diff --git a/hw/pci-host/grackle.c b/hw/pci-host/grackle.c
index 4991ec4..d70c519 100644
--- a/hw/pci-host/grackle.c
+++ b/hw/pci-host/grackle.c
@@ -105,9 +105,9 @@ static int pci_grackle_init_device(SysBusDevice *dev)
     phb = PCI_HOST_BRIDGE(dev);
 
     memory_region_init_io(&phb->conf_mem, OBJECT(dev), &pci_host_conf_le_ops,
-                          dev, "pci-conf-idx", 0x1000);
+                          dev, "pci-conf-idx", 4);
     memory_region_init_io(&phb->data_mem, OBJECT(dev), &pci_host_data_le_ops,
-                          dev, "pci-data-idx", 0x1000);
+                          dev, "pci-data-idx", 4);
     sysbus_init_mmio(dev, &phb->conf_mem);
     sysbus_init_mmio(dev, &phb->data_mem);
 
diff --git a/hw/pci-host/uninorth.c b/hw/pci-host/uninorth.c
index 91530cd..2238646 100644
--- a/hw/pci-host/uninorth.c
+++ b/hw/pci-host/uninorth.c
@@ -153,7 +153,7 @@ static int pci_unin_main_init_device(SysBusDevice *dev)
     h = PCI_HOST_BRIDGE(dev);
 
     memory_region_init_io(&h->conf_mem, OBJECT(h), &pci_host_conf_le_ops,
-                          dev, "pci-conf-idx", 0x1000);
+                          dev, "pci-conf-idx", 4);
     memory_region_init_io(&h->data_mem, OBJECT(h), &unin_data_ops, dev,
                           "pci-conf-data", 0x1000);
     sysbus_init_mmio(dev, &h->conf_mem);
@@ -171,7 +171,7 @@ static int pci_u3_agp_init_device(SysBusDevice *dev)
     h = PCI_HOST_BRIDGE(dev);
 
     memory_region_init_io(&h->conf_mem, OBJECT(h), &pci_host_conf_le_ops,
-                          dev, "pci-conf-idx", 0x1000);
+                          dev, "pci-conf-idx", 4);
     memory_region_init_io(&h->data_mem, OBJECT(h), &unin_data_ops, dev,
                           "pci-conf-data", 0x1000);
     sysbus_init_mmio(dev, &h->conf_mem);
@@ -188,7 +188,7 @@ static int pci_unin_agp_init_device(SysBusDevice *dev)
     h = PCI_HOST_BRIDGE(dev);
 
     memory_region_init_io(&h->conf_mem, OBJECT(h), &pci_host_conf_le_ops,
-                          dev, "pci-conf-idx", 0x1000);
+                          dev, "pci-conf-idx", 4);
     memory_region_init_io(&h->data_mem, OBJECT(h), &pci_host_data_le_ops,
                           dev, "pci-conf-data", 0x1000);
     sysbus_init_mmio(dev, &h->conf_mem);
@@ -204,7 +204,7 @@ static int pci_unin_internal_init_device(SysBusDevice *dev)
     h = PCI_HOST_BRIDGE(dev);
 
     memory_region_init_io(&h->conf_mem, OBJECT(h), &pci_host_conf_le_ops,
-                          dev, "pci-conf-idx", 0x1000);
+                          dev, "pci-conf-idx", 4);
     memory_region_init_io(&h->data_mem, OBJECT(h), &pci_host_data_le_ops,
                           dev, "pci-conf-data", 0x1000);
     sysbus_init_mmio(dev, &h->conf_mem);