static void queue_comp_task(struct ehca_cq *__cq);
 
 static struct ehca_comp_pool* pool;
+#ifdef CONFIG_HOTPLUG_CPU
 static struct notifier_block comp_pool_callback_nb;
+#endif
 
 static inline void comp_event_callback(struct ehca_cq *cq)
 {
 
 }
 
+#ifdef CONFIG_HOTPLUG_CPU
 static int comp_pool_callback(struct notifier_block *nfb,
                              unsigned long action,
                              void *hcpu)
 
        return NOTIFY_OK;
 }
+#endif
 
 int ehca_create_comp_pool(void)
 {
                }
        }
 
+#ifdef CONFIG_HOTPLUG_CPU
        comp_pool_callback_nb.notifier_call = comp_pool_callback;
        comp_pool_callback_nb.priority =0;
        register_cpu_notifier(&comp_pool_callback_nb);
+#endif
 
        printk(KERN_INFO "eHCA scaling code enabled\n");
 
        if (!ehca_scaling_code)
                return;
 
+#ifdef CONFIG_HOTPLUG_CPU
        unregister_cpu_notifier(&comp_pool_callback_nb);
+#endif
 
        for (i = 0; i < NR_CPUS; i++) {
                if (cpu_online(i))