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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 89DD5C0218D for ; Wed, 29 Jan 2025 20:17:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:MIME-Version:In-Reply-To: Content-Type:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=V2R8leLWx8ZHkLIBCyMsCcXhS2wKaRukmEZagptH4wE=; b=I/pUUfxay/kNpvJ9x9nNB7KRI9 5t/sciOi8zmJN4HsOmUoa4rCBgm/jKCCrN2UJJu4WvZ6NLjVAqkIj4yOMQFE98wx/2hMCB2/Poe1H LfbXDJ+anhGMhNfCZ8sruP/q7jBKHY9Wlgy+xXXwYnuw9Of1miJWskO1wmOk+dAXSuJMZJ+TEp/HO iNE0KoowbbAMDzrEcyZSP7wBFhH3XYbwGBv2zhg8iECnfNw9NKSgypoEMO0CzYiPWNQMRIqXThRFv OmdNhDZ0aFPMFZCzhSYGjwb+HRMJS12CvuuSBIdFdoLf17dvw6EQ9B1U0l6bK8mxKpBY5wEc8pcE/ ykgkYq9g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tdEV4-00000007kSe-22g5; Wed, 29 Jan 2025 20:17:26 +0000 Received: from mail-co1nam11on20622.outbound.protection.outlook.com ([2a01:111:f403:2416::622] helo=NAM11-CO1-obe.outbound.protection.outlook.com) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tdETi-00000007kNF-3xir for linux-arm-kernel@lists.infradead.org; Wed, 29 Jan 2025 20:16:04 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=cstfM74OVCZlpSovVQt2wQ+1DfroS9s8y8xOKEoouaHOn4HnQKvR/4IX1lumR4QQdfZI8lQ0EV8JhIFN2axTA++fBgz/T9P5EQLnxLk5fhrKamEFsmndCQAxtiFRQPa+gziUh82096y53ZmnoWeQE5quUnQh8jmOmC/94+dLMJxCWvZx0jk4D8X0acPY8KZaTQMt+LGdJWTl/onifKJt2hAhSlctjSueZYncrkAdiUFXzf0u4dVWGmMop+U4h5Z3TKMKVK5GHGquG0Pq377LcWvBdxWKFXr7DZZ+vMcmBu+8tmjcVlumt2+cMeuQ5+OrOH7KVoyHlL0X3i2cCPga4Q== 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=V2R8leLWx8ZHkLIBCyMsCcXhS2wKaRukmEZagptH4wE=; b=NunMYU7/nrvtbNtv4VOYINfLVN1wA1hUv0uDQeqMt7QCCSOjPn9/9DO8C20l9IHsBmzj0RTXLpFwgNTsawzMSh6LXkaW268WFKFbYIMCKCgbNSoAOJCwbL5w5jjrvc5TXPMXgg7Yrs2HOuYIzmIhVgAWmA0xyiIIjWSaezozpxnqBXQ0E8PJW/XVgpdhF5I6dOBubl7ALSihZPF5rxdnjwzJKgZfZlaylw/6GcRjeIAWbtVKRvIRfXM+BylVA6WCmuxOv66xPjyBsNQ84Z16dcVz/BMK2yzwBfXrG+KituSYSs8FXgvJS15itr1lv1rhNmCAv8pk0p2IGWLY824ifA== 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=V2R8leLWx8ZHkLIBCyMsCcXhS2wKaRukmEZagptH4wE=; b=B6pf27GcZTry+7LtKPhEItrg6LyhOBquHKwJ9uHK7+D6ERym1su5r2YzZmpBhLYBIFa2u+LaKRVNLG+JMr+7UogIiX5FqXLrR71g6IK+kpaam6Ahz87QRjwgcVCK6hferlpe9uXkmUNHo9+zLf1lD3MOlx9UGeQO8gRYxex5U6nCXFZlS33MvumWO5D71BddXOu1Bvtaoa+tVVZkOP00g1UAA/YZgW+fMq5pm5EjpGBxVhrwXH74PU++TXXl30fx1H8yDHJ4yVPYTXEyT5++TnGF75vQ0E+RanniJebf3OES4CjHJzRVDUWww89PJLJNnnA2EwUKgJaLOWwQSJTB4Q== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from CH3PR12MB8659.namprd12.prod.outlook.com (2603:10b6:610:17c::13) by CH2PR12MB4184.namprd12.prod.outlook.com (2603:10b6:610:a7::9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8377.23; Wed, 29 Jan 2025 20:15:57 +0000 Received: from CH3PR12MB8659.namprd12.prod.outlook.com ([fe80::6eb6:7d37:7b4b:1732]) by CH3PR12MB8659.namprd12.prod.outlook.com ([fe80::6eb6:7d37:7b4b:1732%5]) with mapi id 15.20.8377.021; Wed, 29 Jan 2025 20:15:57 +0000 Date: Wed, 29 Jan 2025 16:15:56 -0400 From: Jason Gunthorpe To: Eric Auger Cc: Nicolin Chen , will@kernel.org, robin.murphy@arm.com, kevin.tian@intel.com, tglx@linutronix.de, maz@kernel.org, alex.williamson@redhat.com, joro@8bytes.org, shuah@kernel.org, reinette.chatre@intel.com, yebin10@huawei.com, apatel@ventanamicro.com, shivamurthy.shastri@linutronix.de, bhelgaas@google.com, anna-maria@linutronix.de, yury.norov@gmail.com, nipun.gupta@amd.com, iommu@lists.linux.dev, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org, patches@lists.linux.dev, jean-philippe@linaro.org, mdf@kernel.org, mshavit@google.com, shameerali.kolothum.thodi@huawei.com, smostafa@google.com, ddutile@redhat.com Subject: Re: [PATCH RFCv2 09/13] iommufd: Add IOMMU_OPTION_SW_MSI_START/SIZE ioctls Message-ID: <20250129201556.GK5556@nvidia.com> References: <0521187e-c511-4ab1-9ffa-be2be8eacd04@redhat.com> <20250129145800.GG5556@nvidia.com> <21ac88b0-fe93-4933-893c-7ffb09267e7b@redhat.com> <20250129173909.GI5556@nvidia.com> <6f630a23-e1b5-48de-81a6-43cbb1e6cabd@redhat.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <6f630a23-e1b5-48de-81a6-43cbb1e6cabd@redhat.com> X-ClientProxiedBy: BN1PR13CA0014.namprd13.prod.outlook.com (2603:10b6:408:e2::19) To CH3PR12MB8659.namprd12.prod.outlook.com (2603:10b6:610:17c::13) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CH3PR12MB8659:EE_|CH2PR12MB4184:EE_ X-MS-Office365-Filtering-Correlation-Id: f6d8ab8a-5291-4177-78bf-08dd40a1bdca X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|376014|366016|1800799024; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?E7VXlKODMRJHvK+hpS+cFYEbk++9gXySN3SquoyZKlDg4d7q1W/D3PwsbwGC?= =?us-ascii?Q?3ap+10rubMBhNAM62gvlaiJ6Tsr/l3eD7B6sN4qK1BDKM3yd0KZdrfJARbKi?= =?us-ascii?Q?CoENpMi+JV1drC4+MIqMPScXUIkypDr5/d5+a5vMS0NY6AhL7pAkuoVY+pk7?= =?us-ascii?Q?y9NR5B8A5whid4uyHVmWrw94M1gyy8hrez/Cj5YSNkAGAa1DIP+/zzYRhbHu?= =?us-ascii?Q?MKKdxFp40KOcfvraQAnEcgFiOjq9iYzhYWx/CGPozsm+RBwDyXUL6kvpbT46?= =?us-ascii?Q?PHez8M+PnwxLwg27puMrxKdZ7VFGkX1p45mgOYcfvYmBIc1XZmlT6/I6J918?= =?us-ascii?Q?8n/4FHdEUMr9iwmzKhrGjw1v7SO1T4gvWHXXBaXdnrlsr5WUq3JvE5FsXLro?= =?us-ascii?Q?Crst2dH8W4Bj/P6K/EQbUnhN+S4F1JkJH8At+JWd+RWEdTkPiLWofCu0ir0i?= =?us-ascii?Q?1eD4VN2SG0M2cLwQGtoTT38MW5VwqDFwhJZ7oTtgmvQq32eEDX7eFALN1kW8?= =?us-ascii?Q?c2Utx2n/Qb/1bNoZehST7+aoxrYCVcMfJIiVNpd7KkIogWDyX1ahXLabTd3c?= =?us-ascii?Q?cbzrxMWfHx83XrP2VIqAvYMB09s1cG7VngPmTy2lA8REXqtM8Kc9MnnojgLP?= =?us-ascii?Q?nzY3+wi5vHRVtlCDphQgV8qlbaKQFtszkNESgBNLdQ+6GNoJFAK1dmD73P5O?= =?us-ascii?Q?2Iq6titO0JuGKEhgF4wuTUfOX5wPbK0w8D/qrJnzCdlUd4QhugbssAFLcIZA?= =?us-ascii?Q?y5oZDV5+FBQLmlggqibTHIH8qGtJPFaD3La55YgC2/qn8I5ayY8kyOgsYuW6?= =?us-ascii?Q?uUuDFIjHbJWRVTtP9n25DvHL3VtyD4M9Vd5oWhGC3C+ideWmtjrxB6uaLQds?= =?us-ascii?Q?U8QhHrwToP8guUZPEbI2DPT7TF2ics9UYvd8wSdZj1WlDfIJkv9q4sMbD9B2?= =?us-ascii?Q?WZYfIC791yL9sWYSOgumxeGrCYDEuivMk7F5P5AFy4onRF8BzuxwwkR0vGAi?= =?us-ascii?Q?WilvwW3Z6Xtz5rN4HXH8zgyQ3YpP/MHnW1XnRo1G4qfJ6QOhfAk2tWk0KjY4?= =?us-ascii?Q?/XzpzQLkV5qWYWTPl1w+5ct4371ekn1z81fDw+bQWdf/dKghTJC62mRF2ibI?= =?us-ascii?Q?pSAs+4HiSMpwHprAJ3MRDP0TKRAZ098wE/TDZAPrJqZ7+OOC48+KfrByCPfS?= =?us-ascii?Q?2rbJghvjppN4Ey1mbA5j86v5nNMIdixIL3TiqqlGduRdkgqRqpLacA0eLM8a?= =?us-ascii?Q?mqSzHqmi9moHTSYZL/BkbliJgvLLmDXS5xnR4DTTrPApml8FsRauKGq1CCb3?= =?us-ascii?Q?Zi5fRRVbcuqnkBpAc6rU40IeQEmxkbJ2KPLKO/d0lW9cFbrkxsrYh2kgujzL?= =?us-ascii?Q?pTYY7x7MQXAHtjCXUeDnDqxf9tj3?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:CH3PR12MB8659.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(7416014)(376014)(366016)(1800799024);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?63mRtmSWUJnNsXAGNmbUNMQkiPKvEQn8VQZk6YCx2N1VqSRJIPUoGdigZfe1?= =?us-ascii?Q?MJu2XYyvqMXS9jBrm7hmbmOVfDd4hxiCpHnEch4OS4768Illy1lL/rcfrOTF?= =?us-ascii?Q?S6JV5imldCB9wFoRpdq+V3jOg33DhwnUYlbesIE9t/wMS5tOFmrCaQBF+XmN?= =?us-ascii?Q?B9IiqZJleWSRCloMEzPGBTB+nrRhIc7Fugokv+mfJ1nfMOKDfR3MDdMalCn4?= =?us-ascii?Q?PIXuISG2b9DvbuvFjWbTOhjudHwzqEHSUy2EOx3h+R6/AMvlQJbgJ4syMhQV?= =?us-ascii?Q?71dxCYcckrYN78kwk3zsQS69HXtBlCBxkZ8JHgVwee+m6b+BkMZoVhxAQFbk?= =?us-ascii?Q?pzfK8jzpp8N+Ix4rlS26eqzftkQ/u+6ihmtQfeTnuY0r63039DbNPj6nmk6X?= =?us-ascii?Q?DCF9JJH5ZJ19nOnu7ixxQQ7NJHwSvt3ReZHYTGem0DhpEyBP0clMsLdqW10a?= =?us-ascii?Q?g6RDSawX5wmMRWJ2b22ZoRWpCcN+EWBIlG8/GGumEbhxEStkuvQDtvrV0BTF?= =?us-ascii?Q?wpPiUTe3v7q3t+BHXtRUpBMcZ6qGV6/OBRqUbY7yO5xZuvPUxoBHZrAaGH0v?= =?us-ascii?Q?RzuZrQjMpCAMQushE4uaXeFDcKS5iGdCBDtmDBvstcHePAQET8mbb5MNYjp+?= =?us-ascii?Q?Swe8cN2mU+Hb9ZGZrSBGyYNGnosE8X0gzOJQKFTvrJwpALVo0ydv4RHV1GtB?= =?us-ascii?Q?oJtzJ+ifM58kJbpcjCzMf9CZCU4Qd5APFCoi9gh01woXvWOulJpuQMWvGkja?= =?us-ascii?Q?zTUdKx+zzGak0AbicGIWHSKxsOcd+8kIVdLM3whQ6E82XMD5CpRS+nJAm2ss?= =?us-ascii?Q?FV2aaLHDZFdwKxc+4OUIJFQkp2heuaN9i5T2JjormRED9K74jetAaxZzXI+s?= =?us-ascii?Q?J+oFn+oKWlS79QD+XGdTukTro/81GbNz8gmaveoyHhsPd3d629+6R9BnaE+C?= =?us-ascii?Q?yOQCurh0baI6PWj6xOvpQGhwNk9Zp2Z8b+7Ov4V66LIJEvp+bcp6dOhhPdxO?= =?us-ascii?Q?GBkt6YtMMNX5t6Y34mgoSxMQPWE6IQF9/KP3VMylxLDapHPLcCnQtSivixQZ?= =?us-ascii?Q?qQU6u/Xasmd7Vj3ptF6wcQgrgJzfJ+EULxn6DbaH9tEceQNocGjfl9NRb62H?= =?us-ascii?Q?+fLsoxPeD2zce2wnvRZ6188H/IV2qy0n692kGylZDhquvMl0EE/zfiAM1/a0?= =?us-ascii?Q?tAi8/OODNI6Hle7NXVbcxat2aqZovsZNG2sDnMh0S0tmLtHwN7Rl8VCMLL2z?= =?us-ascii?Q?V3CpIDb1/8McC3G3mI8OcbbTfLDgTe0Z6beVkboOsE5rtWVdU+pTugZs/zQs?= =?us-ascii?Q?Fp0piPi1zw+qxAWpCePIg+4k0ehyvM0C3mDJuns49/H6byroW8dInXbZqIiA?= =?us-ascii?Q?ndNqCr9yWtvkA/Htn4aqb+B5rVqeoTblvlgJDBvt1Q5QSNnqXnxyVG3YpYXc?= =?us-ascii?Q?uV/U/Z77h9OX6mpn7fcj0XI+0TPIry81bWCqbxymE0XEIxjSDB629e5EvQyQ?= =?us-ascii?Q?Gosa6ukyEFfUn/Wbr0WFMqaZfGvANjVOVphTq6aJhWfso6nxl8N8PIZZ8KGv?= =?us-ascii?Q?cthHPQ+6VUA7UtsXAlXy7B71Nvfqx7ba1sgKDQgr?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: f6d8ab8a-5291-4177-78bf-08dd40a1bdca X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 29 Jan 2025 20:15:57.6674 (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: j6SZYgv7HzHEn2NKEegL8PkdjwK0tvS2WMPalYTscPVc9U6UahVuMmmz2QvM/pzI X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH2PR12MB4184 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250129_121602_986333_8AC1CDDB X-CRM114-Status: GOOD ( 13.13 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Jan 29, 2025 at 06:49:22PM +0100, Eric Auger wrote: > > If it was overriden inside iommufd then the user told the kernel what > > range to use to override it. I don't need to go back and report back > > to userspace information that it already gave to the kernel.. > > Looks strange to me because info exposed in sysfs is wrong then. What if > someone else relies on this info, either at kernel level through the > get_resv_regions callback or from user space. Nothing else should call get_resv_regions() because VFIO is bound to the device and iommufd owns the domain. We expect some exclusivity here :) sysfs for sw_msi should be understood as reporting the driver recommendation, not anything to do with the current MSI operation of the device. Jason