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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 BL4PR12MB9478.namprd12.prod.outlook.com (2603:10b6:208:58e::9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.569.9; Fri, 30 Oct 2026 01:23:28 +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 15.21.0569.008; Fri, 30 Oct 2026 01:23:28 +0000 Message-ID: <096fa1b9-b28f-447a-a7f9-e473056b4bf4@nvidia.com> Date: Thu, 29 Oct 2026 18:23:23 -0700 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v15 10/16] PCI/CXL: Add CXL Device Reset sequencing To: Li Ming , 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 Cc: 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: <20261011021422.3428136-1-smadhavan@nvidia.com> <20261011021422.3428136-11-smadhavan@nvidia.com> <37c6f2bc-53b3-4260-aa27-04f89c45e950@zohomail.com> Content-Language: en-US From: Srirangan Madhavan In-Reply-To: <37c6f2bc-53b3-4260-aa27-04f89c45e950@zohomail.com> Content-Type: text/plain; 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>> +     if (rc) >> +             return pcibios_err_to_errno(rc); >> +     if (PCI_POSSIBLE_ERROR(ctrl2)) >> +             return -ENODEV; > > I think this PCI_POSSIBLE_ERROR() checking is not needed, in > pci_bus_read_config_word() marco, if bus->ops->read() returns a error, > then the function will use PCI_SET_ERROR_RESPONSE() then returning the > errno. That means that we can always get an error as return value of > pci_read_config_word() while ctrl2 is an error response. I kept the PCI_POSSIBLE_ERROR() checks in v16 because I believe configuration read can return success with an all-ones value. For example, pci_generic_config_read() returns success after readw(), even if the value read is 0xffff. Please let me know if that assumption is incorrect. -- Regards, Srirangan