diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c
index a2297db8081322a6ca51f2b6d32fadf385e1236c..07aa722bb12cd61a6a3a8767b2efe1dd826e6952 100644
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -255,6 +255,13 @@ static int pciehp_probe(struct pcie_device *dev)
 	else if (pciehp_acpi_slot_detection_check(dev->port))
 		goto err_out_none;
 
+	if (!dev->port->subordinate) {
+		/* Can happen if we run out of bus numbers during probe */
+		dev_err(&dev->device,
+			"Hotplug bridge without secondary bus, ignoring\n");
+		goto err_out_none;
+	}
+
 	ctrl = pcie_init(dev);
 	if (!ctrl) {
 		dev_err(&dev->device, "Controller initialization failed\n");