From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.15]) (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 F36E331BCAE for ; Wed, 20 May 2026 07:12:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=192.198.163.15 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779261147; cv=fail; b=ItFmR5NDS017Iv4ps+VquoU08wu0+IyBrwED13NoUrDVKKiHvDk9oGB4RFQCQSZ2/NdpAPObKJrj0UVv0xINQuhHCaxm6IQhDFYUe1fx1GtuqLqA59NPbGWc8SEObGy7yLzT7owLz8tppuXRsk8Uk5wH/mFiFWpNV5LXwdaGoxg= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779261147; c=relaxed/simple; bh=VP66tOCtR7MQRWnACJWUnuV6IkAiLwu/6qgqk5dgR38=; h=Message-ID:Date:Subject:To:CC:References:From:In-Reply-To: Content-Type:MIME-Version; b=NlCPHXoJqnKCRk4KMzf0cVHoe97dzJh/R9QdOG77r0Pw9q5G5l9hRpTGe/CbdbwX3Z6HMst2v++p3ip9f/1RUyrbECCe/5X+3RwreaJ9oHNNBP+0crS7LeUgkbRPWmNs+cik5XKygiYo2aRcjddFUpoP15F3NuNFBsZbQGS01JM= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=KYFcXsOs; arc=fail smtp.client-ip=192.198.163.15 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="KYFcXsOs" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1779261145; x=1810797145; h=message-id:date:subject:to:cc:references:from: in-reply-to:content-transfer-encoding:mime-version; bh=VP66tOCtR7MQRWnACJWUnuV6IkAiLwu/6qgqk5dgR38=; b=KYFcXsOsnJ1L7SgPap/o/sppeJhJ1+Gs9uS9nRjz2QFduxIgWIz61cUa 7PbL/B2idZb0s5WlOgCeNcnvKhM98HnW+XvfPk9oslrTY8Ms3MmfoB2Xf 2fmnXyy8yTSDJFJcPEIIE0758KWIf/CfQvYWcK4If3KBkAV0OQk9LB0d+ zbO/X5A27cRCuctEQVCNvl42I8AD9fSEikfmFMjZY/Gd/TXcg7qRH5Cxw YTuX4F43Dbb6hp2rJ4ugG0RYkSld/8wTK5DuHxQ7ar+cWrkvExWCUFOXV FC2iYNSWCB1ixc5+oHxNexk+9BtofCp+BR4HjgOcwd+mZf0yyVNXJKpzB Q==; X-CSE-ConnectionGUID: wGD9wmpSRm6RK0z1Is8txg== X-CSE-MsgGUID: 7SuXNzs/Th+ghTLA4+B8tw== X-IronPort-AV: E=McAfee;i="6800,10657,11791"; a="80268319" X-IronPort-AV: E=Sophos;i="6.23,243,1770624000"; d="scan'208";a="80268319" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by fmvoesa109.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 May 2026 00:12:24 -0700 X-CSE-ConnectionGUID: 4nXFZHbeSGChSlc4KIgVUw== X-CSE-MsgGUID: JONdsLccQ0+runl4mJWorQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,243,1770624000"; d="scan'208";a="237070992" Received: from orsmsx903.amr.corp.intel.com ([10.22.229.25]) by fmviesa007.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 May 2026 00:12:24 -0700 Received: from ORSMSX901.amr.corp.intel.com (10.22.229.23) by ORSMSX903.amr.corp.intel.com (10.22.229.25) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.37; Wed, 20 May 2026 00:12:23 -0700 Received: from ORSEDG902.ED.cps.intel.com (10.7.248.12) by ORSMSX901.amr.corp.intel.com (10.22.229.23) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.37 via Frontend Transport; Wed, 20 May 2026 00:12:23 -0700 Received: from BL2PR02CU003.outbound.protection.outlook.com (52.101.52.60) by edgegateway.intel.com (134.134.137.112) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.37; Wed, 20 May 2026 00:12:23 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=XsY3HLQWWZ/6GURw/RILkznYxIHgO1DaNloi5G2ugAYIjnRRrYrWM4ocHZZZtFNswmBSf4e3IdQl7kTCipfW0Qe1ww3c0AjIOEeZA5K1wM6UpIU0Nv9pOm8D2DaP8ENirig79zmaqva4kiPNJ7eNbnu8x2IIqq/q1qy3T9GFLPHDMse1KzbIHITPw2K+9IYo2T6GNwhHMfujQO4KDg+8Y+VhnXj7AFRxY49tDhQ3D+uDZSBpCiFtvkLddNeuC4XhThBM5Th9zAXDHJ00VoMAj/x9p8BTyNeShpoHgoW0L1n/4KZSOFCl6cp4dhbo63FusNJ0GwGq5xUkKyZjwMvstQ== 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=/TxK3hW115abCJ8Sl3ssYV24xX6rSBGTGLq74W0/9kw=; b=Ak0xJ1MZfc+aDpckaWqvJ8z9LytSdfA9ETh/OANdKvcvNB4bv9W5yo6Wq9JTVHUD8yCeFDWKiEjNhtLFuY94gJwzh5AJwC5fIrSjPY5mBowQ3XtGhZkqjlIYQU8e7YKOVyoiS8rORmUdDkxYRaG1eDk69JTt1tsH6c5I3kkuSnhh3L0+sxLIaGLsh/eQ3xccscccqyZsXwjiR5CRROIyVJ9QYU68H2zZKcm1B+QxxQaAmz2selzPEEfdnvmLBlNwtfvaFXhSInqpQSQF90vX8VcXkRUCkyQUugjBUlralCY71tpWvauF7JEWqNwcAvs9NGU5k+oRMWybuzc8Y8lDEA== 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 Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=intel.com; Received: from LV8PR11MB8509.namprd11.prod.outlook.com (2603:10b6:408:1e6::15) by SJ2PR11MB8424.namprd11.prod.outlook.com (2603:10b6:a03:53e::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9913.14; Wed, 20 May 2026 07:12:21 +0000 Received: from LV8PR11MB8509.namprd11.prod.outlook.com ([fe80::f5bd:4dde:4f2f:20b7]) by LV8PR11MB8509.namprd11.prod.outlook.com ([fe80::f5bd:4dde:4f2f:20b7%5]) with mapi id 15.21.0025.022; Wed, 20 May 2026 07:12:20 +0000 Message-ID: <19f8ef7f-2935-45e9-8139-4d7030629f49@intel.com> Date: Wed, 20 May 2026 15:20:30 +0800 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 9/9] Documentation: Update VFIO NOIOMMU mode To: Jacob Pan , , "iommu@lists.linux.dev" , Jason Gunthorpe , Alex Williamson , Joerg Roedel , Mostafa Saleh , David Matlack , Robin Murphy , Nicolin Chen , "Tian, Kevin" CC: Saurabh Sengar , , , Will Deacon , Baolu Lu References: <20260511184116.3687392-1-jacob.pan@linux.microsoft.com> <20260511184116.3687392-10-jacob.pan@linux.microsoft.com> Content-Language: en-US From: Yi Liu In-Reply-To: <20260511184116.3687392-10-jacob.pan@linux.microsoft.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: TP0P295CA0048.TWNP295.PROD.OUTLOOK.COM (2603:1096:910:3::19) To LV8PR11MB8509.namprd11.prod.outlook.com (2603:10b6:408:1e6::15) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: LV8PR11MB8509:EE_|SJ2PR11MB8424:EE_ X-MS-Office365-Filtering-Correlation-Id: e67b6f61-40de-45ee-ec42-08deb63f2225 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|42112799006|366016|376014|7416014|3023799007|921020|22082099003|11063799006|18002099003|56012099003|4143699003; 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:LV8PR11MB8509.namprd11.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(42112799006)(366016)(376014)(7416014)(3023799007)(921020)(22082099003)(11063799006)(18002099003)(56012099003)(4143699003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?TGsrWkJjYVJIUUdubGxQcXdWam9RTjBtdEdWcVNpbythczhSMkkxNWpQaElx?= =?utf-8?B?akFPbWxzcjNpZ0VFUDh3L2RVZnBnNWI1RnF4dHVYSEQxbUc5RGt2SVVXWHpq?= =?utf-8?B?KzhtZ2YrVjRGMGRab2JJZ3MvaEtMaEgrQ1BkcUJGYmJtMFUvOGVsVXdxSndY?= =?utf-8?B?VHFuaWQ5bDRieU85cE1yVzZzTktqbXJKM2pCTXNTUElYYlJKbjZjSnFzamha?= =?utf-8?B?SnlML1F2bDBiSVRHNktHYUdXdUtMVm1URTg2VzZLZnc5SGloamFFekFaUjJQ?= =?utf-8?B?cy96SjhlYVJTaFRxcEJsbFhIaE9sWDJwM0t0S05YdnJtczJtaDVuYVVwUExq?= =?utf-8?B?SjFyL256QXpIem5hYWRnMEFBd3Uxbm5kOGJ5RFpVNkJUWk1obUpEUDdxdDk3?= =?utf-8?B?dTFmWUo5djZpMVNFc2w3OExWWlFSN2JNZFFOWmJmZTBzT1JMZktjc0ZXVHQx?= =?utf-8?B?YXY5enM4MlN6eUlKZk43SzA4NU83UnYzTzVLZmhZVk5vYnBJUDNLbG9MZXhs?= =?utf-8?B?OHB6MnM2K3VuSnJXQmdZcnp6ZzkwZWJiNW9FUW5DUGhQZGgvT1BaQkRHYy8y?= =?utf-8?B?bHJoVjdiN0R4MWhrd2VMTytETDZrb1RvQ0U2S05IaFdVLy9hdUZpN2tiZWFT?= =?utf-8?B?SlFxQkVteWJlSXZmcVUzZTlZVEl5UnZneWU2Q05NeDJtTE02RVVQbTRYL2Fa?= =?utf-8?B?eWJSSnYra0txVTdTTk8xV05TckdnT2hWYzBWc0RVZDlYU1JXYVZ4TEpyell6?= =?utf-8?B?M2kzaU9KNVp2RUZTcGVueHhnYWw0WWRUaUlHZmg5cWNRUVlaUFVSaktMQzZK?= =?utf-8?B?UHNtNFFpd1ZzeWViRWRuTkcwbkkvT2t4MHVMelhXRXBCODBSMlEzMGxCZWxB?= =?utf-8?B?a3FXNDc3aWE3QVBDNHQyZjNKZ3NZV0ZmRko5aHVpRDIrVmdlWEVRdkpsQkxo?= =?utf-8?B?MGhVTVhTSUhTWlorRSt4bWg4YXE1a3VuNE9aaHd4d1F5VVJHSFpIdXd1WnY3?= =?utf-8?B?VzhFb1dQcmRySVE0YklKSGplTmYxVngrdWx1OUhEMFNMSTlDa0crdVE0YVNH?= =?utf-8?B?ZVF4bUI0TmJudmFJQ0lITXV4M0E4SEFZZWxFTWxrT0RJZWt3ZDBGbWkvNUxn?= =?utf-8?B?VWJUN1ZGQ2kyajVzeW54RU1VaXVpSlZxL2VneE9CUDJ0Ulp4OG0ybmI1b1Bz?= =?utf-8?B?eU90WG5ybW9LT1JvNzF6NEtXWGJpc0JRMjJnZlY1WHBwbFN4Z1ZERCsvR2NM?= =?utf-8?B?N3VIenY5YUxwVW43aXFiOXhOMjJkSjgzMDFlS0JkdHhIN3o1c0dMbUt1TTho?= =?utf-8?B?RHJtVnFMUlFoZXZLc3RkcjM2VVFFaXBCZlE4RmIrMHhobnlsS2o3ajdHYTNM?= =?utf-8?B?TXVTVmRFNndQY1FTMThPZzdQZk1QYlZ6WnNHb280TnhhbmtseWlkbkVYUXVr?= =?utf-8?B?REs0REx1aWo3d2hNc1FpOTZOdytYa3ZBVDlzWk16OFlCS0hobWQ4SG9GdU1G?= =?utf-8?B?S3Y5M0M3NUR5aW9lRk9ZVGdUaGtnQ21BNHdwVndOc2I1eUJ4L1Z4SjBMd0xT?= =?utf-8?B?YmRDRmQ2N3JHSXlBUmJ3Z0ZaOWJLbWljSW1OZzkzY0VKY3Yrd0N4RFFBYUMx?= =?utf-8?B?a0hmVDZHRktBaTNCbGEzcHUvamZFMFVSV3Z1OTl1ano1UEZhNm1waGl5UjMv?= =?utf-8?B?bnJNQkxRRUFnZllpV0NiMFVPbElxemc3RC80SmJkQll4SDBhaDdDUWZtWnE5?= =?utf-8?B?eXMwOGdNMkd4REE4RHkrdVp3dDlsTUZBajkrUEV3K25LcklMTWlUbzA1MHl2?= =?utf-8?B?WjNieWdKaExPZlBPVU1IREM4UHVCM1o1U2lndlkzeGlrWnhoQ2x4eHRwL29D?= =?utf-8?B?ODgyS1pFcVhzbHZkcTZTVHJXQzJDMGM5R0tpa0hyQ2FKcTRIVUlTeHlFRmlR?= =?utf-8?B?dnlXeUl4MkYvTTFVS0cwcFpkeitJUVhvU3NGb0lLQWFmLzkxMVhBcGR5QnIv?= =?utf-8?B?c3ZDTkdlTHkvQnR0T2dRV1ZjeDVaK0ovS3JLTEVBbW1YQkh3N0VFQlNRS3l6?= =?utf-8?B?YkJOQ2U0SEFBK0Z5c1NmUytyV3ZUVTZMdU1wS1RSV3NyRXRKRzFpNzhaU1pr?= =?utf-8?B?SWp3MUVQbCtVZDBUdndmcCtzQTM4ci9CbUFMS2I4Nmt6ZFFDeFhrMWRxdEFm?= =?utf-8?B?Y3VzQXZKd0NkZ0NlRHc4MURLazBWUlYxZ1N0WWlNVGxnVGoxU2l6UFVrWmE5?= =?utf-8?B?VmZKc1hDa3JLdGpNQjZBTzRNbmx6L0prbE4rald4UXlOV1NTQmxjNWRjODQy?= =?utf-8?B?ZUlqNWdEc1NldytuQkpDT0Nhbm5sN2wwbkI5OFlCWDFRV0k2cmRudz09?= X-Exchange-RoutingPolicyChecked: XrN82QHPdtaR+o0Hfsv9KXc85dnuBw057095S69OS3Pz9Dd7AbjAFkcoKP9cdFlLJM4BU3l9slIShd5RoK0zHOez5J3rqt6HezpJ6PwIJOvZdjalPebwjT3Xan5wgvPe6V1/xmGidTsvxE9p32puAkpPcQCUOl+KRfHOSNaPkIoEHxk2JlF+SQUp3dzLmf33C2BCfz6wkkY4Su2n0oVd4cb1JdZeW3+8cUozg4XkIGwexwQsa4w9Q7uYiLZ6XeSejElvKp5BAQo5GvtuZLK05cAov+6eqX89JtW9iDqbcdEESXvR0x5hCSZaC6z2zewKUrJ0hiKPZX2P6MxUXZ8VMg== X-MS-Exchange-CrossTenant-Network-Message-Id: e67b6f61-40de-45ee-ec42-08deb63f2225 X-MS-Exchange-CrossTenant-AuthSource: LV8PR11MB8509.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 May 2026 07:12:20.8236 (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: HILdyN7rYIYiyXRZkQ4y/v8PaAwjXoh/iqd/atWNM6fyUkoP2zGW5Hr/KeMcnZXy1cOxKSvBqY4Hd/1Ynh9zLA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ2PR11MB8424 X-OriginatorOrg: intel.com On 5/12/26 02:41, Jacob Pan wrote: > Document the NOIOMMU mode with newly added cdev support under iommufd. > > Cc: Jonathan Corbet > Signed-off-by: Jacob Pan > --- > Documentation/driver-api/vfio.rst | 46 +++++++++++++++++++++++++++++-- > 1 file changed, 44 insertions(+), 2 deletions(-) > > diff --git a/Documentation/driver-api/vfio.rst b/Documentation/driver-api/vfio.rst > index 2a21a42c9386..d97017d80b98 100644 > --- a/Documentation/driver-api/vfio.rst > +++ b/Documentation/driver-api/vfio.rst > @@ -275,8 +275,6 @@ in a VFIO group. > With CONFIG_VFIO_DEVICE_CDEV=y the user can now acquire a device fd > by directly opening a character device /dev/vfio/devices/vfioX where > "X" is the number allocated uniquely by VFIO for registered devices. > -cdev interface does not support noiommu devices, so user should use > -the legacy group interface if noiommu is wanted. > > The cdev only works with IOMMUFD. Both VFIO drivers and applications > must adapt to the new cdev security model which requires using > @@ -370,6 +368,50 @@ IOMMUFD IOAS/HWPT to enable userspace DMA:: > > /* Other device operations as stated in "VFIO Usage Example" */ > > +VFIO NOIOMMU mode > +------------------------------------------------------------------------------- > +VFIO also supports a no-IOMMU mode, intended for usages where unsafe DMA can > +be performed by userspace drivers w/o physical IOMMU protection. This mode > +is controlled by the parameter: > + > +/sys/module/vfio/parameters/enable_unsafe_noiommu_mode > + > +Upon enabling this mode, with an assigned device, the user will be presented > +with a VFIO group and device file, e.g.:: > + > + /dev/vfio/ > + |-- devices > + | `-- noiommu-vfio0 /* VFIO device cdev */ > + |-- noiommu-0 /* VFIO group */ > + `-- vfio how about noiommu-vfioX and noiommu-Y? Just want to deliver the message that the two number is not 100% identical. > +The capabilities vary depending on the device programming interface and kernel > +configuration used. The following table summarizes the differences: > + > ++-------------------+---------------------+----------------------+ > +| Feature | VFIO group | VFIO device cdev | > ++===================+=====================+======================+ > +| VFIO device UAPI | Yes | Yes | > ++-------------------+---------------------+----------------------+ > +| VFIO container | No | No | > ++-------------------+---------------------+----------------------+ > +| IOMMUFD IOAS | No | Yes* | > ++-------------------+---------------------+----------------------+ > + not quite the above table. Why 'VFIO container' is "No" for VFIO group? > +Note that the VFIO container case includes IOMMUFD provided VFIO compatibility > +interfaces when either CONFIG_VFIO_CONTAINER or CONFIG_IOMMUFD_VFIO_CONTAINER is > +enabled. > + > +* IOMMUFD UAPI is available for VFIO device cdev to pin and map user memory with > + the ability to retrieve physical addresses for DMA command submission. > + > +A new IOMMUFD ioctl IOMMU_IOAS_NOIOMMU_GET_PA is added to retrieve the physical > +address for a given IOVA. Although there is no physical DMA remapping hardware, > +IOMMU_IOAS_MAP_FIXED_IOVA is still used to establish IOVA-to-PA mappings in the > +software page table for later IOMMU_IOAS_NOIOMMU_GET_PA lookups. > +tools/testing/selftests/vfio/vfio_iommufd_noiommu_test.c provides an example of > +using this ioctl in no-IOMMU mode. > + > VFIO User API > ------------------------------------------------------------------------------- >