Some PCI root bridges don't have a corresponding ACPI device. This can be the case on some old platforms. Don't call acpi_ioapic_add() on these bridges because they can't support ioapic hotplug.
v2: Per Boris's review, removed the unnecessary local var; refined comment Signed-off-by: Rui Wang <[email protected]> Reviewed-by: Borislav Petkov <[email protected]> --- drivers/pci/setup-bus.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index ec538d3..8b4e231 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -1855,7 +1855,10 @@ void __init pci_assign_unassigned_resources(void) list_for_each_entry(root_bus, &pci_root_buses, node) { pci_assign_unassigned_root_bus_resources(root_bus); - acpi_ioapic_add(ACPI_HANDLE(root_bus->bridge)); + + /* make sure the root bridge has a companion ACPI device */ + if (ACPI_HANDLE(root_bus->bridge)) + acpi_ioapic_add(ACPI_HANDLE(root_bus->bridge)); } } -- 1.8.3.1
