PCI/ACPI: fix wrong assumption in acpi_find_root_bridge_handle
Current acpi_find_root_bridge_handle() has a assumption that
pci_bus->self is NULL on the root pci bus. But it might not be true on
some platforms. Because of this wrong assumption, current
acpi_find_root_bridge_handle() might cause endless loop. We must check
pci_bus->parent instead.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h
index 3cee236..092e82e 100644
--- a/include/linux/pci-acpi.h
+++ b/include/linux/pci-acpi.h
@@ -13,12 +13,12 @@
#ifdef CONFIG_ACPI
static inline acpi_handle acpi_find_root_bridge_handle(struct pci_dev *pdev)
{
- /* Find root host bridge */
- while (pdev->bus->self)
- pdev = pdev->bus->self;
-
- return acpi_get_pci_rootbridge_handle(pci_domain_nr(pdev->bus),
- pdev->bus->number);
+ struct pci_bus *pbus = pdev->bus;
+ /* Find a PCI root bus */
+ while (pbus->parent)
+ pbus = pbus->parent;
+ return acpi_get_pci_rootbridge_handle(pci_domain_nr(pbus),
+ pbus->number);
}
static inline acpi_handle acpi_pci_get_bridge_handle(struct pci_bus *pbus)