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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 85AA9C761A6 for ; Wed, 22 Mar 2023 12:18:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230361AbjCVMSj (ORCPT ); Wed, 22 Mar 2023 08:18:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46244 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230288AbjCVMST (ORCPT ); Wed, 22 Mar 2023 08:18:19 -0400 Received: from NAM10-DM6-obe.outbound.protection.outlook.com (mail-dm6nam10on2072.outbound.protection.outlook.com [40.107.93.72]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A59F9442CA; Wed, 22 Mar 2023 05:18:03 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=CY0DElOamp8L9wlpzinF0lzas/AZAjy8sHB++U4ORXDjUIQO27Zljs8+0fdpYwqDaGfpZGwb/YrDv+cf9huiCf7hDnH5MapRMx/1i/Ey2QMT5UvMd4U6mbCiYi6huq5GhzQWPDlXWjO1zapRBAOOxmEfu0EIhsl52MVDLqcaSw6MEL/IL18xnS5UFkm7AQfOFBrjHV6ax1pMMkDcCSNPV23VPVMq2GfNNtruF/Byc0Emn4aoA3jc6mZclxwcET6kSedCKXgrZl4CNM2XwM+1ZQseo7/Y28m5Haw18gHXR5/4xoyUTcAog8RAIop8spCO702WiztaWHhfHgBiTXMLyQ== 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=W17RT99oW4AltTfUDOZ2wl9KZ2h+4pYPTEpd/1aB838=; b=BSykMD+zgUB8rgNs0gre3dDnNECu5jMafn3E35fgAewVu0N5QB/K1hjw2xZyxpbFpZ4wjqiC91JTqy+Kmzp/3ND18xptnR93O2rwxe8d4egPPwJkazhQPLw+7fmoYQncC9DPqWrFJsvzv3qE4+Vns79SG1BfKd7VSSBO3abcs86l0j4oINzULlCQ0DlE03ZsQYO7zrjZkPMFRfRvsSKAqDHXW2yhV4KY9qRh3MhCUfLORQEAgUDoh0wQVtfmOfOCIQY+NyMa1dFPPVn3NF1hObDXegOZ488BOUUTTf+gCGDmPZM7unZPAZAB1rQPVPgoHUZWb8KQ1mXBhfY4IOcVVQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nvidia.com; dmarc=pass action=none header.from=nvidia.com; dkim=pass header.d=nvidia.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=W17RT99oW4AltTfUDOZ2wl9KZ2h+4pYPTEpd/1aB838=; b=nvDp+W64yQjq3hnpfyyaNxo/GdB3S75WHvB2fgvHdOEZo1mMW7FfJ81KKQTl7EyGfKoERnCpI6fgABIyvCooESUQZD0wtPW810R3BEQ8UQGgFRII3zABOObIrvSdpDXcBL0Mc78ULAbtwZR4C1Xr5WNwZIZcqK6r5wqTTLRnzH7fz0EqxTIaRxQ5JhFnbccwJl2m1LftgU8uKipuJcd7QfgJ021WTu3gcu+C4uUe0EK8Gylb4hM7BPHJJChslfat9nDY5fXzhpgERauw24U1+dHLyzP/O7eyNir9/sDmtqhI3K11SMOr93iFkVM3/ByIv6iJaUf2m/OsYgkZ+GwHbA== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from LV2PR12MB5869.namprd12.prod.outlook.com (2603:10b6:408:176::16) by BN9PR12MB5081.namprd12.prod.outlook.com (2603:10b6:408:132::22) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6178.37; Wed, 22 Mar 2023 12:18:01 +0000 Received: from LV2PR12MB5869.namprd12.prod.outlook.com ([fe80::ef6d:fdf6:352f:efd1]) by LV2PR12MB5869.namprd12.prod.outlook.com ([fe80::ef6d:fdf6:352f:efd1%3]) with mapi id 15.20.6178.037; Wed, 22 Mar 2023 12:18:01 +0000 Date: Wed, 22 Mar 2023 09:17:59 -0300 From: Jason Gunthorpe To: "Liu, Yi L" Cc: Alex Williamson , "Tian, Kevin" , "kvm@vger.kernel.org" , "jasowang@redhat.com" , "Hao, Xudong" , "peterx@redhat.com" , "Xu, Terrence" , "chao.p.peng@linux.intel.com" , "linux-s390@vger.kernel.org" , "mjrosato@linux.ibm.com" , "lulu@redhat.com" , "joro@8bytes.org" , "nicolinc@nvidia.com" , "Zhao, Yan Y" , "intel-gfx@lists.freedesktop.org" , "eric.auger@redhat.com" , "intel-gvt-dev@lists.freedesktop.org" , "yi.y.sun@linux.intel.com" , "cohuck@redhat.com" , "shameerali.kolothum.thodi@huawei.com" , "suravee.suthikulpanit@amd.com" , "robin.murphy@arm.com" Subject: Re: [PATCH v6 12/24] vfio/pci: Allow passing zero-length fd array in VFIO_DEVICE_PCI_HOT_RESET Message-ID: References: <20230316182256.6659bbbd.alex.williamson@redhat.com> <20230317091557.196638a6.alex.williamson@redhat.com> <20230320165217.5b1019a4.alex.williamson@redhat.com> <20230321143122.632f7e63.alex.williamson@redhat.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-ClientProxiedBy: BL1P223CA0004.NAMP223.PROD.OUTLOOK.COM (2603:10b6:208:2c4::9) To LV2PR12MB5869.namprd12.prod.outlook.com (2603:10b6:408:176::16) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: LV2PR12MB5869:EE_|BN9PR12MB5081:EE_ X-MS-Office365-Filtering-Correlation-Id: 651c306c-5485-4511-4087-08db2acf7ada X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: UxlGkZOZc07Ge9ij8F5hVbV7DWyI5wcrZQDiUmx7mSUox2520Ykzzx3Tx00FK7d/NmDWHRifNimms5VD73R3E61cHmr0QAOF2lvBfNhaCHUoO9olQA8O/TAVuZqbRSFWeS+qvD2cn4O1BHQtbxoJPKASQ3iwlEz97/fkIMd3NPaZnIA9HAJXdBSDUvn8A9sOM7sMQwsMYfJcmNiFk8GUzFBLizOmsimCPkytyROZLwBtGn+7QfIW6Nk0qx66hscKLBlxHprP1BuW9x2iBqaTR7vxb/Ae4/r/ZzDkuPkcnLjvT6y5guJMPCFmY48pcvoqIp5v87otRmHWdCKq19hqoLE9kspeMOnDW/MUZA5MuTVGvL1xmN+6YbelTLL/evyVyVLk4er1Pf0SxwB/wDbetKWRJqrRIsgNUC9A2e0uTAd50y63JlyGAT5Kd4f9K1L9E9RP+xGqc3rs/R3dJ3gm0EjxBfn2OF86m//JMGZA82d7gkKOR+BSHgHes+B91unNzLt4LImvFuxxLrKKlXVR2IbU3WtzMnuFLNdrVbgCH9UNGPqnaQATnQVVXWrBP519UZnQe0+0GGr9ES7ny9uYiFvOB+9aEuKF07Q7fVhomEn0v6u+ycgkSjU7OQVWfmqRB0QXqx/IsXLSVu43/6sXjg== X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:LV2PR12MB5869.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230025)(4636009)(39860400002)(396003)(366004)(376002)(136003)(346002)(451199018)(38100700002)(6512007)(5660300002)(4326008)(6506007)(8936002)(54906003)(41300700001)(6486002)(86362001)(316002)(8676002)(478600001)(6916009)(66946007)(66556008)(36756003)(66476007)(26005)(186003)(2906002)(2616005)(7416002);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?cjMXit2F7X/o/tnZC2sYtf/Cd+S40cjb1MS0gvWaXFtZ+BPbdaiwYRXK2rk2?= =?us-ascii?Q?KZYfaRnRX9ui03PtlWl2rgy7MrfsB+pBTz0jTBYp7GhqIqvjU20GmHQ7KJzs?= =?us-ascii?Q?m+ZqmGgCvZiuWScYIwWni7KTwNW/LM4Dc5tbqQr/Idr6FrdGpcYv9mXXapeh?= =?us-ascii?Q?rbXJJ1c9STBP2SIY17MwuxW+dsabY8t61FXA5ohfqPRReTjXCW2zJ3b3IWPg?= =?us-ascii?Q?bxFCZ5lnTJZrLspOreG9xVux5G73mh32XV2sj9UrDMyCGNO9CFV3VT0YEwrd?= =?us-ascii?Q?j7orX4IRjdAX6PHv5RbhSEHl0oP+NeUDT7u4GKgr8Ktni0K0WMN4ZKXnCAKt?= =?us-ascii?Q?KSFoyu3yNYRbUEkXWKe3N27Z8whj4ZG/NRsZJETbn13thU5dNf2FrbiIDW8g?= =?us-ascii?Q?+c3kw2zl2mDZDalu/2G5tV0GMJX53Sgr+omjhLAj41PSkyIx9wYx4oKa2nkz?= =?us-ascii?Q?nnZ8nsapRGf7dYM/t/UwhPjOCcmWMrrTYetdstwm2+cyH80Z+GPoMBzkwYru?= =?us-ascii?Q?MIK7ztLPqjmac/gql4LyMTQ8EzSV/LAd3AChUJ1JM//1ZUwgJYTExBpYfI9f?= =?us-ascii?Q?JUNS0/Kd5NCEXKuP9KeB7e1oME2oG0acj9STbCVIotapukzJq3Fc0VT+dbRI?= =?us-ascii?Q?1+LuDOZDb0PEKx8+AhVYkdfcJ8BtNlDRG22wAdhdS69fKunX6SvWDXkTALce?= =?us-ascii?Q?HIlsjjtx5QE9mKVCpZas3HXRWIvAezyi/fSaqTLPR6wYVex80R8JdB7Vq9eq?= =?us-ascii?Q?AL9do4pKG0u74ETQT91bSzazIbWMNGislYQSOSCbo0O9U23p8kii1hcZjutT?= =?us-ascii?Q?ScRw6ukbUWVUgieo5E5702R5W7k5iwvwGU2FWU218Y42+3o3IYWv/j2hg6Rk?= =?us-ascii?Q?9FLmbXoF64CznE6fVioFWA9WWSJ7i804EgpQAUO0HhMbrHoiQPlKdmL7kUPv?= =?us-ascii?Q?bRqlNiOGuamlFmWh1HdQZ5xQWfl2nInZHmx1ED699VrRvhB28wEJcB+qN9TP?= =?us-ascii?Q?kxMKziAzMGAHUQI3gMvVZGcJqZfGwFBQgbpVdyLcQMtiBEvWrPoYjUonzj84?= =?us-ascii?Q?6y/WuLAV38fZvbzGXgDeTWWk+bMsZVsuzORVDW3S5MWWiHMlPoCR0MJGU74j?= =?us-ascii?Q?IKIWUIBmHAOv+BD5l//sTnEQumg7IedR988BN+RmI+8Q9fJpXD0rww1Aa34T?= =?us-ascii?Q?feYqKDqtpYRzEuCfaYm/OKdVJ5KZxdWwa/d6tV8CSU9HNvMgEXnkUDU0Zb0r?= =?us-ascii?Q?lzbdwGNYv2utqav+7pKW6OpkND6yfNsBmaNTxglNKTqllTjXcBvAmpQIexQI?= =?us-ascii?Q?KCiyRtnBX23W7cAbPDIIC3qJOSATaYOFQEaEp0eIlp93ji4Y9HOJtJXbTKmd?= =?us-ascii?Q?1ZH7iAMyzH9t7Mb4IuYQcoNFFd7dR6UaNBt1I5UchKpgsaf0XHiIOn+DeJsL?= =?us-ascii?Q?6zIkFhyzue6F8cUk/7nPsX8OaGKIC96PVjb/zcQmKRlMg0YG2rrEaNgrCBhf?= =?us-ascii?Q?IjuCL9lPn4yHm3nDO4QA73RCEITOJXyoE9ccPTe53hrHsIbjOssBmeJvcH/i?= =?us-ascii?Q?ZRX7hJi+NDBJVaOw+HpbMilFRv8XvguLZbFW105v?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 651c306c-5485-4511-4087-08db2acf7ada X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Mar 2023 12:18:01.2808 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: Hevn6DjFDrlpb0n+qqbe/rZ59Hey0KHyqOrYqkQql5ZYUkIhjIUsOmw8O8rqeWtg X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN9PR12MB5081 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Wed, Mar 22, 2023 at 08:17:54AM +0000, Liu, Yi L wrote: > Could you elaborate what is required with _INFO before libvirt can > use a FD pass? Make a new _INFO that returns an array of dev_ids within the cdev's iommufd_ctx that are part of the reset group, eg the devset. qemu will call this for each dev_id after it opens the cdev to generate the groupings. > > But for the current qemu setup it will open cdev directly and it will > > know the BDF so it can still use the current _INFO. > > > > Though it would be nice if qemu didn't need two implementations so Yi > > I'd rather see a new info in this series as well and qemu can just > > consistently use dev_id and never bdf in iommufd mode. > > I have one concern here. iommufd dev_id is not a static info as much as > bdf. It is generated when bound to iommufd. So if there are devices that > are affected but not bound to iommufd yet at the time of invoking _INFO, > then the _INFO ioctl just gets a subset of the affected devices. Is it enough? I'd probably use similar logic as the reset path, if one of reset group devices is open and on a different iommufd_ctx then fail the IOCTL with EPERM. Jason