From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from CH1PR05CU001.outbound.protection.outlook.com (mail-northcentralusazon11010068.outbound.protection.outlook.com [52.101.193.68]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C31D93FFAD8; Fri, 1 May 2026 16:43:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=52.101.193.68 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777653807; cv=fail; b=D3tNDLhD8S44LissSTj+ouD6RcsAzjFtE1/3RMj5wR9+ccA1XaFFO7MH2N9wPomaHBKpAJsOt7tJ9/Z7CuW9fT+Hc5KjbFQQ+ztNF4qaEv94panWUvo78LjShYW6QS3zY9A25uHBDsQoNSxCE5+S7khxR0RoJo0u92nroGSbxv8= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777653807; c=relaxed/simple; bh=sk9aaABRQd5AAVhOEJYhmL+auYmTV8efAXWsZPGB8Kg=; h=Date:From:To:Cc:Subject:Message-ID:References:Content-Type: Content-Disposition:In-Reply-To:MIME-Version; b=nrjj7tEtF9bX7drWLr0a8vrRXweXwyaqhi0UZwVDM88QlscLCEqe3Can8TcbQs7gAFmMoAO57WgdFQmAGJc8zKfEALWZlGBqAYhxqXnam/aBehleexieXH4Fa7biCKbn3TTomFFY455Dh8JmYl4CXR1kcE0qedC1cvhPzGIb8wU= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com; spf=fail smtp.mailfrom=nvidia.com; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b=gI7ZC8qe; arc=fail smtp.client-ip=52.101.193.68 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=nvidia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b="gI7ZC8qe" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=YJ+sSv2XQ/7FE43XCGDIWG2pFckhkDcfkWzqo6wJWrKw2sbRd0RUsqSrQ1f3Gv/3fdKeZff9gz3ik2IbYEGLBaSBmN/NA8RadVqxJg5r8Q8usqHtR3Nf6RqYcKGviajLZnIhjkQSds6+igQ2bvnio4EMpj3SEuA80vek5LFh+wwSi6SwZ3Ax37DDoO09/sIEwF7BZVxGYkz7k1EFprwDycOSSVAmPPOvasEazi58SBPINTr7xo6aUWw6wcE0kBSE4/bu1A+RGn8EJmvBBxHBnTmUZjYsD+QwQSzvLwiKa7/S8yBX+g4b2vk8TrCAwnedMFvkFSLiaNURD4YZTXeRAQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; 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=rVBHX/h2tJHzOIi5eoFpKZibLGe9wiV/sB1WTybCUfk=; b=mGHZ2NHClTrm3mQUp+mHhGy7hvDqmbyrfWrDgPNp5OjTg59S7hdI26mKfb/QAhRqHINM2UGo0d3HP0hi1DY529TxAmFmcCqTb6QODtsGrShbHY18BzvblWy17kvZcOJ61hovBf5B844+TIo+BY5ExFklBhqE/fvcPPSeZ2XFu6+hNjFtZ71MljCAtL92Dwlsuy9/gECPANlwhAk9b1dkGCXCNctJWuth3fsSgS6omA/htH8BUBQNTCwCCUcSEflidHL4B3GRJj2UBSeQS1fnep7QYJdJcGXnwDLKXBEe93p4rdIhAPaeL/q+XkrynAAr5NMkDV++6OTVxnyhQ/cxIw== 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=rVBHX/h2tJHzOIi5eoFpKZibLGe9wiV/sB1WTybCUfk=; b=gI7ZC8qecbQRviWCzbT1BnbaqJ+AfFZ+7qvu0DFlK6jgrNM07KUCb7A/8UbJRRhJcWRld87GxrKHYtLvgsZscw68B50bOPskCSiZw3XDJmQdv11uzLGiXdUZxKT0dbdUjNRM5Q/P6NyF71y4QVFLbtKkG+C6Gl9/Ad1uieYo1LP+hS599+63q8Fyn3T1nwHV9K+VbJduanB9jVyqRpAhTTNH8KBQUMxRLPf/S5xJBAP/qeGn0vBMwKjlQfkbEPJLHLPd0DHapu09v7otsrVqrbC+9zzHXTAWEfjZgPa1RmMRMbDDal2+vfFwgpU/XXCuoZN6TyMve74Qcm51pEcklw== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from LV8PR12MB9620.namprd12.prod.outlook.com (2603:10b6:408:2a1::19) by PH8PR12MB8607.namprd12.prod.outlook.com (2603:10b6:510:1cf::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9870.23; Fri, 1 May 2026 16:43:16 +0000 Received: from LV8PR12MB9620.namprd12.prod.outlook.com ([fe80::299d:f5e0:3550:1528]) by LV8PR12MB9620.namprd12.prod.outlook.com ([fe80::299d:f5e0:3550:1528%5]) with mapi id 15.20.9870.022; Fri, 1 May 2026 16:43:16 +0000 Date: Fri, 1 May 2026 13:43:14 -0300 From: Jason Gunthorpe To: David Matlack Cc: Alex Williamson , kvm@vger.kernel.org, Leon Romanovsky , linux-kselftest@vger.kernel.org, linux-rdma@vger.kernel.org, Mark Bloch , netdev@vger.kernel.org, Saeed Mahameed , Shuah Khan , Tariq Toukan , patches@lists.linux.dev, Josh Hilke Subject: Re: [PATCH 00/11] mlx5 support for VFIO self test Message-ID: <20260501164314.GA1381708@nvidia.com> References: <0-v1-dc5fa250ca1d+3213-mlx5st_jgg@nvidia.com> Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-ClientProxiedBy: BLAPR03CA0104.namprd03.prod.outlook.com (2603:10b6:208:32a::19) To LV8PR12MB9620.namprd12.prod.outlook.com (2603:10b6:408:2a1::19) Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: LV8PR12MB9620:EE_|PH8PR12MB8607:EE_ X-MS-Office365-Filtering-Correlation-Id: 09414d99-7fb9-4a43-d09c-08dea7a0bdf4 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|376014|7416014|1800799024|56012099003|18002099003|22082099003; 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:LV8PR12MB9620.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(366016)(376014)(7416014)(1800799024)(56012099003)(18002099003)(22082099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?VE4yL1ppdXIrNWViZFdrUk1PMnpmN2RackkwaW9seExVQmRqWHN2M29SdzBB?= =?utf-8?B?bmFKV3ZnaGhNbHBBb05RTzRXbzVnZTRnS0F0R2xLTHZMMGxkeHBNN01tZ1JE?= =?utf-8?B?b0ZneVV6VGZDMzFUeUVuWGtQMXd6QSswOFROdlNCMGZNUlNtWnFzU3BvT3lC?= =?utf-8?B?NG9tcWlpdUdEekNKci9RRlhXRWUwYy9palZNN2QzWnJqUUI1dHFwZ0ZWc0Fn?= =?utf-8?B?WjhZTUxZRDhIK1A4NkVsV0R6U3VVOVJETjFGdGlkdGIzaUpoTnZjdDlpMU8w?= =?utf-8?B?YjJFcTRhY0ZLWWRPUFI1dHpwQlRBdUl5L041S2NVc3Q5bDJydDRmcHo5cTJr?= =?utf-8?B?U3JMZGx0Vlg5Z3lCUWRLUVNJYUJEei9ERkZDdUlvMVlTemNiMjd1cWs2RUIy?= =?utf-8?B?V0x1RXBTUE5UVVJMVjBXbGZDdWhJQmxzcTVLVVVxelhraVBJcFJBUFlZN2do?= =?utf-8?B?ZUJkYUMzQzRmV3o4YnZyd2tCWU02U3M4VG1wOTh4SENiYVJ3K1NuVnYxS21n?= =?utf-8?B?VU1KVnNHSzZGaTVIelArYUZXTis4cWJXWGNmc1lwMVVXWmtMSnZHMEV3UW1F?= =?utf-8?B?bnlBRnpPb0xnQ3ArdkpwcDlmQTFKUjZPa0J2ZWFWWi9SQnZRa3UvaTJuT2lQ?= =?utf-8?B?U2ZpNzd6MXFMVHV2TmRVUk1WQ3RadlFudmdFZXpWbkNNdUZoSURLZ0kwY3Vo?= =?utf-8?B?YzRFamlpWmRZSU9VUzQyYjcxNDRkd2kyNHVUbkZma080OU9DSlhPMk05b1BS?= =?utf-8?B?N0FRTVJOZk1YOU05d0M4K0pFRDkxL3MwbWpxT1VYN05FYW1LdWI0VUJ0amt6?= =?utf-8?B?SU9LVGlmU1lDVi9sWlRZQWNYeitta3RKa3lQWmJZZ1FVUFFOdzB4NHJ0V2Qy?= =?utf-8?B?Q3RIREhMSGlyTFYvL1J5dWVZYmcrbGFwaC9ZcFlwSXk5d05MMEJKSlpXdHNu?= =?utf-8?B?eEJNaWhHa0M5ZTJWSmpWb1JGKzdKL24rSjBWLzZMQTR2djlsenZZQTIzUmV4?= =?utf-8?B?ejJEdldrOGQvUkpRNzRVWUV2bGN0NFlSRWFGaENpemRQNFJpMEpaeVdXNHh3?= =?utf-8?B?YnhlUDdheU82aVY5em1sbjVoTHZmTGpqUzhiZ3BXdUdTNzJnMXJVS00rUmNO?= =?utf-8?B?ZjFmVmE5S1ZHcUc4TGZicmc5V1lva0xwbkQ5cnJkUVpjRmkvL0NwdFlPVkJs?= =?utf-8?B?R3BZRGNNT1RyRGJNQUliWGE3b3J4aU5BWCtVL0xiNmp0ak9vZ3MrRktGZm5D?= =?utf-8?B?NHMzRmVhdUpZT1NaTURyanR4Y2dDY0VMSXZDb1VtR3dPb3NJSXZOS291MFVW?= =?utf-8?B?dVRNUlhMTnoyb1N3YkRQdVVpZ2hMZmVrYWcxcVBhN1lJRGM3ZTZ2cGtMTTlo?= =?utf-8?B?REFOQlJQZmZVN2RZamRtd2U2OHJ3Z2xuZ3hneGNSMGRqVUFaS2ZPRHNBUFBM?= =?utf-8?B?clBubFVlRno4VUI1QmVSVk55MVlTZnNOdTFHUDJwODJjeE1odFhmOFNrTlFt?= =?utf-8?B?QXd1bVBNT3NtK1E5aG4vWmdpKytRR0NtTXYveDVzMS9PcnFOQVVRbU1aZ3Zw?= =?utf-8?B?UFhpa2J1WXhtalc4cHhVNjJlOXhDTkdkaEV2ekdzaUgyZEJULy9MUGcxSnls?= =?utf-8?B?OUhpQjdCNWlUci9hT3RFQm9SSmdaTjcvYjYzUk1pMjM3ekcvaUkyQ2YydTlJ?= =?utf-8?B?WDlmc2psM3RaTjE4bmNLRTdQdlRFdk5wMnVpMUxZSkxRNVdXTTNZTXFjSlFw?= =?utf-8?B?UGRXNGpJallCMTl5SFcrTGJaSnhGVWxaQ0Yzb3JFNUtybkJWdk1UcEFWKzZj?= =?utf-8?B?TTZRZVJuWHpFOXQvOENCcHNYcEVzWnZObFZWMEZVN3QxVTMzenVrMGI5ZFY3?= =?utf-8?B?MjQzMEVqSXQ1bXYzUSt2MWZBdnRWT3VCYm10Q2pNSEdEalpzdzZoa0VlVUlZ?= =?utf-8?B?OG40ZHZmQ2JsRDRjVkpxSWJZZ2wva0p2Q3ZaSCsvcVZDZTQram1peklQRFA0?= =?utf-8?B?UkxHUGVZbXNSMG5peHVyOWhKajZiNDVlVGVBdWdhK3h3ckk3aTRWRGRnUmJI?= =?utf-8?B?QWxvVkFWY0lnd3I2NGpBVUU3MEhYMjdvUGNDNy9LMXJnMmJXVmxHRXJwWlVy?= =?utf-8?B?c214aWNscXE5K1psTE9Fbm83bWl4M1c0ME1yOGZyYTFiSkl3djNDbUlzUE42?= =?utf-8?B?MUFRNXJtVEdmV3NRTEw4MmUzc3NYSWlhQnN2NFk2SXBnNmhnb3l0eWRDbU15?= =?utf-8?B?RmlLUHZPSExuTnJLRndXOGxnSjYrMnIvWVJwUXRoMlFMTWNQVVovbGJpVEpq?= =?utf-8?Q?UZ/ayMmnw/vatThVbz?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 09414d99-7fb9-4a43-d09c-08dea7a0bdf4 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 May 2026 16:43:15.9719 (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: +Qp9pH1lKh9ILiB0hCFPLWX3+OdpMvZs8Cpxb80+RVpSvc4FITZwEXyr8SPSTFGH X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH8PR12MB8607 On Fri, May 01, 2026 at 09:11:11AM -0700, David Matlack wrote: > On Thu, Apr 30, 2026 at 5:08 PM Jason Gunthorpe wrote: > > > > Add an mlx5 driver to VFIO self test. This is largely a remix of the > > existing VFIO mlx5 driver in rdma-core. It uses an RDMA loopback QP > > to issue RDMA WRITE operations which effectively perform memory > > copies using DMA. Since mlx5 has a stable programming ABI this > > should work on devices from CX5 to current HW. The device FW must > > support the QP loopback configuration. > > > This entire series was coded by Claude Code in about 4 days. > > Very exciting. Josh Hilke from Google is also working on using AI to > create a selftest driver for Intel IGB NICs so VFIO selftests can run > in QEMU [1]. So it's encouraging to see you were able to do it with > mlx5. > > [1] https://www.qemu.org/docs/master/system/devices/igb.html Yes! I would feed DPDK in as well in this case? Combined with the kernel driver it should be doable. It is much easier if you understand how the NIC works, of course. This worked out significantly because I guided it through sufficiently small steps and knew where to find all the quality reference material.. > > - Make it work on a PF too (this is surprisingly hard!). > > Can it work on CX VFs? We're interested in continuously performing > memory copies across a Live Update using a VF via selftests to > demonstrate SR-IOV preservation (when we eventually get there). Yes, I started with VF because it is simpler. The PF support flow requires a bunch more complicated stuff. Jason