1 files changed, 6 insertions, 1 deletions

diff --git a/arch/ia64/pci/pci.c b/arch/ia64/pci/pci.c
index e282c348dcde..53d0a8ee35d7 100644
--- a/arch/ia64/pci/pci.c
+++ b/arch/ia64/pci/pci.c
@@ -362,7 +362,12 @@ pci_acpi_scan_root(struct acpi_device *device, int domain, int bus)
         info.name = name;
         acpi_walk_resources(device->handle, METHOD_NAME__CRS, add_window,
                         &info);
-
+        /*
+         * See arch/x86/pci/acpi.c.
+         * The desired pci bus might already be scanned in a quirk. We
+         * should handle the case here, but it appears that IA64 hasn't
+         * such quirk. So we just ignore the case now.
+         */
         pbus = pci_scan_bus_parented(NULL, bus, &pci_root_ops, controller);
         if (pbus)
                 pcibios_setup_root_windows(pbus, controller);