diff --git a/hw/isa-bus.c b/hw/isa-bus.c
index 27655436a0f423eb6d618ece3e6128121c1d8b54..1cb497f5cad125418063ecc305f6d2b31700bf27 100644
--- a/hw/isa-bus.c
+++ b/hw/isa-bus.c
@@ -20,6 +20,7 @@
 #include "monitor.h"
 #include "sysbus.h"
 #include "isa.h"
+#include "exec-memory.h"
 
 struct ISABus {
     BusState qbus;
@@ -202,4 +203,9 @@ static char *isabus_get_fw_dev_path(DeviceState *dev)
     return strdup(path);
 }
 
+MemoryRegion *isa_address_space(ISADevice *dev)
+{
+    return get_system_memory();
+}
+
 device_init(isabus_register_devices)
diff --git a/hw/isa.h b/hw/isa.h
index f1f21812d6e9943b1b0ad904022a4c00b1474522..f344699722fc4668a4d1e5b519cf421777edced8 100644
--- a/hw/isa.h
+++ b/hw/isa.h
@@ -32,6 +32,7 @@ void isa_init_irq(ISADevice *dev, qemu_irq *p, int isairq);
 void isa_init_ioport(ISADevice *dev, uint16_t ioport);
 void isa_init_ioport_range(ISADevice *dev, uint16_t start, uint16_t length);
 void isa_qdev_register(ISADeviceInfo *info);
+MemoryRegion *isa_address_space(ISADevice *dev);
 ISADevice *isa_create(const char *name);
 ISADevice *isa_try_create(const char *name);
 ISADevice *isa_create_simple(const char *name);