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dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from BL0PR12MB2370.namprd12.prod.outlook.com (2603:10b6:207:47::27) by CH3PR12MB8457.namprd12.prod.outlook.com (2603:10b6:610:154::21) 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 09:55:05 +0000 Received: from BL0PR12MB2370.namprd12.prod.outlook.com ([fe80::86cf:c3ec:2cf5:74c8]) by BL0PR12MB2370.namprd12.prod.outlook.com ([fe80::86cf:c3ec:2cf5:74c8%5]) with mapi id 15.21.0569.008; Fri, 30 Oct 2026 09:55:05 +0000 Date: Fri, 30 Oct 2026 17:54:58 +0800 From: Richard Cheng To: jic23@kernel.org, dave@stgolabs.net, dave.jiang@intel.com, alison.schofield@intel.com, vishal.l.verma@intel.com, iweiny@kernel.org Cc: ming.li@zohomail.com, kaihengf@nvidia.com, kobak@nvidia.com, newtonl@nvidia.com, kristinc@nvidia.com, mochs@nvidia.com, linux-cxl@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/4] PCI/CXL: Guard reset recovery against inaccessible devices Message-ID: References: <20260929020405.9724-1-icheng@nvidia.com> Content-Type: text/plain; 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I would really appreciate any review feedback on it while you're available, thanks ! Best regards, Richard Cheng. > During FLR testing, PCI configuration reads returned all ones. The > kernel could mistake this for reset completion and proceed with MSI-X > restoration. The resulting MMIO access triggered DPC containment. > > This series addresses four issues: > > 1. Reject all-ones responses in pci_dev_wait(). Use Command-register > polling for VFs, whose Vendor ID legitimately reads as all ones. > > 2. Return -ETIMEDOUT when readiness polling expires, preventing fallback > to another reset method. > > 3. Check configuration accessibility before restoring PCI state, while > preserving driver reset callbacks. > > 4. Skip CXL decoder MMIO accesses when configuration is inaccessible > or memory decoding is disabled. > > > Best regards, > Richard Cheng. > > Richard Cheng (4): > PCI: Reject all-ones responses in pci_dev_wait() > PCI: Return -ETIMEOUT when reset readiness polling expires > PCI: Skip state restoration when configuration is inaccessible > cxl/pci: Guard decoder accesses after reset > > drivers/cxl/pci.c | 6 ++++++ > drivers/pci/pci.c | 16 +++++++++------- > 2 files changed, 15 insertions(+), 7 deletions(-) > > > base-commit: 9eb6419022d81aac6d1d9ead0e1865b451153da5 > -- > 2.43.0 >