diff --git a/libsel4utils/src/irq_server/irq_server.c b/libsel4utils/src/irq_server/irq_server.c
index 602b815..f44d296 100644
--- a/libsel4utils/src/irq_server/irq_server.c
+++ b/libsel4utils/src/irq_server/irq_server.c
@@ -351,7 +351,8 @@
 
     /* Set max_ntfn_ids to equal the number of IRQs. We can calculate the ntfn IDs we need,
      * but this is really complex, and leads to code that is hard to maintain. */
-    error = sel4platsupport_new_irq_ops(&(new->irq_ops), vka, simple, num_irqs, num_irqs, malloc_ops);
+    irq_interface_config_t irq_config = { .max_irq_ids = num_irqs, .max_ntfn_ids = num_irqs } ;
+    error = sel4platsupport_new_irq_ops(&(new->irq_ops), vka, simple, irq_config, malloc_ops);
     if (error) {
         ZF_LOGE("Failed to initialise supporting backend for IRQ server");
         return NULL;