diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index e3cf8a2e629216208750bc96ed84285e7a2c0118..7c8ca351beae72b5a8595a24a8cd1a80de3be34c 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -838,16 +838,12 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
 			goto out;
 		}
 
-		if (max >= bus->busn_res.end) {
-			dev_warn(&dev->dev, "can't allocate child bus %02x from %pR\n",
-				 max, &bus->busn_res);
-			goto out;
-		}
-
 		/* Clear errors */
 		pci_write_config_word(dev, PCI_STATUS, 0xffff);
 
-		/* The bus will already exist if we are rescanning */
+		/* Prevent assigning a bus number that already exists.
+		 * This can happen when a bridge is hot-plugged, so in
+		 * this case we only re-scan this bus. */
 		child = pci_find_bus(pci_domain_nr(bus), max+1);
 		if (!child) {
 			child = pci_add_new_bus(bus, dev, max+1);