}
 #endif /* MAX_HWIFS > 1 */
 
+static inline int hwif_to_node(ide_hwif_t *hwif)
+{
+       if (hwif->pci_dev)
+               return pcibus_to_node(hwif->pci_dev->bus);
+       else
+               /* Add ways to determine the node of other busses here */
+               return -1;
+}
+
 /*
  * init request queue
  */
         *      do not.
         */
 
-       q = blk_init_queue_node(do_ide_request, &ide_lock,
-                               pcibus_to_node(drive->hwif->pci_dev->bus));
+       q = blk_init_queue_node(do_ide_request, &ide_lock, hwif_to_node(hwif));
        if (!q)
                return 1;
 
 
        BUG_ON(in_interrupt());
        BUG_ON(irqs_disabled());        
+       BUG_ON(hwif == NULL);
+
        down(&ide_cfg_sem);
        hwif->hwgroup = NULL;
 #if MAX_HWIFS > 1
                spin_unlock_irq(&ide_lock);
        } else {
                hwgroup = kmalloc_node(sizeof(ide_hwgroup_t), GFP_KERNEL,
-                       pcibus_to_node(hwif->drives[0].hwif->pci_dev->bus));
+                                       hwif_to_node(hwif->drives[0].hwif));
                if (!hwgroup)
                        goto out_up;