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 31E4CCDB47E for ; Wed, 18 Oct 2023 12:39:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230310AbjJRMjy (ORCPT ); Wed, 18 Oct 2023 08:39:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45832 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231209AbjJRMAe (ORCPT ); Wed, 18 Oct 2023 08:00:34 -0400 Received: from NAM11-CO1-obe.outbound.protection.outlook.com (mail-co1nam11on2065.outbound.protection.outlook.com [40.107.220.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 336C4FE for ; Wed, 18 Oct 2023 05:00:33 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=N5fB8TmUFpBX1N8fd7Rx6MSdwLNK8/3TDJL6O9yer/0RiJnEiclyBikK27k4nAUCisynvrBcxqs+i01RDm5KCdO+DwrfPK3pIQ9N/VosRAHPnASKsi2BRSZVeE8GUckSGEWrYbABhvycMiYTTay2xfF1chUtLB3T1hSlU5MgeYhI1SQHM0PTVcCsw69vVwHaIg6OOOhEKuSI/NeTathyTWBIlTVXYdNXwV9UK2eQW7uglFo6xyIwbPzZ4Gfoq4k/f56EjjAlEyuJkz37AGBqmiicUdq3Vw1ZcGjW9IHSTPb+k1bdfSXnYir3r+S3mz3MsuJrPnvsSh6L1UTOFV8adQ== 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=Jinj9AH+FXwN7FpP7Piy7NaZeyEX7b9xiGeMSfWx7dg=; b=Apkbj106pWlHY5NAEviT/ZCKGNwnuEdaQBaFiJiLZzpCSmFfv+cRRNb2DJSOfDPfla5053eYTVJtJEPBFf2KrWvYjVqS9SQBK6vsdIwugXpE+TwpgQ6bKke89iCK63bY5ZpnK/SNQmSpOMqbXZoF+68CUEB9MtWKV7zbswJQbmDvv5XAxecm9vE7/LWou7dZ7k1GgYXtw6VORc+oJJ8lFpkDWBEaeIva2nb8znXRg+LUpnyWXg9QNH2nU3R17AoR2aP74MtJ9vgAOu2aWyoIk4S2zl50u+Q7eYeAK9MLo/9MhJx8j9Jh3CsfWOTxjo3Ib/ONMRo5FfLdSKKuhnWyLw== 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=Jinj9AH+FXwN7FpP7Piy7NaZeyEX7b9xiGeMSfWx7dg=; b=LKQYvuiJ3R33Yo2Y8MqHGffkCN1P9n1W2g3B2Y6zOfrWe2Ow6xRv8qyeYFdYhXoKx5ghfEe3wTWaTsWUwug/2gwydk6e8+fC5aOMKKte7hF8myx7VHl6AHBiJXWQzKY1SsnoNCSB279gFBVwxYANbR35GGOBYK/HKHsR9ZCu4406lLSyDVUDMGOOoZNzmLa6+BHolSNcC/C316o+5F5ihYkAAoMqR1dYztrCeP92HEsIautjwKCo4Pgq7r4r3+fWJ53sAqRXvWxA/NcjEfGIoiEhLR5s1yHHoc5FJHSqG6p0mZ9moHXS/ggQnXKXOxQybBraATBcSUOPHfK4Eg4SKw== 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 PH7PR12MB6738.namprd12.prod.outlook.com (2603:10b6:510:1a9::16) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6886.34; Wed, 18 Oct 2023 12:00:29 +0000 Received: from LV2PR12MB5869.namprd12.prod.outlook.com ([fe80::3f66:c2b6:59eb:78c2]) by LV2PR12MB5869.namprd12.prod.outlook.com ([fe80::3f66:c2b6:59eb:78c2%6]) with mapi id 15.20.6886.034; Wed, 18 Oct 2023 12:00:29 +0000 Date: Wed, 18 Oct 2023 09:00:25 -0300 From: Jason Gunthorpe To: Greg Kroah-Hartman Cc: Saeed Mahameed , Arnd Bergmann , linux-kernel@vger.kernel.org, Leon Romanovsky , Jiri Pirko , Saeed Mahameed Subject: Re: [PATCH 0/5] mlx5 ConnectX diagnostic misc driver Message-ID: <20231018120025.GQ3952@nvidia.com> References: <20231018081941.475277-1-saeed@kernel.org> <2023101858-underwire-donated-3ae9@gregkh> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2023101858-underwire-donated-3ae9@gregkh> X-ClientProxiedBy: BYAPR03CA0032.namprd03.prod.outlook.com (2603:10b6:a02:a8::45) To LV2PR12MB5869.namprd12.prod.outlook.com (2603:10b6:408:176::16) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: LV2PR12MB5869:EE_|PH7PR12MB6738:EE_ X-MS-Office365-Filtering-Correlation-Id: d207c14f-8bfc-4365-8282-08dbcfd1d26a X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; 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:LV2PR12MB5869.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230031)(346002)(136003)(396003)(39860400002)(376002)(366004)(230922051799003)(1800799009)(186009)(451199024)(64100799003)(6506007)(1076003)(107886003)(2616005)(38100700002)(26005)(6916009)(316002)(66556008)(66946007)(54906003)(66476007)(6486002)(6512007)(83380400001)(478600001)(6666004)(4326008)(5660300002)(8936002)(41300700001)(8676002)(2906002)(33656002)(36756003)(86362001)(21314003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Psdtj9J9wTmHmnLRBBMnr3S91AaLdoF9kJrRHAozUBoZ3DKYfshaMvp+nZyw?= =?us-ascii?Q?emzxIuuI0+sWwa894qVJ2KGsGn4twYAbyBIQECSwOY1RoZl5sYoZ2VY6fQbH?= =?us-ascii?Q?rL/VcHIp147h0xPJFB4funxP6En+BcFeoJQP7CIRQ4aoiTj35hLdjzaR68Xp?= =?us-ascii?Q?frl+V23xGkmRmZZk6lF8NJoiNIebWsuVKGS2vLRJtA6FCmoB1j9kz0sG5y/V?= =?us-ascii?Q?CNfwYxIq2lNBAI0/hxGkA2dTvZ8ndncyzrt0BmJDT39bDovanHzdA42O4qfX?= =?us-ascii?Q?kUoBQMRoHf+bLJonRPPiDWA6lZjFRVupH4LrcP3xend6pH06EStd1LDTRxjI?= =?us-ascii?Q?kysXYIeFgumwusgmkA1tX8fxkHyJfIhoPaqss++u1lpEqzbzeHC6Oji49xb3?= =?us-ascii?Q?cvR3B19DhQRxgo275+fLou8jknLKW/5olAPeyKz4mKt2O79C2s8jFtzvsJiU?= =?us-ascii?Q?jsEcOXzAOtBAgF5IQ5l/1MzKn9zebwAuDqbGsKno7M2HQN3mmog9nkW7S+Ol?= =?us-ascii?Q?+Hb7k0WS13YtS8hKZXC8sCwU1xN+wgNfyYtTTRaKW7IrdkfDexqbUCs898CC?= =?us-ascii?Q?yccHNdRNHEyGqhyg0XsI0V+ClbCLwbSnhkkcs1VJl7kV+ARC/Oyaejf6vBLT?= =?us-ascii?Q?p5f6mrbsSobmBk8REk4UftQnBUg7aZb3Uxu237mLME/aYmYql5vmmesEtKfY?= =?us-ascii?Q?bRknybyjARBZ8ymQ2C+H/g+KUjWlhySb13PyhUV7RLONMUllQfWF1tgj23SN?= =?us-ascii?Q?JXL+FhQnRePKUzbh5A9ZyepWIMYB3wn72VLZ0qXz6Fi77Lqj3K3rYsVFZlpD?= =?us-ascii?Q?tHEe14M+PfUc8BNf93dsx4/w61tUy/N7hvwlhkq/knrL5JvaLBf7+o6ylAz3?= =?us-ascii?Q?T/JyZMVUP4jjX/3LJMvr0ikMj+tC2sbJw7aW3OPlzLYVBFQCBzRuhsiMSzjc?= =?us-ascii?Q?yjz8QaRrnCzNrQXlA4ryD+Haq2Rn/2kM4jN1izwphSxcbZnv6694gpcAXI9l?= =?us-ascii?Q?h5Or9UaER1cw8wCbx9RHqftmrIf9NJcE8CiiCFPSvCwQqJar4SS76jB31mtZ?= =?us-ascii?Q?79QgAyr4I+0h1KJhbwfLclKRQZcYm4ZCvRidyfQK8Kqkrl7PgaQBXMXTFdX5?= =?us-ascii?Q?sjmOO9KWXrSagEqgGrArLzicZAXOQl80lHBxKbYDuFtrPq9IX1GMMNi7ceqE?= =?us-ascii?Q?SwGg7bBC2zUMOrJOdspq7I3bPX2TZRc7lc7Hez/UaBa+tvAbDep9a18XcSvz?= =?us-ascii?Q?AQZV5bxp/hVqmCbMVIr5QWvW3TQ9vpvtZwS2vG3Jairjs6oM669Yx/C5otY4?= =?us-ascii?Q?6783WmbaR9uGpzOqHVHoQigrnDtnZ5B4Z2eJDgw41l8u0UC56Dkia0gi29lH?= =?us-ascii?Q?0ynkdhX17bI71oA1GViv1Ym3811Qrh8Ay1oiCvsGBZJtsRWpXydvhXnTWbs1?= =?us-ascii?Q?g44WbI7QgE99gouWJJPDwgJbDwIkbGKBXzfCiWNsJ11rMuzwCYwkxw9TWvOF?= =?us-ascii?Q?dXE6buktguBiMx46d8CouDA5qQPjOFMt4+o0ExJEf1IyBc7KO1FKXVkP1vzP?= =?us-ascii?Q?JbAGDco5qFUba+lH8HXl4/S5IImMtMGg+t/p6Xso?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: d207c14f-8bfc-4365-8282-08dbcfd1d26a X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Oct 2023 12:00:28.9985 (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: OfHV8XuS/Fg70YbeQsPRJVSh+W+myxsOLQTLdF5GToXWIFgdeF+dfi6ON/mCAL9a X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB6738 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 18, 2023 at 10:31:23AM +0200, Greg Kroah-Hartman wrote: > On Wed, Oct 18, 2023 at 01:19:36AM -0700, Saeed Mahameed wrote: > > Historically a userspace program was used that accessed the PCI register > > and config space directly through /sys/bus/pci/.../XXX and could operate > > these debugging interfaces in parallel with the running driver. > > This approach is incompatible with secure boot and kernel lockdown so this > > driver provides a secure and restricted interface to that. > > Why not just write a UIO driver for this hardware then? The old mechanism relied on direct config space and sometimes mmio access to the PCI device. We did a security analysis and concluded that approach could not provide the required security for what our customers want from the secure boot and lockdown modes. We cannot allow a lockdown userspace direct access to those device registers. So, it was redesigned to be RPC driven instead of having direct HW access. The RPCs allow the device to provide the required level of security. This new misc driver does not expose any HW registers or interrupts to userspace, so it does not seem like a fit for UIO. Jason