diff --git a/hw/display/cirrus_vga.c b/hw/display/cirrus_vga.c
index 3a53f20392..ec923c8c4b 100644
--- a/hw/display/cirrus_vga.c
+++ b/hw/display/cirrus_vga.c
@@ -2907,7 +2907,7 @@ static void cirrus_init_common(CirrusVGAState *s, Object *owner,
                                             bank, 1);
     }
     memory_region_add_subregion_overlap(system_memory,
-                                        isa_mem_base + 0x000a0000,
+                                        0x000a0000,
                                         &s->low_mem_container,
                                         1);
     memory_region_set_coalescing(&s->low_mem);
diff --git a/hw/display/vga-isa.c b/hw/display/vga-isa.c
index 2b480bd44d..7f3c98941b 100644
--- a/hw/display/vga-isa.c
+++ b/hw/display/vga-isa.c
@@ -64,7 +64,7 @@ static void vga_isa_realizefn(DeviceState *dev, Error **errp)
         isa_register_portio_list(isadev, 0x1ce, vbe_ports, s, "vbe");
     }
     memory_region_add_subregion_overlap(isa_address_space(isadev),
-                                        isa_mem_base + 0x000a0000,
+                                        0x000a0000,
                                         vga_io_memory, 1);
     memory_region_set_coalescing(vga_io_memory);
     s->con = graphic_console_init(DEVICE(dev), 0, s->hw_ops, s);
diff --git a/hw/display/vga.c b/hw/display/vga.c
index 9c62fbf488..c8c49abc6e 100644
--- a/hw/display/vga.c
+++ b/hw/display/vga.c
@@ -177,7 +177,6 @@ static void vga_update_memory_access(VGACommonState *s)
             size = 0x8000;
             break;
         }
-        base += isa_mem_base;
         memory_region_init_alias(&s->chain4_alias, memory_region_owner(&s->vram),
                                  "vga.chain4", &s->vram, offset, size);
         memory_region_add_subregion_overlap(s->legacy_address_space, base,
@@ -2218,7 +2217,7 @@ void vga_init(VGACommonState *s, Object *obj, MemoryRegion *address_space,
 
     vga_io_memory = vga_init_io(s, obj, &vga_ports, &vbe_ports);
     memory_region_add_subregion_overlap(address_space,
-                                        isa_mem_base + 0x000a0000,
+                                        0x000a0000,
                                         vga_io_memory,
                                         1);
     memory_region_set_coalescing(vga_io_memory);
diff --git a/hw/isa/isa-bus.c b/hw/isa/isa-bus.c
index fd6a3a19e7..825aa627df 100644
--- a/hw/isa/isa-bus.c
+++ b/hw/isa/isa-bus.c
@@ -23,7 +23,6 @@
 #include "hw/isa/isa.h"
 
 static ISABus *isabus;
-hwaddr isa_mem_base = 0;
 
 static void isabus_dev_print(Monitor *mon, DeviceState *dev, int indent);
 static char *isabus_get_fw_dev_path(DeviceState *dev);
diff --git a/include/hw/isa/isa.h b/include/hw/isa/isa.h
index c6218224d5..cf7bd343c7 100644
--- a/include/hw/isa/isa.h
+++ b/include/hw/isa/isa.h
@@ -99,8 +99,6 @@ static inline ISABus *isa_bus_from_device(ISADevice *d)
     return ISA_BUS(qdev_get_parent_bus(DEVICE(d)));
 }
 
-extern hwaddr isa_mem_base;
-
 /* dma.c */
 int DMA_get_channel_mode (int nchan);
 int DMA_read_memory (int nchan, void *buf, int pos, int size);