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    "msgid": "<20260212191818.3625264-1-dcostantino@meta.com>",
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    "date": "2026-02-12T19:18:16",
    "name": "[0/2] PCI/DPC: Fix EDR recovery path issues",
    "submitter": {
        "id": 92636,
        "url": "http://patchwork.ozlabs.org/api/people/92636/?format=api",
        "name": "Danielle Costantino",
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            "date": "2026-02-12T19:18:16",
            "name": "PCI/DPC: Fix EDR recovery path issues",
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        "From": "Danielle Costantino <dcostantino@meta.com>",
        "To": "Bjorn Helgaas <bhelgaas@google.com>",
        "CC": "Keith Busch <kbusch@kernel.org>,\n        Kuppuswamy Sathyanarayanan\n\t<sathyanarayanan.kuppuswamy@linux.intel.com>,\n        Lukas Wunner <lukas@wunner.de>,\n        Mahesh J Salgaonkar <mahesh@linux.ibm.com>,\n        Oliver O'Halloran\n\t<oohall@gmail.com>, <linux-pci@vger.kernel.org>,\n        Danielle Costantino\n\t<dcostantino@meta.com>",
        "Subject": "[PATCH 0/2] PCI/DPC: Fix EDR recovery path issues",
        "Date": "Thu, 12 Feb 2026 11:18:16 -0800",
        "Message-ID": "<20260212191818.3625264-1-dcostantino@meta.com>",
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    "content": "Two fixes for the firmware-first EDR path in DPC error recovery.\n\nBoth were found investigating recurring DPC events on a platform using\nfirmware-first EDR, where each recovery left stale state in the DPC\nStatus register and cleared AER diagnostic data before driver callbacks\ncould inspect it.\n\nPatch 1 fixes DPC Interrupt Status (bit 3) never being cleared in the\nEDR path.  In native DPC, dpc_irq() clears it in the top-half, but\nEDR bypasses dpc_irq() entirely.  After this fix, dpc_reset_link()\nclears both Trigger Status and Interrupt Status together.\n\nPatch 2 moves pci_aer_raw_clear_status() from before pcie_do_recovery()\nto after it in edr_handle_event(), so AER registers remain readable\nthroughout the driver recovery callbacks.\n\nTested on a firmware-first EDR platform.  A natural DPC event\nconfirmed:\n  - DPC Status properly cleared: 0x2000 (clean) vs 0x2008 (stale, unpatched)\n  - AER data available during recovery (GHES captured aer_uncor_status:\n    0x00100010 throughout recovery window)\n  - Full recovery successful in ~2.3s with link re-establishment\n\nDanielle Costantino (2):\n  PCI/DPC: Clear Interrupt Status in dpc_reset_link()\n  PCI/EDR: Defer AER status clearing until after recovery\n\n drivers/pci/pcie/dpc.c | 10 +++++++++-\n drivers/pci/pcie/edr.c | 11 ++++++++++-\n 2 files changed, 19 insertions(+), 2 deletions(-)\n\n--\n2.47.3"
}