diff --git a/hw/vga-isa.c b/hw/vga-isa.c
index 0d199015d7..6b5c8ed970 100644
--- a/hw/vga-isa.c
+++ b/hw/vga-isa.c
@@ -49,6 +49,7 @@ static int vga_initfn(ISADevice *dev)
     MemoryRegion *vga_io_memory;
 
     vga_common_init(s, VGA_RAM_SIZE);
+    s->legacy_address_space = isa_address_space(dev);
     vga_io_memory = vga_init_io(s);
     memory_region_add_subregion_overlap(isa_address_space(dev),
                                         isa_mem_base + 0x000a0000,