[PATCH 3/8] PCI hotplug: fix wrong assumption in acpi_get_hp_params_from_firmware

Kenji Kaneshige
2009-01-28T11:51:26Z

Current acpi_get_hp_params_from_firmware() has a assumption that
pci_bus->self is NULL on the root pci bus. But it might not true on
some platforms. Because of this wrong assumption, current
acpi_get_hp_params_from_firmware() might cause endless loop. We must
check pci_bus->parent instead.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>

---
drivers/pci/hotplug/acpi_pcihp.c | 17 ++++++-----------
1 file changed, 6 insertions(+), 11 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
@@ -333,19 +333,14 @@ acpi_status acpi_get_hp_params_from_firm
{
acpi_status status = AE_NOT_FOUND;
acpi_handle handle, phandle;
- struct pci_bus *pbus = bus;
- struct pci_dev *pdev;
+ struct pci_bus *pbus;

- do {
- pdev = pbus->self;
- if (!pdev) {
- handle = acpi_get_pci_rootbridge_handle(
- pci_domain_nr(pbus), pbus->number);
+ handle = NULL;
+ for (pbus = bus; pbus; pbus = pbus->parent) {
+ handle = acpi_pci_get_bridge_handle(pbus);
+ if (handle)
break;
- }
- handle = DEVICE_ACPI_HANDLE(&(pdev->dev));
- pbus = pbus->parent;
- } while (!handle);
+ }

/*
* _HPP settings apply to all child buses, until another _HPP is