diff --git a/hw/core/sysbus.c b/hw/core/sysbus.c
index f4e760d6eb..414e2a1921 100644
--- a/hw/core/sysbus.c
+++ b/hw/core/sysbus.c
@@ -242,11 +242,6 @@ void sysbus_add_io(SysBusDevice *dev, hwaddr addr,
     memory_region_add_subregion(get_system_io(), addr, mem);
 }
 
-void sysbus_del_io(SysBusDevice *dev, MemoryRegion *mem)
-{
-    memory_region_del_subregion(get_system_io(), mem);
-}
-
 MemoryRegion *sysbus_address_space(SysBusDevice *dev)
 {
     return get_system_memory();
diff --git a/include/hw/sysbus.h b/include/hw/sysbus.h
index f5aaa05ee3..0bb91a8824 100644
--- a/include/hw/sysbus.h
+++ b/include/hw/sysbus.h
@@ -71,7 +71,6 @@ void sysbus_mmio_map_overlap(SysBusDevice *dev, int n, hwaddr addr,
                              int priority);
 void sysbus_add_io(SysBusDevice *dev, hwaddr addr,
                    MemoryRegion *mem);
-void sysbus_del_io(SysBusDevice *dev, MemoryRegion *mem);
 MemoryRegion *sysbus_address_space(SysBusDevice *dev);
 
 /* Legacy helper function for creating devices.  */