDQ4B5OeSDn2xdIMiKmDZ4tSgjtBJuSGx4KhlUVBi9zBB6sIXjWhSFJjMaxTtRkXwMTbknQM06Ze9B+1ytjd1055Y8DNC+Bd6XlVeu03rjq4Ze90F9lbhi3w4w5HTQUEBuNKa0s7rwcv2KjX5jKNa9t9rYpPq0Spaq/a4ItG436GavgwAcU3WkSLQgJRqS9CJUYFe8hoQdRCXFwW1KWJtdJHO1LVmYlR71X8/NQEPXSspZclf951DFocWNIkR0XPRSrdNrsLXTR9L7RH84XvGi+k221yknZbjKsLTBQjoOT5lTZ+mJM7fcnQJOm7IdMRg== 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-SenderADCheck; bh=b5o64O+z66IJsTsAJJosdgRdvPhnWXG7eApOu7cZ4nI=; b=W10ykzHA9tn+JMX1J9KsMGl465HQfFFg9+gwaim21ahZyGowDb90CHvu+Se6WBzQTFT2gwkiZXOKnIwDnBuJQPWOyL61ov5v22bKPyDVKQKaTJV1paRFkTk7C0M8qOXWzs1inl9z5mhB424c/qcavRPrTbnoqioOGb0hzA1dHiJK5Ad/pXSeacz7/N3b/wEUlChdkXuxO6oxcxCsufLTA6/AHt2dn4M3mTIb0RNf8dpxId/mNGmVOIMeEB7cbC7aQ6UYXl1gxIJBiBy7BdnfOtnkdvYe9ArLO2T21Wh76dzLCi18C7XtuE92rVs4zmnAhVxJElfc5gjt14kArT06lw== 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=b5o64O+z66IJsTsAJJosdgRdvPhnWXG7eApOu7cZ4nI=; b=P7E6p5trOcAdHXF/gke///FMtAaILXpvNa7xVk5rxuwbuoKQHaytKxhzO/Sqs2XKWMmRssfkmrKabft3EoT2x5Qc0XwXcOttIdrvN0Rwxy8K3dV0uRJsUrf+QYsXvWzwYcQAVb8JL3s6k8hqyqBAutJXCegWdEKU6wmJO7fpQCA= Received: from MWHPR11MB1645.namprd11.prod.outlook.com (2603:10b6:301:b::12) by MWHPR11MB1647.namprd11.prod.outlook.com (2603:10b6:301:d::12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3261.17; Wed, 12 Aug 2020 03:35:39 +0000 Received: from MWHPR11MB1645.namprd11.prod.outlook.com ([fe80::6dfe:feb8:25f1:ac9c]) by MWHPR11MB1645.namprd11.prod.outlook.com ([fe80::6dfe:feb8:25f1:ac9c%7]) with mapi id 15.20.3261.025; Wed, 12 Aug 2020 03:35:39 +0000 From: "Tian, Kevin" To: Alex Williamson CC: Jason Gunthorpe , "Jiang, Dave" , "vkoul@kernel.org" , "Dey, Megha" , "maz@kernel.org" , "bhelgaas@google.com" , "rafael@kernel.org" , "gregkh@linuxfoundation.org" , "tglx@linutronix.de" , "hpa@zytor.com" , "Pan, Jacob jun" , "Raj, Ashok" , "Liu, Yi L" , "Lu, Baolu" , "Kumar, Sanjay K" , "Luck, Tony" , "Lin, Jing" , "Williams, Dan J" , "kwankhede@nvidia.com" , "eric.auger@redhat.com" , "parav@mellanox.com" , "Hansen, Dave" , "netanelg@mellanox.com" , "shahafs@mellanox.com" , "yan.y.zhao@linux.intel.com" , "pbonzini@redhat.com" , "Ortiz, Samuel" , "Hossain, Mona" , "dmaengine@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "x86@kernel.org" , "linux-pci@vger.kernel.org" , "kvm@vger.kernel.org" Subject: RE: [PATCH RFC v2 00/18] Add VFIO mediated device support and DEV-MSI support for the idxd driver Thread-Topic: [PATCH RFC v2 00/18] Add VFIO mediated device support and DEV-MSI support for the idxd driver Thread-Index: AQHWX3hut2htBlMVB0qfW0Pa+gZbC6kSPbuAgABwW8CAAzMrAIAUgAoAgAJJ4oCABDO9YIACZAIAgACUIGCAAAy5AIAAD1+w Date: Wed, 12 Aug 2020 03:35:39 +0000 Message-ID: References: <159534667974.28840.2045034360240786644.stgit@djiang5-desk3.ch.intel.com> <20200721164527.GD2021248@mellanox.com> <20200724001930.GS2021248@mellanox.com> <20200805192258.5ee7a05b@x1.home> <20200807121955.GS16789@nvidia.com> <20200811110036.7d337837@x1.home> <20200811203618.41aa6031@x1.home> In-Reply-To: <20200811203618.41aa6031@x1.home> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: dlp-version: 11.5.1.3 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-originating-ip: [192.198.147.202] x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: 3f2dc017-2e19-4e60-b1bf-08d83e70c870 x-ms-traffictypediagnostic: MWHPR11MB1647: x-ld-processed: 46c98d88-e344-4ed4-8496-4ed7712e255d,ExtAddr,ExtFwd x-ms-exchange-transport-forked: True x-microsoft-antispam-prvs: x-ms-oob-tlc-oobclassifiers: OLM:9508; x-ms-exchange-senderadcheck: 1 x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: gDd60CZ2S/O4MxAOvHkLbgsgAAuBTCflVY6RKVymx0yEnK6X3rwkRBGOpyKlA0sSggHR2DFgmUqQ5H7kiK7apDQalFeYPbIQ3Ha5fKM2n7NamBX0nZm8/yKo1qPkUT9gWh466R0YkoocBLVrHiG3ynBKBultsDspX51Dtb/UPjfs0KjAzEQYRYIJmlc+kBsz8o7Gu7h4NwHWvqeBsivaKM6eidJkR84YrSXv9hq/W4Jv9DvX1PYy5kNQY3uCfjUKPImOoJXKdm1ASyOCEdS8PruW8vUsxhNokogA+L8T2zc4D5RlLsoUIa2/9IMDxGiXgBKAxArPmQ4hn1ZWhf/B3A== x-forefront-antispam-report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:MWHPR11MB1645.namprd11.prod.outlook.com;PTR:;CAT:NONE;SFTY:;SFS:(4636009)(396003)(346002)(376002)(366004)(39860400002)(136003)(6916009)(7696005)(7416002)(9686003)(6506007)(26005)(4326008)(8676002)(76116006)(8936002)(52536014)(5660300002)(478600001)(33656002)(2906002)(54906003)(55016002)(186003)(71200400001)(66556008)(64756008)(316002)(66946007)(66446008)(66476007)(86362001);DIR:OUT;SFP:1102; x-ms-exchange-antispam-messagedata: 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 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: MWHPR11MB1645.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3f2dc017-2e19-4e60-b1bf-08d83e70c870 X-MS-Exchange-CrossTenant-originalarrivaltime: 12 Aug 2020 03:35:39.2113 (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: Z4YDs/1+15MIllGJcXucg9I+e6sLBICd1kR6SQG3Y9yQvMi4ZbyNdbnDeXdHwahj6TvZ2CTe5wSI5a92ci0Y+g== X-MS-Exchange-Transport-CrossTenantHeadersStamped: MWHPR11MB1647 X-OriginatorOrg: intel.com Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > From: Alex Williamson > Sent: Wednesday, August 12, 2020 10:36 AM > On Wed, 12 Aug 2020 01:58:00 +0000 > "Tian, Kevin" wrote: >=20 > > > > > > I'll also remind folks that LPC is coming up in just a couple short > > > weeks and this might be something we should discuss (virtually) > > > in-person. uconf CfPs are currently open. Thanks, > > > > > > > Yes, LPC is a good place to reach consensus. btw I saw there is > > already one VFIO topic called "device assignment/sub-assignment". > > Do you think whether this can be covered under that topic, or > > makes more sense to be a new one? >=20 > All the things listed in the CFP are only potential topics to get ideas > flowing, there is currently no proposal to talk about sub-assignment. > I'd suggest submitting separate topics for each and if we run into time > constraints we can ask that they might be combined together. Thanks, >=20 Done. -- title: Criteria of using VFIO mdev (vs. userspace DMA) Content: VFIO mdev provides a framework for subdevice assignment and reuses=20 existing VFIO uAPI to handle common passthrough-related requirements.=20 However, subdevice (e.g. ADI defined in Intel Scalable IOV) might not be=20 a PCI endpoint (e.g. just a work queue), thus requires some degree of=20 emulation/mediation in kernel to fit into VFIO device API. Then there is=20 a concern on putting emulation in kernel and how to judge abuse of=20 mdev framework by simply using it as an easy path to hook into=20 virtualization stack. An associated open is about differentiating mdev=20 from userspace DMA framework (such as uacce), and whether building=20 passthrough features on top of userspace DMA framework is a better=20 choice than using mdev.=20 Thanks Kevin