Zhangfei Gao c8ba3f8aff PCI: Run quirk_huawei_pcie_sva() before arm_smmu_probe_device()
quirk_huawei_pcie_sva() sets properties needed by arm_smmu_probe_device(),
but bcb81ac6ae ("iommu: Get DT/ACPI parsing into the proper probe path")
changed the iommu_probe_device() flow so arm_smmu_probe_device() is now
invoked before the quirk, leading to failures like this:

  reg-dummy reg-dummy: late IOMMU probe at driver bind, something fishy here!
  WARNING: CPU: 0 PID: 1 at drivers/iommu/iommu.c:449 __iommu_probe_device+0x140/0x570
  RIP: 0010:__iommu_probe_device+0x140/0x570

The SR-IOV enumeration ordering changes like this:

  pci_iov_add_virtfn
    pci_device_add
      pci_fixup_device(pci_fixup_header)      <--
      device_add
        bus_notify
          iommu_bus_notifier
  +         iommu_probe_device
  +           arm_smmu_probe_device
    pci_bus_add_device
      pci_fixup_device(pci_fixup_final)       <--
      device_attach
        driver_probe_device
          really_probe
            pci_dma_configure
              acpi_dma_configure_id
  -             iommu_probe_device
  -               arm_smmu_probe_device

The non-SR-IOV case is similar in that pci_device_add() is called from
pci_scan_single_device() in the generic enumeration path and
pci_bus_add_device() is called later, after all host bridges have been
enumerated.

Declare quirk_huawei_pcie_sva() as a header fixup to ensure that it happens
before arm_smmu_probe_device().

Fixes: bcb81ac6ae ("iommu: Get DT/ACPI parsing into the proper probe path")
Reported-by: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com>
Closes: https://lore.kernel.org/all/SJ1PR11MB61295DE21A1184AEE0786E25B9D22@SJ1PR11MB6129.namprd11.prod.outlook.com/
Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
[bhelgaas: commit log, add failure info and reporter]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20250317011352.5806-1-zhangfei.gao@linaro.org
2025-04-11 12:53:21 -05:00
2025-04-06 10:00:04 -07:00
2025-04-06 13:11:33 -07:00

Linux kernel
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