diff --git a/hw/net/rtl8139.c b/hw/net/rtl8139.c
index 671c7e48c6f47a510c58da0baae9ac8ac9ca7381..3be24bbee74f18300bad90db2a2e2697d491583d 100644
--- a/hw/net/rtl8139.c
+++ b/hw/net/rtl8139.c
@@ -3132,38 +3132,6 @@ static uint32_t rtl8139_io_readl(void *opaque, uint8_t addr)
 
 /* */
 
-static void rtl8139_mmio_writeb(void *opaque, hwaddr addr, uint32_t val)
-{
-    rtl8139_io_writeb(opaque, addr & 0xFF, val);
-}
-
-static void rtl8139_mmio_writew(void *opaque, hwaddr addr, uint32_t val)
-{
-    rtl8139_io_writew(opaque, addr & 0xFF, val);
-}
-
-static void rtl8139_mmio_writel(void *opaque, hwaddr addr, uint32_t val)
-{
-    rtl8139_io_writel(opaque, addr & 0xFF, val);
-}
-
-static uint32_t rtl8139_mmio_readb(void *opaque, hwaddr addr)
-{
-    return rtl8139_io_readb(opaque, addr & 0xFF);
-}
-
-static uint32_t rtl8139_mmio_readw(void *opaque, hwaddr addr)
-{
-    uint32_t val = rtl8139_io_readw(opaque, addr & 0xFF);
-    return val;
-}
-
-static uint32_t rtl8139_mmio_readl(void *opaque, hwaddr addr)
-{
-    uint32_t val = rtl8139_io_readl(opaque, addr & 0xFF);
-    return val;
-}
-
 static int rtl8139_post_load(void *opaque, int version_id)
 {
     RTL8139State* s = opaque;
@@ -3344,22 +3312,6 @@ static const MemoryRegionOps rtl8139_io_ops = {
     .endianness = DEVICE_LITTLE_ENDIAN,
 };
 
-static const MemoryRegionOps rtl8139_mmio_ops = {
-    .old_mmio = {
-        .read = {
-            rtl8139_mmio_readb,
-            rtl8139_mmio_readw,
-            rtl8139_mmio_readl,
-        },
-        .write = {
-            rtl8139_mmio_writeb,
-            rtl8139_mmio_writew,
-            rtl8139_mmio_writel,
-        },
-    },
-    .endianness = DEVICE_LITTLE_ENDIAN,
-};
-
 static void rtl8139_timer(void *opaque)
 {
     RTL8139State *s = opaque;
@@ -3422,8 +3374,9 @@ static void pci_rtl8139_realize(PCIDevice *dev, Error **errp)
 
     memory_region_init_io(&s->bar_io, OBJECT(s), &rtl8139_io_ops, s,
                           "rtl8139", 0x100);
-    memory_region_init_io(&s->bar_mem, OBJECT(s), &rtl8139_mmio_ops, s,
-                          "rtl8139", 0x100);
+    memory_region_init_alias(&s->bar_mem, OBJECT(s), "rtl8139-mem", &s->bar_io,
+                             0, 0x100);
+
     pci_register_bar(dev, 0, PCI_BASE_ADDRESS_SPACE_IO, &s->bar_io);
     pci_register_bar(dev, 1, PCI_BASE_ADDRESS_SPACE_MEMORY, &s->bar_mem);