Current acpi_get_hp_hw_control_from_firmware() has a assumption that pci_bus->self is NULL on a PCI root bus. But it might not be true on some platforms. Because of this wrong assumption, current acpi_get_hp_hw_control_from_firmware() might cause endless loop. We must check pci_bus->parent instead. Signed-off-by: Kenji Kaneshige <kaneshige.kenji@xxxxxxxxxxxxxx> --- drivers/pci/hotplug/acpi_pcihp.c | 34 ++++++++++++---------------------- 1 file changed, 12 insertions(+), 22 deletions(-) Index: linux-2.6.29-rc2/drivers/pci/hotplug/acpi_pcihp.c =================================================================== --- linux-2.6.29-rc2.orig/drivers/pci/hotplug/acpi_pcihp.c +++ linux-2.6.29-rc2/drivers/pci/hotplug/acpi_pcihp.c @@ -373,12 +373,10 @@ EXPORT_SYMBOL_GPL(acpi_get_hp_params_fro * * Attempt to take hotplug control from firmware. */ -int acpi_get_hp_hw_control_from_firmware(struct pci_dev *dev, u32 flags) +int acpi_get_hp_hw_control_from_firmware(struct pci_dev *pdev, u32 flags) { acpi_status status; acpi_handle chandle, handle; - struct pci_dev *pdev = dev; - struct pci_bus *parent; struct acpi_buffer string = { ACPI_ALLOCATE_BUFFER, NULL }; flags &= (OSC_PCI_EXPRESS_NATIVE_HP_CONTROL | @@ -410,26 +408,18 @@ int acpi_get_hp_hw_control_from_firmware string = (struct acpi_buffer){ ACPI_ALLOCATE_BUFFER, NULL }; } - pdev = dev; - handle = DEVICE_ACPI_HANDLE(&dev->dev); - while (!handle) { + handle = DEVICE_ACPI_HANDLE(&pdev->dev); + if (!handle) { /* * This hotplug controller was not listed in the ACPI name * space at all. Try to get acpi handle of parent pci bus. */ - if (!pdev || !pdev->bus->parent) - break; - parent = pdev->bus->parent; - dbg("Could not find %s in acpi namespace, trying parent\n", - pci_name(pdev)); - if (!parent->self) - /* Parent must be a host bridge */ - handle = acpi_get_pci_rootbridge_handle( - pci_domain_nr(parent), - parent->number); - else - handle = DEVICE_ACPI_HANDLE(&(parent->self->dev)); - pdev = parent->self; + struct pci_bus *pbus; + for (pbus = pdev->bus; pbus; pbus = pbus->parent) { + handle = acpi_pci_get_bridge_handle(pbus); + if (handle) + break; + } } while (handle) { @@ -448,13 +438,13 @@ int acpi_get_hp_hw_control_from_firmware } dbg("Cannot get control of hotplug hardware for pci %s\n", - pci_name(dev)); + pci_name(pdev)); kfree(string.pointer); return -ENODEV; got_one: - dbg("Gained control for hotplug HW for pci %s (%s)\n", pci_name(dev), - (char *)string.pointer); + dbg("Gained control for hotplug HW for pci %s (%s)\n", + pci_name(pdev), (char *)string.pointer); kfree(string.pointer); return 0; } -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html