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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no 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 D9348C00A89 for ; Mon, 2 Nov 2020 11:52:42 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 1A31222226 for ; Mon, 2 Nov 2020 11:52:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=nutanix.com header.i=@nutanix.com header.b="uCuYKSbX" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1A31222226 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=nutanix.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:47258 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kZYO9-0001pE-2F for qemu-devel@archiver.kernel.org; Mon, 02 Nov 2020 06:52:41 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:50786) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kZYNY-0001QQ-2E for qemu-devel@nongnu.org; Mon, 02 Nov 2020 06:52:04 -0500 Received: from mx0a-002c1b01.pphosted.com ([148.163.151.68]:13442) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kZYNV-0001AI-9a for qemu-devel@nongnu.org; Mon, 02 Nov 2020 06:52:03 -0500 Received: from pps.filterd (m0127838.ppops.net [127.0.0.1]) by mx0a-002c1b01.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 0A2BpnOU029104; Mon, 2 Nov 2020 03:51:53 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nutanix.com; h=from : to : cc : subject : date : message-id : references : in-reply-to : content-type : content-transfer-encoding : mime-version; s=proofpoint20171006; bh=0D3dJ2nTjT9yhr4SapiKdKMkDDD4oCfVOTwupcU9OrM=; b=uCuYKSbXbrN+iio5Hkm62Z3bUqAG3OZnc1w7tWL9WTEv2OWEfeyhTfJOpfz7WI5nF/xb PukDFp9wczhteHKX8WDpDix6Anzub2xurFukrqZ0ewRmhzCZdQ+5Ry/fP8YvH+X9iOsa YwVPuBU/mfxtp20Nxm5Gm8zgO1CMquYflesfaeR4BSskCjx9RWni//KU+oS8iU1CfLRX uJ4bUI+rlxMvzkA1so/rkRSyXGmgw+bY9xBfkP0omN2J+/Ad7Ok1Pwmy+af2YjNT4Kvn 6yT4K+0bFDo2oA4iuRXs9tEKQaaZ4eWK+YXRnXCeqyfPhSXC1hf7bjpK2YKy8K1CJ8XE Mg== Received: from nam12-dm6-obe.outbound.protection.outlook.com (mail-dm6nam12lp2170.outbound.protection.outlook.com [104.47.59.170]) by mx0a-002c1b01.pphosted.com with ESMTP id 34h7fxk5w6-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 02 Nov 2020 03:51:52 -0800 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=ilbpTHVcAYmMGkV4qvc0w824TF8TTBRxn+7xnGDMTr+TbS9H5rVr99dVZHeTI/iukjq6yv+Y5gohl8i9n5lJ5IuLv6x+sstiEaZEdCLq94WCLmDq24osLRoza6RMurtf21im087GeNEEaYTGY9MGYHl3irldwnugqcLJGnhA7dcz4LZ8UFxL1Nh5cG9YbFTEH7SyrHWSjZwSp8+dKnctBJGRbSyK2tVI9D6K2MrdjkYs+x1NAZwujwqwYFRjJNM/eLHsx5zOrU0O5ES7eEg0misKLitbFwykKm2IEvH+D9xlwv9km7IONfVL0fWEzETrw2UBk2k/+hx+UDfsBUaB4w== 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=0D3dJ2nTjT9yhr4SapiKdKMkDDD4oCfVOTwupcU9OrM=; b=oKdGLnW34pVGuDLpnEZ8R4RJc5WCi/7JOOK90cDgyoWCb61de0rqbyCVIqt3fmt8mvEjYznuaWvXk0kIYoPmq6WeMKUI1r6dm/QMrEQu4ssbgNHeG0F8cDSOrNwGTMPENiQJ5Oj0bqyeiZY0h+Aes8E0Nk79/hoYfDrdvzJZcKdxZGXql9lsjy70jatt1UTA/0776qVZn85vOWG764PYR3uU2GP9tKcqMlmMjnoHsmRV9Rj7jwdy4LpSbshkttto4fv+lHfuuaZCmQnSZ5ZHoQGOKzNOYYNv341RPdRrg5ru0GZLk5PoEgZGhjVoEQNTwefMiJOHzBzdMX0isUrKIw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nutanix.com; dmarc=pass action=none header.from=nutanix.com; dkim=pass header.d=nutanix.com; arc=none Received: from MW2PR02MB3723.namprd02.prod.outlook.com (2603:10b6:907:2::32) by MWHPR0201MB3401.namprd02.prod.outlook.com (2603:10b6:301:76::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3499.29; Mon, 2 Nov 2020 11:51:48 +0000 Received: from MW2PR02MB3723.namprd02.prod.outlook.com ([fe80::81cb:c77a:ef0:84e0]) by MW2PR02MB3723.namprd02.prod.outlook.com ([fe80::81cb:c77a:ef0:84e0%5]) with mapi id 15.20.3499.030; Mon, 2 Nov 2020 11:51:48 +0000 From: Thanos Makatos To: John Levon Subject: RE: [PATCH v5] introduce vfio-user protocol specification Thread-Topic: [PATCH v5] introduce vfio-user protocol specification Thread-Index: AQHWrUTVjUvP5pU8VEG/kGG39PR4hqmtNlfQgAMsMQCABFmqAIAAA3UAgAABbyA= Date: Mon, 2 Nov 2020 11:51:48 +0000 Message-ID: References: <1594984851-59327-1-git-send-email-thanos.makatos@nutanix.com> <20201028161005.115810-1-thanos.makatos@nutanix.com> <20201030170306.GA2544852@li1368-133.members.linode.com> <20201102114126.GA54031@li1368-133.members.linode.com> In-Reply-To: <20201102114126.GA54031@li1368-133.members.linode.com> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: authentication-results: movementarian.org; dkim=none (message not signed) header.d=none;movementarian.org; dmarc=none action=none header.from=nutanix.com; x-originating-ip: [78.149.9.252] x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: 6b7442c1-9863-4692-0cea-08d87f25ae56 x-ms-traffictypediagnostic: MWHPR0201MB3401: x-ms-exchange-transport-forked: True x-microsoft-antispam-prvs: x-proofpoint-crosstenant: true x-ms-oob-tlc-oobclassifiers: OLM:8273; x-ms-exchange-senderadcheck: 1 x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: KzrRbFBq0IhszUiAJlx6nIo4MuDnXpbhZmqPKeBk6/bHSkLKsHdp1sOcYFLKpOlU1ByBraLaizKrcEl4TuH8uJMMpiNu5euseeJq7vxifZEEvIzbRkZnK/4qjSYUCBZH8x78MUq5wtbaT67wMaPMpn0mpbttBK5jF/Z10cpdDbNCHuAoHX8+mQwaxZ8RLgbUjwO4R++7MAN7mxuWaWaUlffb+b2o4vj2514109XCHjFY5Ga1vD5QoGeDnt7BPqI95HhDWeiauEOlsC1UmJFsKCMSQH42FJUn2xfLt+vHAV2rxj+YiIKmHVSwjmiWtltcIeSqaWAYhBAbCerCeOKOlQ== x-forefront-antispam-report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:MW2PR02MB3723.namprd02.prod.outlook.com; PTR:; CAT:NONE; SFS:(366004)(396003)(346002)(376002)(39860400002)(136003)(66946007)(66556008)(66476007)(2906002)(44832011)(9686003)(54906003)(76116006)(66446008)(52536014)(316002)(64756008)(478600001)(55016002)(55236004)(8676002)(5660300002)(53546011)(26005)(6506007)(7696005)(6916009)(71200400001)(83380400001)(86362001)(8936002)(4326008)(33656002)(186003)(7416002); DIR:OUT; SFP:1102; x-ms-exchange-antispam-messagedata: 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 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: nutanix.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: MW2PR02MB3723.namprd02.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 6b7442c1-9863-4692-0cea-08d87f25ae56 X-MS-Exchange-CrossTenant-originalarrivaltime: 02 Nov 2020 11:51:48.6128 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: bb047546-786f-4de1-bd75-24e5b6f79043 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: votGMtatJAUWmv3GWuHCdPFlhVcD+awCRg3N8hC2qXBiX4Lt/dUrOhGjhmutgo8bm0KRMFb+6lS9R6GnGA7+wsu8AThN6X3tnk/rZVlirgQ= X-MS-Exchange-Transport-CrossTenantHeadersStamped: MWHPR0201MB3401 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.312, 18.0.737 definitions=2020-11-02_07:2020-11-02, 2020-11-02 signatures=0 X-Proofpoint-Spam-Reason: safe Received-SPF: pass client-ip=148.163.151.68; envelope-from=thanos.makatos@nutanix.com; helo=mx0a-002c1b01.pphosted.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/11/02 06:51:59 X-ACL-Warn: Detected OS = Linux 3.x [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "benjamin.walker@intel.com" , Elena Ufimtseva , "tomassetti.andrea@gmail.com" , "jag.raman@oracle.com" , "james.r.harris@intel.com" , Swapnil Ingle , "john.g.johnson@oracle.com" , "yuvalkashtan@gmail.com" , "konrad.wilk@oracle.com" , "Kanth.Ghatraju@oracle.com" , "qemu-devel@nongnu.org" , "tina.zhang@intel.com" , "ismael@linux.com" , "alex.williamson@redhat.com" , Stefan Hajnoczi , Felipe Franciosi , "xiuchun.lu@intel.com" , =?iso-8859-1?Q?Marc-Andr=E9_Lureau?= , Raphael Norwitz , "changpeng.liu@intel.com" , "dgilbert@redhat.com" Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" > -----Original Message----- > From: Qemu-devel bounces+thanos.makatos=3Dnutanix.com@nongnu.org> On Behalf Of John > Levon > Sent: 02 November 2020 11:41 > To: Thanos Makatos > Cc: benjamin.walker@intel.com; Elena Ufimtseva > ; jag.raman@oracle.com; > james.r.harris@intel.com; Swapnil Ingle ; > john.g.johnson@oracle.com; yuvalkashtan@gmail.com; > konrad.wilk@oracle.com; tina.zhang@intel.com; qemu-devel@nongnu.org; > dgilbert@redhat.com; Marc-Andr=E9 Lureau > ; ismael@linux.com; > alex.williamson@redhat.com; Stefan Hajnoczi ; > Felipe Franciosi ; xiuchun.lu@intel.com; > tomassetti.andrea@gmail.com; changpeng.liu@intel.com; Raphael Norwitz > ; Kanth.Ghatraju@oracle.com > Subject: Re: [PATCH v5] introduce vfio-user protocol specification >=20 > On Mon, Nov 02, 2020 at 11:29:23AM +0000, Thanos Makatos wrote: >=20 > > > > +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D+=3D=3D=3D=3D=3D=3D=3D=3D+=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D+ > > > > | version | object | ``{"major": , "minor": }`= ` > | > > > > | | | = | > > > > | | | Version supported by the sender, e.g. "0.= 1". | > > > > > > It seems quite unlikely but this should specify it's strings not floa= ting point > > > values maybe? > > > > > > Definitely applies to max_fds too. > > > > major and minor are JSON numbers and specifically integers. >=20 > It is debatable as to whether there is such a thing as a JSON integer :) AFAIK there isn't. >=20 > > The rationale behind this is to simplify parsing. Is specifying that > > major/minor/max_fds should be an interger sufficient to clear any > vagueness > > here? >=20 > I suppose that's OK as long as we never want a 0.1.1 or whatever. I'm not > sure > it simplifies parsing, but maybe it does. Now that you mention it, why preclude 0.1.1? IIUC the whole point of not stating the version as a float is to simply have this flexibility in the fu= ture. You're right in your earlier suggestion to explicitly state major/minor as strings. >=20 > > > > Versioning and Feature Support > > > > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > > > > Upon accepting a connection, the server must send a > VFIO_USER_VERSION > > > message > > > > proposing a protocol version and a set of capabilities. The client > compares > > > > these with the versions and capabilities it supports and sends a > > > > VFIO_USER_VERSION reply according to the following rules. > > > > > > I'm curious if there was a specific reason it's this way around, when= it > seems > > > more natural for the client to propose first, and the server to reply= ? > > > > I'm not aware of any specific reason. >=20 > So can we switch it now so the initial setup is a send/recv too? I'm fine with that but would first like to hear back from John in case he o= bjects.