From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=pass header.oldest-pass=0 smtp.remote-ip=52.101.43.3 ARC-Seal: i=2; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=pass; t=1793897426; b=134VzoeLsdfezGu8cfdAk7+436YIRrI2t/x0keTYXqz9Hma9yHQ2mhcbbkyTxP9FnRd9 WkjHpkBOsLnFmu2Wd9epq8wBaBAp5mtrV6iN4S3wFXejHWs7AoP4kTKb5cbrvrKSdLO17 iLM40eLT4uEuFcdzV6a0gzUjpu/K7a+rTvujHxM7YxHo/zgo6W5JNv1VscSXndnF7b9a7 aNsqRsz6dRYXCEVxPnYhf2CaU2LYC2XLUdDN7B8WClh66zU19daunm127nh6Irf5A0Iin yjA4xPL5Tc4Ovtbn38Rl2nwvRvF9aWvX+4sGjSlHbotJWUkfw8XQFgCZFPPPjKxBEhA== ARC-Message-Signature: i=2; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793897426; h=DMARC-Filter:DKIM-Signature:Received:Received:Message-ID:Date: User-Agent:Subject:To:Cc:References:Content-Language:From:In-Reply-To: Content-Type:Content-Transfer-Encoding:X-ClientProxiedBy:MIME-Version: X-MS-PublicTrafficType:X-MS-TrafficTypeDiagnostic: X-MS-Office365-Filtering-Correlation-Id:X-MS-Exchange-SenderADCheck: X-MS-Exchange-AntiSpam-Relay:X-Microsoft-Antispam: X-Microsoft-Antispam-Message-Info:X-Forefront-Antispam-Report: X-MS-Exchange-AntiSpam-MessageData-ChunkCount: X-MS-Exchange-AntiSpam-MessageData-0:X-OriginatorOrg: X-MS-Exchange-CrossTenant-Network-Message-Id: X-MS-Exchange-CrossTenant-AuthSource:X-MS-Exchange-CrossTenant-AuthAs: X-MS-Exchange-CrossTenant-OriginalArrivalTime: X-MS-Exchange-CrossTenant-FromEntityHeader: X-MS-Exchange-CrossTenant-Id:X-MS-Exchange-CrossTenant-MailboxType: X-MS-Exchange-CrossTenant-UserPrincipalName: X-MS-Exchange-Transport-CrossTenantHeadersStamped; bh=u/2eRG2TbTCqLMP3KMdemToQDZbMrOfiyYj00In6B/M=; b=m3A6WXF6/lBC8E3d/PpqeETVPojKbubF96pr+kgnrLXgkE8WZwYXoPc8qLyNot2L0QTl 1nTtv91rPvMh7I0yBt/1hvBDS1wIXRb51q10vAN7+HeDnNHCy7nncwBCpsvgkLCQuq7B9 IuyuPJ5bsoUEzgNbu6jufeWO66UMI5bWUYmst7uADQI5ulaLt8IackJ5jJMskB3rNDt/K kOVl7wbOTpfaO1Szhu0E1cIWO6SdtrJnto7z7upkHx5c723HNWldA6Y4hBfFtwfqBxVoY cb6XM+joR6v8Yo5ie6EvMGSrRQAQoyH2A6xSOspHBNnznVe8wiHmel4kP6zyM2RQQZw== ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass header.from=nvidia.com; spf=fail smtp.mailfrom=nvidia.com; dkim=pass header.d=Nvidia.com header.i=@Nvidia.com header.a=rsa-sha256 header.s=selector2 header.b="l/4tDfIh"; arc=pass header.oldest-pass=0 smtp.remote-ip=52.101.43.3 Received: from SJ2PR03CU001.outbound.protection.outlook.com (mail-westusazon11012003.outbound.protection.outlook.com [52.101.43.3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (secp384r1) server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E819E606A333; Thu, 5 Nov 2026 16:50:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org E819E606A333 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, unprotected) header.d=Nvidia.com header.i=@Nvidia.com header.a=rsa-sha256 header.s=selector2 header.b=l/4tDfIh ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=TvJeIcD2ib+/l06HbDLF8vdQCk+QGWCNIKKFYHnnMYf6StSmieEccymj0NXXIwDdlJ3UIYV4abl7XUsaHhDT+vsNX6plz9uxJmdQzXsgfdfsVelN9G4b+uCsYNls7B6T4pUcdcTiYEMGZwg1qnRTv+KbpLQsjcwrRAzl+3tFs0281VS5QAV8FHys3eNtwbKXVMFJ26q9Q7mzdNnA+pHsogLgmnVGL9h4O2nB2VdYu7f+Pwgz7a1030F2sM+O2yf7nt1CqB9Mgafb8f+U6nl6HW+f60qHEdP6tYG1CRSk2m7PdSOd05oxKN7/01olLfNzEaVDXzu8DS6JKPvjux0kZg== 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=u/2eRG2TbTCqLMP3KMdemToQDZbMrOfiyYj00In6B/M=; b=yrbdwVlv+ZfbBDATApB2NW/bNG7caOiI3uu4hUmRC1famMu5dL3j8qMQbW/MTDdsIVV7UGYtG4wU/9zNLrQXU9c0aVaXUwXFoYJMfpRWOMHLrgH5H6j12yTGxSQFfXQUkwfMo1lGzQ5Bk/ZF3P0q+Gr38jWWax/xDplz+Pt1eQnjQNZbb2M+TwRLpI5zsu/VYQhd2x3DAQrMhmHzzWfMoxpTRPyRqh+6XsMG6NIhscrIzJPzMU1g8S2H13m/V0Er5M3ZUHAzDIv3UpuzduDZI94AhmjVXEJowAklBQHyh13a2lGYvVx3K6nX1rYuj8TUtLX9Cy7Qz9XwjhFvpaZWEA== 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=u/2eRG2TbTCqLMP3KMdemToQDZbMrOfiyYj00In6B/M=; b=l/4tDfIh4TqdDSYuLUXAUzNQk6MCo8TrRmMTULpm25OIQVpKvBxHj3yg0Y3+3hwhI26I8ff8PDEXqXko4KETjHr9aA2DHENwWaljSg/urb7+CPRZJganGm43OR5g/bGUFrIiP/3cmLx6Ftbq6vqDEuXHzxDo6P/XSJW1R0nWTnPTNEI3ixCr/2ao+9sDsmWBMdbE8dFSr9LHHbFjFz7OMCd2kX8madVbmqgglNlBZ6KF3ndfUTdxPSN7GBJzDzuLvseLjLZARLoydtD7x0EFnhYkJJ/pPVIZTCn/6+Z7kkzNjH1CHLYK/cHO4n0JQNTS5H4lHqtKNcH5usNdgd4xrQ== Authentication-Results: mx.microsoft.com 1; dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from LY0PR12MB727857.namprd12.prod.outlook.com (2603:10b6:408:3ba::5) by SJ2PR12MB7868.namprd12.prod.outlook.com (2603:10b6:a03:4cd::11) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.592.10; Thu, 5 Nov 2026 16:50:19 +0000 Received: from LY0PR12MB727857.namprd12.prod.outlook.com ([fe80::843e:82cd:41ca:f522]) by LY0PR12MB727857.namprd12.prod.outlook.com ([fe80::843e:82cd:41ca:f522%5]) with mapi id 15.21.0592.009; Thu, 5 Nov 2026 16:50:19 +0000 Message-ID: <8f16600d-2ff7-4235-85bc-22f1cc929167@nvidia.com> Date: Thu, 5 Nov 2026 08:50:14 -0800 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v16 14/18] PCI/CXL: Reject reset with unsafe function scope To: Joshua Machauer Cc: Alison Schofield , Bjorn Helgaas , Dave Jiang , Davidlohr Bueso , Ira Weiny , Jonathan Cameron , Vishal Verma , linux-cxl@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Li Ming , Alex Williamson , vsethi@nvidia.com, alwilliamson@nvidia.com, Sai Yashwanth Reddy Kancherla , Vishal Aslot , Manish Honap , Jiandi An , Richard Cheng , linux-tegra@vger.kernel.org References: <20261029145703.2185231-1-smadhavan@nvidia.com> <20261029145703.2185231-15-smadhavan@nvidia.com> <20261105143611.31563-1-machaujo@amazon.de> Content-Language: en-US From: Srirangan Madhavan In-Reply-To: <20261105143611.31563-1-machaujo@amazon.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: MW4PR03CA0210.namprd03.prod.outlook.com (2603:10b6:303:b8::35) To LY0PR12MB727857.namprd12.prod.outlook.com (2603:10b6:408:3ba::5) X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: LY0PR12MB727857:EE_|SJ2PR12MB7868:EE_ X-MS-Office365-Filtering-Correlation-Id: 76dcc546-85cb-4365-2fdf-08df3b5cdfe2 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|23010399003|366016|376014|1800799024|7416014|261022105027099003|261021121427099003|261009223027099003|261026140227099003|261028144727099003|261102123227099003|10067099003|4143699003|11063799006|56012099006|18002099003|6133799003|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:LY0PR12MB727857.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(23010399003)(366016)(376014)(1800799024)(7416014)(261022105027099003)(261021121427099003)(261009223027099003)(261026140227099003)(261028144727099003)(261102123227099003)(10067099003)(4143699003)(11063799006)(56012099006)(18002099003)(6133799003)(22082099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?S0RxV0t4YktpSDkvRGhjSFpodlA3emNhb20zc1NNcGVFRi9XL1BLYWxXc1FZ?= =?utf-8?B?SURWV1dIRTVJUUxYSmtLN0FXd1NFanBnVUMrTnprbEwvaGNPYXEzbm5DUEpo?= =?utf-8?B?U2d0VHA5dHMzRkxMOCtmMDhSeEljdi9lTHNVVDE4U1lZWS9qdHd0YzQ5VnhY?= =?utf-8?B?di9xQlo1bXlTMkpoWlFXeHB4ZEpuMnVNeEtYcGVKQ0ZSa2JJT0hvZXprTUpG?= =?utf-8?B?N1FOOVZlRmpPTkxiSENwMExjaTFZRE5HL3FLblhwc0JCcStoemRydGtFU0Qy?= =?utf-8?B?N2lmM0pwcGk3NTFXREswN2ZuTktuWmRhaitPZjNaenY1OStJWUVQZWloaFNh?= =?utf-8?B?YlFJeE5nL2Z2czJIZG9CSzdnN2F5bURxZHUzeHJGUHZXTUZZMXVhQmZPYW96?= =?utf-8?B?aTQ5Qm9zMzdzczcwUXJEZTczWjNzZzVXUDVyUldmZzdPeVQ0K0orcGZpcjg2?= =?utf-8?B?czV3NzFnTm9UZDdabGxDUGVYenF0Z0owbThqZkxHbGZVM285QlZVbXBLQlVs?= =?utf-8?B?cGhLYnJNaTJOdWdlRFdSb3pOdVQyZTg3NHBla3VRNTJMVmZwSDdsS3JQdkw0?= =?utf-8?B?YVlzenRuM2lTb3lBdUZXRk1JeGlwMWU2Nk85WkZ3VDRwd2Fhc3QyT2RBZnho?= =?utf-8?B?Y0RGc0ZJdkNYdG91RGhodlNJYS9Cd2NsWjU2eEo0V3h1QlNFeHBueU9TMW0z?= =?utf-8?B?a3U3Umh6eFhJMTVlb2kycDBTZGlWTFVYbnkvL3FyNFJJMjBKNUVRaTRHUXhW?= =?utf-8?B?anhRcUhLR3JwVjEvZVRETDYzVnlMVTErajg0ODBxOFRzb3o5bHFZdnVXT1pN?= =?utf-8?B?OU85Nm1Ya3A0RWVXSG1vRmpxQ0s1N1dNWUFDcHY3dWV1QndGK1VFMDVFOHVy?= =?utf-8?B?T2MvbUJ4WitHZ1BXWFM2YVowVzVCOFRzM0o4Mm45Yk5OVlhuSTYwZTFWSXBR?= =?utf-8?B?U1FBeGZuYkQ3bStoejU2VUY5YlQ5b0FjcXlYYmRrdGZzZXRoQ05sRVRTVDdz?= =?utf-8?B?K1FNRWdZMjBYeVJoaWZSMndCeGNqUjBndlhMZXdxTVZqUHU0Vk14UWxtbXJL?= =?utf-8?B?UlVoUFlnK252WUtZaTB4T2J6Vmg1eUVMc3IwWGtqSlpWQlFlNTNUekFaYUZM?= =?utf-8?B?OHVGYnp0ME9Ha2dycVkxQVZpQ0xqVzJjK2gvcnNYSjMxQkZFdFNMRklHSUM0?= =?utf-8?B?d0RGUVBDRGdidXJXQS9La2JNd2tSODQ3NnRHblNEYnpHQVpqbE9qQ2hFOUdu?= =?utf-8?B?M2p1ZnVDSTNKOGhoWFlRM2g3TU5EVlNEbld6NDJtbGFYZXMxcVR5UVFOUzg4?= =?utf-8?B?Ykp3aXQrYWYxcUlrTmFMU3hsUERCbnJwUFNnZ0tnVjJaZDBjcjFyOUxTWGVJ?= =?utf-8?B?NDVxZzVNSW83Zkw2eDNBTkxyeE9sbnFzT3BiYVFkUlIxSi93elA3L2VaUW9t?= =?utf-8?B?UjRzNnM1M1Y0aElldkk3YnVkeU5PU0xNRkhGS2JhYUlYN3dqcnhxT2xaV2U3?= =?utf-8?B?QW50RHFVOFcwem5ZL3R1VklIa0FKTzk1TnBLQ1JXU1BodDRUeVZVMEQ1cnF6?= =?utf-8?B?UUxpYXR4NTVPbFdpQk4yVzZwSzJiMnFaOFRoTXlzeWJPNEpWTmQvR25uMjVK?= =?utf-8?B?VGhNRzNlU1FkUEpYajZsWnpmNXY4cFhWR0c3OFhXd1AwdklZTTdMNjBSdEdK?= =?utf-8?B?Uk9KU3JEdjE2Y3RhMzBVVnhjNkQ4bm51T2gvSTJvTnFCWCsxYjZxc2g2dUM5?= =?utf-8?B?dWVERFQ5TDA1bVRnZjVONVdLYlhmdWFMQnE0dVV6UlJHZzkwQ3FJenlxdGVt?= =?utf-8?B?S1pmbzlsSTNHSXdVdXY1N1JKazNORWgza29HWkdhbjJTcHkvWnNVb1V0Rkta?= =?utf-8?B?dkdDRzBiaC9oNHRQQm13ejUwZ3lhUWpqUzdKeXZHTGw5T085QUZVbC9wT0N5?= =?utf-8?B?SWVvTUd5cEpVNEtYMzY0ZTNITnJ1TG1uN0oxd3dvMmdUNXJQdnlDK04wSi9I?= =?utf-8?B?T2N5aDJKajBwQ1lGdVVqWExlWkpLTTBucDE1M2crV3pvVThyZUVPUEIya0xm?= =?utf-8?B?eWxRSFJSeFp0L3VORlRXd1pxd05XUCtFNU16SjdWemZaYUU1WDV0cVpJdUQw?= =?utf-8?B?Um5vS2JJcXZOMjVTVVFRQjlmSGxydWprWTgySDBJZTVtM3d4djROdm5iNWRB?= =?utf-8?B?REVXV2JXVWxXdmFkQ0thMGFkR3VLSm9iVTlJeXo2U2tiRjFuSmZyQWRlejMy?= =?utf-8?B?a2ROSGptR3IxcGtrSEl6Qm5jVjBsMk1uVmhORmhxeEhYYjBIMi83TDhYcjl6?= =?utf-8?B?S3lvNmNDVVdDd254TFlmZlU0eE5CQllzaGpxVXBOaHY3dzRGN3FQUT09?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 76dcc546-85cb-4365-2fdf-08df3b5cdfe2 X-MS-Exchange-CrossTenant-AuthSource: LY0PR12MB727857.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 05 Nov 2026 16:50:18.9942 (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: xfbAlIi4S/GDC/VGbL3vbpmzMWQhjUfpR08krO4T3obxcBtKFZhpro9wqwdIPPy9hjPNjmPr1hmcHVtXkQKEAA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ2PR12MB7868 On 11/5/26 6:36 AM, Joshua Machauer wrote: > External email: Use caution opening links or attachments > > > On Thu, Oct 29, 2026 at 02:56:59PM +0000, Srirangan Madhavan wrote: >> @@ -515,6 +515,9 @@ int cxl_reset_function(struct pci_dev *pdev, bool probe) >> !(ctrl & PCI_DVSEC_CXL_MEM_ENABLE)) >> return -ENOTTY; >> >> + if (pdev->is_virtfn || pdev->multifunction || pci_num_vf(pdev)) >> + return -ENOTTY; >> + >> if (probe) >> return 0; > > [...] > >> @@ -5026,6 +5026,9 @@ static int cxl_reset_bus_function(struct pci_dev *dev, bool probe) >> if (!dvsec) >> return -ENOTTY; >> >> + if (dev->is_virtfn || dev->multifunction || pci_num_vf(dev)) >> + return -ENOTTY; >> + >> if (probe) >> return 0; > > Could both checks go at the top of their functions, before the DVSEC > lookups? None of the three conditions depends on what the lookups > find. > > pci_init_reset_methods() probes every reset method for every device > that is added, and enabling SR-IOV adds the VFs one after another. > Where the checks are now, each VF probe walks the extended > capabilities twice before it returns -ENOTTY: cxl_reset walks the > VF's own list for the CXL Device DVSEC, and cxl_bus walks the > upstream bridge's list for the CXL Port DVSEC. All VFs of a PF share > that bridge, so its walk repeats once per VF with the same result. > > With the checks first, a VF returns -ENOTTY without a config read, > and the result for every device stays the same. > > Thanks, > Joshua Hi Joshua, Thanks, that makes sense. In v17 both checks run at the top of cxl_reset_function() and cxl_reset_bus_function(), before the DVSEC lookups. -- Regards, Srirangan