diff --git a/hw/i2c/bitbang_i2c.c b/hw/i2c/bitbang_i2c.c
index f550ba4..5f8b972 100644
--- a/hw/i2c/bitbang_i2c.c
+++ b/hw/i2c/bitbang_i2c.c
@@ -209,7 +209,7 @@ static int gpio_i2c_init(SysBusDevice *dev)
     GPIOI2CState *s = FROM_SYSBUS(GPIOI2CState, dev);
     i2c_bus *bus;
 
-    memory_region_init(&s->dummy_iomem, NULL, "gpio_i2c", 0);
+    memory_region_init(&s->dummy_iomem, OBJECT(s), "gpio_i2c", 0);
     sysbus_init_mmio(dev, &s->dummy_iomem);
 
     bus = i2c_init_bus(&dev->qdev, "i2c");
diff --git a/hw/i2c/exynos4210_i2c.c b/hw/i2c/exynos4210_i2c.c
index bc6eb34..52bffa5 100644
--- a/hw/i2c/exynos4210_i2c.c
+++ b/hw/i2c/exynos4210_i2c.c
@@ -301,8 +301,8 @@ static int exynos4210_i2c_realize(SysBusDevice *dev)
 {
     Exynos4210I2CState *s = EXYNOS4_I2C(dev);
 
-    memory_region_init_io(&s->iomem, NULL, &exynos4210_i2c_ops, s, TYPE_EXYNOS4_I2C,
-                          EXYNOS4_I2C_MEM_SIZE);
+    memory_region_init_io(&s->iomem, OBJECT(s), &exynos4210_i2c_ops, s,
+                          TYPE_EXYNOS4_I2C, EXYNOS4_I2C_MEM_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq);
     s->bus = i2c_init_bus(&dev->qdev, "i2c");
diff --git a/hw/i2c/omap_i2c.c b/hw/i2c/omap_i2c.c
index 1a8b39c..f0eb448 100644
--- a/hw/i2c/omap_i2c.c
+++ b/hw/i2c/omap_i2c.c
@@ -448,7 +448,7 @@ static int omap_i2c_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->irq);
     sysbus_init_irq(dev, &s->drq[0]);
     sysbus_init_irq(dev, &s->drq[1]);
-    memory_region_init_io(&s->iomem, NULL, &omap_i2c_ops, s, "omap.i2c",
+    memory_region_init_io(&s->iomem, OBJECT(s), &omap_i2c_ops, s, "omap.i2c",
                           (s->revision < OMAP2_INTR_REV) ? 0x800 : 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     s->bus = i2c_init_bus(&dev->qdev, NULL);
diff --git a/hw/i2c/pm_smbus.c b/hw/i2c/pm_smbus.c
index f425ad8..6df0fa9 100644
--- a/hw/i2c/pm_smbus.c
+++ b/hw/i2c/pm_smbus.c
@@ -181,5 +181,6 @@ static const MemoryRegionOps pm_smbus_ops = {
 void pm_smbus_init(DeviceState *parent, PMSMBus *smb)
 {
     smb->smbus = i2c_init_bus(parent, "i2c");
-    memory_region_init_io(&smb->io, NULL, &pm_smbus_ops, smb, "pm-smbus", 64);
+    memory_region_init_io(&smb->io, OBJECT(parent), &pm_smbus_ops, smb,
+                          "pm-smbus", 64);
 }
diff --git a/hw/i2c/versatile_i2c.c b/hw/i2c/versatile_i2c.c
index a239963..204dd3d 100644
--- a/hw/i2c/versatile_i2c.c
+++ b/hw/i2c/versatile_i2c.c
@@ -79,7 +79,7 @@ static int versatile_i2c_init(SysBusDevice *dev)
 
     bus = i2c_init_bus(&dev->qdev, "i2c");
     s->bitbang = bitbang_i2c_init(bus);
-    memory_region_init_io(&s->iomem, NULL, &versatile_i2c_ops, s,
+    memory_region_init_io(&s->iomem, OBJECT(s), &versatile_i2c_ops, s,
                           "versatile_i2c", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     return 0;
diff --git a/hw/i386/kvm/pci-assign.c b/hw/i386/kvm/pci-assign.c
index f1a5554..8e2c530 100644
--- a/hw/i386/kvm/pci-assign.c
+++ b/hw/i386/kvm/pci-assign.c
@@ -298,8 +298,8 @@ static void assigned_dev_iomem_setup(PCIDevice *pci_dev, int region_num,
     PCIRegion *real_region = &r_dev->real_device.regions[region_num];
 
     if (e_size > 0) {
-        memory_region_init(&region->container, NULL, "assigned-dev-container",
-                           e_size);
+        memory_region_init(&region->container, OBJECT(pci_dev),
+                           "assigned-dev-container", e_size);
         memory_region_add_subregion(&region->container, 0, &region->real_iomem);
 
         /* deal with MSI-X MMIO page */
@@ -329,9 +329,10 @@ static void assigned_dev_ioport_setup(PCIDevice *pci_dev, int region_num,
     AssignedDevRegion *region = &r_dev->v_addrs[region_num];
 
     region->e_size = size;
-    memory_region_init(&region->container, NULL, "assigned-dev-container", size);
-    memory_region_init_io(&region->real_iomem, NULL, &assigned_dev_ioport_ops,
-                          r_dev->v_addrs + region_num,
+    memory_region_init(&region->container, OBJECT(pci_dev),
+                       "assigned-dev-container", size);
+    memory_region_init_io(&region->real_iomem, OBJECT(pci_dev),
+                          &assigned_dev_ioport_ops, r_dev->v_addrs + region_num,
                           "assigned-dev-iomem", size);
     memory_region_add_subregion(&region->container, 0, &region->real_iomem);
 }
@@ -478,8 +479,9 @@ static int assigned_dev_register_regions(PCIRegion *io_regions,
                              "4K.  You might experience some performance hit "
                              "due to that.",
                              i, cur_region->base_addr, cur_region->size);
-                memory_region_init_io(&pci_dev->v_addrs[i].real_iomem, NULL,
-                                      &slow_bar_ops, &pci_dev->v_addrs[i],
+                memory_region_init_io(&pci_dev->v_addrs[i].real_iomem,
+                                      OBJECT(pci_dev), &slow_bar_ops,
+                                      &pci_dev->v_addrs[i],
                                       "assigned-dev-slow-bar",
                                       cur_region->size);
             } else {
@@ -487,9 +489,9 @@ static int assigned_dev_register_regions(PCIRegion *io_regions,
                 char name[32];
                 snprintf(name, sizeof(name), "%s.bar%d",
                          object_get_typename(OBJECT(pci_dev)), i);
-                memory_region_init_ram_ptr(&pci_dev->v_addrs[i].real_iomem, NULL,
-                                           name, cur_region->size,
-                                           virtbase);
+                memory_region_init_ram_ptr(&pci_dev->v_addrs[i].real_iomem,
+                                           OBJECT(pci_dev), name,
+                                           cur_region->size, virtbase);
                 vmstate_register_ram(&pci_dev->v_addrs[i].real_iomem,
                                      &pci_dev->dev.qdev);
             }
@@ -1650,8 +1652,8 @@ static int assigned_dev_register_msix_mmio(AssignedDevice *dev)
 
     assigned_dev_msix_reset(dev);
 
-    memory_region_init_io(&dev->mmio, NULL, &assigned_dev_msix_mmio_ops, dev,
-                          "assigned-dev-msix", MSIX_PAGE_SIZE);
+    memory_region_init_io(&dev->mmio, OBJECT(dev), &assigned_dev_msix_mmio_ops,
+                          dev, "assigned-dev-msix", MSIX_PAGE_SIZE);
     return 0;
 }
 
@@ -1916,7 +1918,7 @@ static void assigned_dev_load_option_rom(AssignedDevice *dev)
 
     snprintf(name, sizeof(name), "%s.rom",
             object_get_typename(OBJECT(dev)));
-    memory_region_init_ram(&dev->dev.rom, NULL, name, st.st_size);
+    memory_region_init_ram(&dev->dev.rom, OBJECT(dev), name, st.st_size);
     vmstate_register_ram(&dev->dev.rom, &dev->dev.qdev);
     ptr = memory_region_get_ram_ptr(&dev->dev.rom);
     memset(ptr, 0xff, st.st_size);
diff --git a/hw/i386/kvmvapic.c b/hw/i386/kvmvapic.c
index 21b5912..9850a85 100644
--- a/hw/i386/kvmvapic.c
+++ b/hw/i386/kvmvapic.c
@@ -601,8 +601,8 @@ static void vapic_map_rom_writable(VAPICROMState *s)
     rom_paddr &= TARGET_PAGE_MASK;
     rom_size = TARGET_PAGE_ALIGN(rom_size);
 
-    memory_region_init_alias(&s->rom, NULL, "kvmvapic-rom", section.mr, rom_paddr,
-                             rom_size);
+    memory_region_init_alias(&s->rom, OBJECT(s), "kvmvapic-rom", section.mr,
+                             rom_paddr, rom_size);
     memory_region_add_subregion_overlap(as, rom_paddr, &s->rom, 1000);
     s->rom_mapped_writable = true;
     memory_region_unref(section.mr);
@@ -703,7 +703,7 @@ static int vapic_init(SysBusDevice *dev)
 {
     VAPICROMState *s = VAPIC(dev);
 
-    memory_region_init_io(&s->io, NULL, &vapic_ops, s, "kvmvapic", 2);
+    memory_region_init_io(&s->io, OBJECT(s), &vapic_ops, s, "kvmvapic", 2);
     sysbus_add_io(dev, VAPIC_IO_PORT, &s->io);
     sysbus_init_ioports(dev, VAPIC_IO_PORT, 2);
 
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 4345187..e7ad931 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -525,7 +525,7 @@ static void port92_initfn(Object *obj)
 {
     Port92State *s = PORT92(obj);
 
-    memory_region_init_io(&s->io, NULL, &port92_ops, s, "port92", 1);
+    memory_region_init_io(&s->io, OBJECT(s), &port92_ops, s, "port92", 1);
 
     s->outport = 0;
 }
diff --git a/hw/ide/ahci.c b/hw/ide/ahci.c
index e18e1b1..bae484a 100644
--- a/hw/ide/ahci.c
+++ b/hw/ide/ahci.c
@@ -1156,8 +1156,10 @@ void ahci_init(AHCIState *s, DeviceState *qdev, AddressSpace *as, int ports)
     s->dev = g_malloc0(sizeof(AHCIDevice) * ports);
     ahci_reg_init(s);
     /* XXX BAR size should be 1k, but that breaks, so bump it to 4k for now */
-    memory_region_init_io(&s->mem, NULL, &ahci_mem_ops, s, "ahci", AHCI_MEM_BAR_SIZE);
-    memory_region_init_io(&s->idp, NULL, &ahci_idp_ops, s, "ahci-idp", 32);
+    memory_region_init_io(&s->mem, OBJECT(qdev), &ahci_mem_ops, s,
+                          "ahci", AHCI_MEM_BAR_SIZE);
+    memory_region_init_io(&s->idp, OBJECT(qdev), &ahci_idp_ops, s,
+                          "ahci-idp", 32);
 
     irqs = qemu_allocate_irqs(ahci_irq_set, s, s->ports);
 
diff --git a/hw/ide/cmd646.c b/hw/ide/cmd646.c
index a695dfb..33be386 100644
--- a/hw/ide/cmd646.c
+++ b/hw/ide/cmd646.c
@@ -117,8 +117,10 @@ static void setup_cmd646_bar(PCIIDEState *d, int bus_num)
 
     bar->bus = bus;
     bar->pci_dev = d;
-    memory_region_init_io(&bar->cmd, NULL, &cmd646_cmd_ops, bar, "cmd646-cmd", 4);
-    memory_region_init_io(&bar->data, NULL, &cmd646_data_ops, bar, "cmd646-data", 8);
+    memory_region_init_io(&bar->cmd, OBJECT(d), &cmd646_cmd_ops, bar,
+                          "cmd646-cmd", 4);
+    memory_region_init_io(&bar->data, OBJECT(d), &cmd646_data_ops, bar,
+                          "cmd646-data", 8);
 }
 
 static uint64_t bmdma_read(void *opaque, hwaddr addr,
@@ -203,13 +205,14 @@ static void bmdma_setup_bar(PCIIDEState *d)
     BMDMAState *bm;
     int i;
 
-    memory_region_init(&d->bmdma_bar, NULL, "cmd646-bmdma", 16);
+    memory_region_init(&d->bmdma_bar, OBJECT(d), "cmd646-bmdma", 16);
     for(i = 0;i < 2; i++) {
         bm = &d->bmdma[i];
-        memory_region_init_io(&bm->extra_io, NULL, &cmd646_bmdma_ops, bm,
+        memory_region_init_io(&bm->extra_io, OBJECT(d), &cmd646_bmdma_ops, bm,
                               "cmd646-bmdma-bus", 4);
         memory_region_add_subregion(&d->bmdma_bar, i * 8, &bm->extra_io);
-        memory_region_init_io(&bm->addr_ioport, NULL, &bmdma_addr_ioport_ops, bm,
+        memory_region_init_io(&bm->addr_ioport, OBJECT(d),
+                              &bmdma_addr_ioport_ops, bm,
                               "cmd646-bmdma-ioport", 4);
         memory_region_add_subregion(&d->bmdma_bar, i * 8 + 4, &bm->addr_ioport);
     }
diff --git a/hw/ide/macio.c b/hw/ide/macio.c
index 0c14009..4798202 100644
--- a/hw/ide/macio.c
+++ b/hw/ide/macio.c
@@ -335,7 +335,7 @@ static void macio_ide_initfn(Object *obj)
     MACIOIDEState *s = MACIO_IDE(obj);
 
     ide_bus_new(&s->bus, DEVICE(obj), 0, 2);
-    memory_region_init_io(&s->mem, NULL, &pmac_ide_ops, s, "pmac-ide", 0x1000);
+    memory_region_init_io(&s->mem, obj, &pmac_ide_ops, s, "pmac-ide", 0x1000);
     sysbus_init_mmio(d, &s->mem);
     sysbus_init_irq(d, &s->irq);
     sysbus_init_irq(d, &s->dma_irq);
diff --git a/hw/ide/mmio.c b/hw/ide/mmio.c
index 8ae57d6..d251ff9 100644
--- a/hw/ide/mmio.c
+++ b/hw/ide/mmio.c
@@ -124,9 +124,9 @@ static void mmio_ide_realizefn(DeviceState *dev, Error **errp)
 
     ide_init2(&s->bus, s->irq);
 
-    memory_region_init_io(&s->iomem1, NULL, &mmio_ide_ops, s,
+    memory_region_init_io(&s->iomem1, OBJECT(s), &mmio_ide_ops, s,
                           "ide-mmio.1", 16 << s->shift);
-    memory_region_init_io(&s->iomem2, NULL, &mmio_ide_cs_ops, s,
+    memory_region_init_io(&s->iomem2, OBJECT(s), &mmio_ide_cs_ops, s,
                           "ide-mmio.2", 2 << s->shift);
     sysbus_init_mmio(d, &s->iomem1);
     sysbus_init_mmio(d, &s->iomem2);
diff --git a/hw/ide/piix.c b/hw/ide/piix.c
index af445db..58532fe 100644
--- a/hw/ide/piix.c
+++ b/hw/ide/piix.c
@@ -90,15 +90,15 @@ static void bmdma_setup_bar(PCIIDEState *d)
 {
     int i;
 
-    memory_region_init(&d->bmdma_bar, NULL, "piix-bmdma-container", 16);
+    memory_region_init(&d->bmdma_bar, OBJECT(d), "piix-bmdma-container", 16);
     for(i = 0;i < 2; i++) {
         BMDMAState *bm = &d->bmdma[i];
 
-        memory_region_init_io(&bm->extra_io, NULL, &piix_bmdma_ops, bm,
+        memory_region_init_io(&bm->extra_io, OBJECT(d), &piix_bmdma_ops, bm,
                               "piix-bmdma", 4);
         memory_region_add_subregion(&d->bmdma_bar, i * 8, &bm->extra_io);
-        memory_region_init_io(&bm->addr_ioport, NULL, &bmdma_addr_ioport_ops, bm,
-                              "bmdma", 4);
+        memory_region_init_io(&bm->addr_ioport, OBJECT(d),
+                              &bmdma_addr_ioport_ops, bm, "bmdma", 4);
         memory_region_add_subregion(&d->bmdma_bar, i * 8 + 4, &bm->addr_ioport);
     }
 }
diff --git a/hw/ide/via.c b/hw/ide/via.c
index 1691717..5a83191 100644
--- a/hw/ide/via.c
+++ b/hw/ide/via.c
@@ -92,15 +92,15 @@ static void bmdma_setup_bar(PCIIDEState *d)
 {
     int i;
 
-    memory_region_init(&d->bmdma_bar, NULL, "via-bmdma-container", 16);
+    memory_region_init(&d->bmdma_bar, OBJECT(d), "via-bmdma-container", 16);
     for(i = 0;i < 2; i++) {
         BMDMAState *bm = &d->bmdma[i];
 
-        memory_region_init_io(&bm->extra_io, NULL, &via_bmdma_ops, bm,
+        memory_region_init_io(&bm->extra_io, OBJECT(d), &via_bmdma_ops, bm,
                               "via-bmdma", 4);
         memory_region_add_subregion(&d->bmdma_bar, i * 8, &bm->extra_io);
-        memory_region_init_io(&bm->addr_ioport, NULL, &bmdma_addr_ioport_ops, bm,
-                              "bmdma", 4);
+        memory_region_init_io(&bm->addr_ioport, OBJECT(d),
+                              &bmdma_addr_ioport_ops, bm, "bmdma", 4);
         memory_region_add_subregion(&d->bmdma_bar, i * 8 + 4, &bm->addr_ioport);
     }
 }
diff --git a/hw/input/milkymist-softusb.c b/hw/input/milkymist-softusb.c
index 69e6485..942cb79 100644
--- a/hw/input/milkymist-softusb.c
+++ b/hw/input/milkymist-softusb.c
@@ -265,17 +265,17 @@ static int milkymist_softusb_init(SysBusDevice *dev)
 
     sysbus_init_irq(dev, &s->irq);
 
-    memory_region_init_io(&s->regs_region, NULL, &softusb_mmio_ops, s,
+    memory_region_init_io(&s->regs_region, OBJECT(s), &softusb_mmio_ops, s,
                           "milkymist-softusb", R_MAX * 4);
     sysbus_init_mmio(dev, &s->regs_region);
 
     /* register pmem and dmem */
-    memory_region_init_ram(&s->pmem, NULL, "milkymist-softusb.pmem",
+    memory_region_init_ram(&s->pmem, OBJECT(s), "milkymist-softusb.pmem",
                            s->pmem_size);
     vmstate_register_ram_global(&s->pmem);
     s->pmem_ptr = memory_region_get_ram_ptr(&s->pmem);
     sysbus_init_mmio(dev, &s->pmem);
-    memory_region_init_ram(&s->dmem, NULL, "milkymist-softusb.dmem",
+    memory_region_init_ram(&s->dmem, OBJECT(s), "milkymist-softusb.dmem",
                            s->dmem_size);
     vmstate_register_ram_global(&s->dmem);
     s->dmem_ptr = memory_region_get_ram_ptr(&s->dmem);
diff --git a/hw/input/pckbd.c b/hw/input/pckbd.c
index 8d1d6a7..ce86237 100644
--- a/hw/input/pckbd.c
+++ b/hw/input/pckbd.c
@@ -494,8 +494,10 @@ static void i8042_initfn(Object *obj)
     ISAKBDState *isa_s = I8042(obj);
     KBDState *s = &isa_s->kbd;
 
-    memory_region_init_io(isa_s->io + 0, NULL, &i8042_data_ops, s, "i8042-data", 1);
-    memory_region_init_io(isa_s->io + 1, NULL, &i8042_cmd_ops, s, "i8042-cmd", 1);
+    memory_region_init_io(isa_s->io + 0, obj, &i8042_data_ops, s,
+                          "i8042-data", 1);
+    memory_region_init_io(isa_s->io + 1, obj, &i8042_cmd_ops, s,
+                          "i8042-cmd", 1);
 }
 
 static void i8042_realizefn(DeviceState *dev, Error **errp)
diff --git a/hw/input/pl050.c b/hw/input/pl050.c
index 871ffba..2312ffc 100644
--- a/hw/input/pl050.c
+++ b/hw/input/pl050.c
@@ -137,7 +137,7 @@ static int pl050_init(SysBusDevice *dev, int is_mouse)
 {
     pl050_state *s = FROM_SYSBUS(pl050_state, dev);
 
-    memory_region_init_io(&s->iomem, NULL, &pl050_ops, s, "pl050", 0x1000);
+    memory_region_init_io(&s->iomem, OBJECT(s), &pl050_ops, s, "pl050", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     sysbus_init_irq(dev, &s->irq);
     s->is_mouse = is_mouse;
diff --git a/hw/intc/apic.c b/hw/intc/apic.c
index d15c8be..5e3b96e 100644
--- a/hw/intc/apic.c
+++ b/hw/intc/apic.c
@@ -873,7 +873,7 @@ static const MemoryRegionOps apic_io_ops = {
 
 static void apic_init(APICCommonState *s)
 {
-    memory_region_init_io(&s->io_memory, NULL, &apic_io_ops, s, "apic-msi",
+    memory_region_init_io(&s->io_memory, OBJECT(s), &apic_io_ops, s, "apic-msi",
                           APIC_SPACE_SIZE);
 
     s->timer = qemu_new_timer_ns(vm_clock, apic_timer, s);
diff --git a/hw/intc/arm_gic.c b/hw/intc/arm_gic.c
index a5ff762..b59df06 100644
--- a/hw/intc/arm_gic.c
+++ b/hw/intc/arm_gic.c
@@ -656,7 +656,8 @@ void gic_init_irqs_and_distributor(GICState *s, int num_irq)
     for (i = 0; i < NUM_CPU(s); i++) {
         sysbus_init_irq(&s->busdev, &s->parent_irq[i]);
     }
-    memory_region_init_io(&s->iomem, NULL, &gic_dist_ops, s, "gic_dist", 0x1000);
+    memory_region_init_io(&s->iomem, OBJECT(s), &gic_dist_ops, s,
+                          "gic_dist", 0x1000);
 }
 
 static void arm_gic_realize(DeviceState *dev, Error **errp)
@@ -682,12 +683,12 @@ static void arm_gic_realize(DeviceState *dev, Error **errp)
      * GIC v2 defines a larger memory region (0x1000) so this will need
      * to be extended when we implement A15.
      */
-    memory_region_init_io(&s->cpuiomem[0], NULL, &gic_thiscpu_ops, s,
+    memory_region_init_io(&s->cpuiomem[0], OBJECT(s), &gic_thiscpu_ops, s,
                           "gic_cpu", 0x100);
     for (i = 0; i < NUM_CPU(s); i++) {
         s->backref[i] = s;
-        memory_region_init_io(&s->cpuiomem[i+1], NULL, &gic_cpu_ops, &s->backref[i],
-                              "gic_cpu", 0x100);
+        memory_region_init_io(&s->cpuiomem[i+1], OBJECT(s), &gic_cpu_ops,
+                              &s->backref[i], "gic_cpu", 0x100);
     }
     /* Distributor */
     sysbus_init_mmio(sbd, &s->iomem);
diff --git a/hw/intc/arm_gic_kvm.c b/hw/intc/arm_gic_kvm.c
index 687d1e2..f713975 100644
--- a/hw/intc/arm_gic_kvm.c
+++ b/hw/intc/arm_gic_kvm.c
@@ -120,7 +120,8 @@ static void kvm_arm_gic_realize(DeviceState *dev, Error **errp)
         sysbus_init_irq(sbd, &s->parent_irq[i]);
     }
     /* Distributor */
-    memory_region_init_reservation(&s->iomem, NULL, "kvm-gic_dist", 0x1000);
+    memory_region_init_reservation(&s->iomem, OBJECT(s),
+                                   "kvm-gic_dist", 0x1000);
     sysbus_init_mmio(sbd, &s->iomem);
     kvm_arm_register_device(&s->iomem,
                             (KVM_ARM_DEVICE_VGIC_V2 << KVM_ARM_DEVICE_ID_SHIFT)
@@ -129,7 +130,8 @@ static void kvm_arm_gic_realize(DeviceState *dev, Error **errp)
      * provide the "interface for core #N" memory regions, because
      * cores with a VGIC don't have those.
      */
-    memory_region_init_reservation(&s->cpuiomem[0], NULL, "kvm-gic_cpu", 0x1000);
+    memory_region_init_reservation(&s->cpuiomem[0], OBJECT(s),
+                                   "kvm-gic_cpu", 0x1000);
     sysbus_init_mmio(sbd, &s->cpuiomem[0]);
     kvm_arm_register_device(&s->cpuiomem[0],
                             (KVM_ARM_DEVICE_VGIC_V2 << KVM_ARM_DEVICE_ID_SHIFT)
diff --git a/hw/intc/armv7m_nvic.c b/hw/intc/armv7m_nvic.c
index 74baa72..2a57f77 100644
--- a/hw/intc/armv7m_nvic.c
+++ b/hw/intc/armv7m_nvic.c
@@ -487,17 +487,18 @@ static void armv7m_nvic_realize(DeviceState *dev, Error **errp)
      * We use overlaying to put the GIC like registers
      * over the top of the system control register region.
      */
-    memory_region_init(&s->container, NULL, "nvic", 0x1000);
+    memory_region_init(&s->container, OBJECT(s), "nvic", 0x1000);
     /* The system register region goes at the bottom of the priority
      * stack as it covers the whole page.
      */
-    memory_region_init_io(&s->sysregmem, NULL, &nvic_sysreg_ops, s,
+    memory_region_init_io(&s->sysregmem, OBJECT(s), &nvic_sysreg_ops, s,
                           "nvic_sysregs", 0x1000);
     memory_region_add_subregion(&s->container, 0, &s->sysregmem);
     /* Alias the GIC region so we can get only the section of it
      * we need, and layer it on top of the system register region.
      */
-    memory_region_init_alias(&s->gic_iomem_alias, NULL, "nvic-gic", &s->gic.iomem,
+    memory_region_init_alias(&s->gic_iomem_alias, OBJECT(s),
+                             "nvic-gic", &s->gic.iomem,
                              0x100, 0xc00);
     memory_region_add_subregion_overlap(&s->container, 0x100,
                                         &s->gic_iomem_alias, 1);
diff --git a/hw/intc/etraxfs_pic.c b/hw/intc/etraxfs_pic.c
index 81e1ab9..ce3a3f6 100644
--- a/hw/intc/etraxfs_pic.c
+++ b/hw/intc/etraxfs_pic.c
@@ -146,7 +146,8 @@ static int etraxfs_pic_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->parent_irq);
     sysbus_init_irq(dev, &s->parent_nmi);
 
-    memory_region_init_io(&s->mmio, NULL, &pic_ops, s, "etraxfs-pic", R_MAX * 4);
+    memory_region_init_io(&s->mmio, OBJECT(s), &pic_ops, s,
+                          "etraxfs-pic", R_MAX * 4);
     sysbus_init_mmio(dev, &s->mmio);
     return 0;
 }
diff --git a/hw/intc/exynos4210_combiner.c b/hw/intc/exynos4210_combiner.c
index 644d6b3..3b40976 100644
--- a/hw/intc/exynos4210_combiner.c
+++ b/hw/intc/exynos4210_combiner.c
@@ -417,7 +417,7 @@ static int exynos4210_combiner_init(SysBusDevice *dev)
         sysbus_init_irq(dev, &s->output_irq[i]);
     }
 
-    memory_region_init_io(&s->iomem, NULL, &exynos4210_combiner_ops, s,
+    memory_region_init_io(&s->iomem, OBJECT(s), &exynos4210_combiner_ops, s,
             "exynos4210-combiner", IIC_REGION_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
 
diff --git a/hw/intc/exynos4210_gic.c b/hw/intc/exynos4210_gic.c
index f9c4218..6147f04 100644
--- a/hw/intc/exynos4210_gic.c
+++ b/hw/intc/exynos4210_gic.c
@@ -299,15 +299,15 @@ static int exynos4210_gic_init(SysBusDevice *dev)
     qdev_init_gpio_in(&s->busdev.qdev, exynos4210_gic_set_irq,
                       EXYNOS4210_GIC_NIRQ - 32);
 
-    memory_region_init(&s->cpu_container, NULL, "exynos4210-cpu-container",
+    memory_region_init(&s->cpu_container, OBJECT(s), "exynos4210-cpu-container",
             EXYNOS4210_EXT_GIC_CPU_REGION_SIZE);
-    memory_region_init(&s->dist_container, NULL, "exynos4210-dist-container",
+    memory_region_init(&s->dist_container, OBJECT(s), "exynos4210-dist-container",
             EXYNOS4210_EXT_GIC_DIST_REGION_SIZE);
 
     for (i = 0; i < s->num_cpu; i++) {
         /* Map CPU interface per SMP Core */
         sprintf(cpu_alias_name, "%s%x", cpu_prefix, i);
-        memory_region_init_alias(&s->cpu_alias[i], NULL,
+        memory_region_init_alias(&s->cpu_alias[i], OBJECT(s),
                                  cpu_alias_name,
                                  sysbus_mmio_get_region(busdev, 1),
                                  0,
@@ -317,7 +317,7 @@ static int exynos4210_gic_init(SysBusDevice *dev)
 
         /* Map Distributor per SMP Core */
         sprintf(dist_alias_name, "%s%x", dist_prefix, i);
-        memory_region_init_alias(&s->dist_alias[i], NULL,
+        memory_region_init_alias(&s->dist_alias[i], OBJECT(s),
                                  dist_alias_name,
                                  sysbus_mmio_get_region(busdev, 0),
                                  0,
diff --git a/hw/intc/grlib_irqmp.c b/hw/intc/grlib_irqmp.c
index f933e6a..181f614 100644
--- a/hw/intc/grlib_irqmp.c
+++ b/hw/intc/grlib_irqmp.c
@@ -344,7 +344,7 @@ static int grlib_irqmp_init(SysBusDevice *dev)
         return -1;
     }
 
-    memory_region_init_io(&irqmp->iomem, NULL, &grlib_irqmp_ops, irqmp,
+    memory_region_init_io(&irqmp->iomem, OBJECT(dev), &grlib_irqmp_ops, irqmp,
                           "irqmp", IRQMP_REG_SIZE);
 
     irqmp->state = g_malloc0(sizeof *irqmp->state);
diff --git a/hw/intc/i8259.c b/hw/intc/i8259.c
index 13250f1..1415bda 100644
--- a/hw/intc/i8259.c
+++ b/hw/intc/i8259.c
@@ -417,8 +417,10 @@ static void pic_realize(DeviceState *dev, Error **err)
     PICCommonState *s = PIC_COMMON(dev);
     PICClass *pc = PIC_GET_CLASS(dev);
 
-    memory_region_init_io(&s->base_io, NULL, &pic_base_ioport_ops, s, "pic", 2);
-    memory_region_init_io(&s->elcr_io, NULL, &pic_elcr_ioport_ops, s, "elcr", 1);
+    memory_region_init_io(&s->base_io, OBJECT(s), &pic_base_ioport_ops, s,
+                          "pic", 2);
+    memory_region_init_io(&s->elcr_io, OBJECT(s), &pic_elcr_ioport_ops, s,
+                          "elcr", 1);
 
     qdev_init_gpio_out(dev, s->int_out, ARRAY_SIZE(s->int_out));
     qdev_init_gpio_in(dev, pic_set_irq, 8);
diff --git a/hw/intc/imx_avic.c b/hw/intc/imx_avic.c
index 870d56f..75c8ffd 100644
--- a/hw/intc/imx_avic.c
+++ b/hw/intc/imx_avic.c
@@ -372,7 +372,8 @@ static int imx_avic_init(SysBusDevice *dev)
 {
     IMXAVICState *s = FROM_SYSBUS(IMXAVICState, dev);
 
-    memory_region_init_io(&s->iomem, NULL, &imx_avic_ops, s, "imx_avic", 0x1000);
+    memory_region_init_io(&s->iomem, OBJECT(s), &imx_avic_ops, s,
+                          "imx_avic", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
 
     qdev_init_gpio_in(&dev->qdev, imx_avic_set_irq, IMX_AVIC_NUM_IRQS);
diff --git a/hw/intc/ioapic.c b/hw/intc/ioapic.c
index 7299b50..5d064fe 100644
--- a/hw/intc/ioapic.c
+++ b/hw/intc/ioapic.c
@@ -227,7 +227,8 @@ static const MemoryRegionOps ioapic_io_ops = {
 
 static void ioapic_init(IOAPICCommonState *s, int instance_no)
 {
-    memory_region_init_io(&s->io_memory, NULL, &ioapic_io_ops, s, "ioapic", 0x1000);
+    memory_region_init_io(&s->io_memory, OBJECT(s), &ioapic_io_ops, s,
+                          "ioapic", 0x1000);
 
     qdev_init_gpio_in(&s->busdev.qdev, ioapic_set_irq, IOAPIC_NUM_PINS);
 
diff --git a/hw/intc/omap_intc.c b/hw/intc/omap_intc.c
index 00cb6ca..bca8585 100644
--- a/hw/intc/omap_intc.c
+++ b/hw/intc/omap_intc.c
@@ -367,7 +367,7 @@ static int omap_intc_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->parent_intr[0]);
     sysbus_init_irq(dev, &s->parent_intr[1]);
     qdev_init_gpio_in(&dev->qdev, omap_set_intr, s->nbanks * 32);
-    memory_region_init_io(&s->mmio, NULL, &omap_inth_mem_ops, s,
+    memory_region_init_io(&s->mmio, OBJECT(s), &omap_inth_mem_ops, s,
                           "omap-intc", s->size);
     sysbus_init_mmio(dev, &s->mmio);
     return 0;
@@ -609,7 +609,7 @@ static int omap2_intc_init(SysBusDevice *dev)
     sysbus_init_irq(dev, &s->parent_intr[0]);
     sysbus_init_irq(dev, &s->parent_intr[1]);
     qdev_init_gpio_in(&dev->qdev, omap_set_intr_noedge, s->nbanks * 32);
-    memory_region_init_io(&s->mmio, NULL, &omap2_inth_mem_ops, s,
+    memory_region_init_io(&s->mmio, OBJECT(s), &omap2_inth_mem_ops, s,
                           "omap2-intc", 0x1000);
     sysbus_init_mmio(dev, &s->mmio);
     return 0;
diff --git a/hw/intc/openpic.c b/hw/intc/openpic.c
index b9e025f..937e292 100644
--- a/hw/intc/openpic.c
+++ b/hw/intc/openpic.c
@@ -1516,8 +1516,8 @@ static void map_list(OpenPICState *opp, const MemReg *list, int *count)
     while (list->name) {
         assert(*count < ARRAY_SIZE(opp->sub_io_mem));
 
-        memory_region_init_io(&opp->sub_io_mem[*count], NULL, list->ops, opp,
-                              list->name, list->size);
+        memory_region_init_io(&opp->sub_io_mem[*count], OBJECT(opp), list->ops,
+                              opp, list->name, list->size);
 
         memory_region_add_subregion(&opp->mem, list->start_addr,
                                     &opp->sub_io_mem[*count]);
@@ -1531,7 +1531,7 @@ static void openpic_init(Object *obj)
 {
     OpenPICState *opp = OPENPIC(obj);
 
-    memory_region_init(&opp->mem, NULL, "openpic", 0x40000);
+    memory_region_init(&opp->mem, obj, "openpic", 0x40000);
 }
 
 static void openpic_realize(DeviceState *dev, Error **errp)
diff --git a/hw/intc/openpic_kvm.c b/hw/intc/openpic_kvm.c
index dc08031..c7f7b84 100644
--- a/hw/intc/openpic_kvm.c
+++ b/hw/intc/openpic_kvm.c
@@ -155,7 +155,7 @@ static void kvm_openpic_init(Object *obj)
 {
     KVMOpenPICState *opp = KVM_OPENPIC(obj);
 
-    memory_region_init_io(&opp->mem, NULL, &kvm_openpic_mem_ops, opp,
+    memory_region_init_io(&opp->mem, OBJECT(opp), &kvm_openpic_mem_ops, opp,
                           "kvm-openpic", 0x40000);
 }
 
diff --git a/hw/intc/pl190.c b/hw/intc/pl190.c
index 5f0f9b7..fdb29d7 100644
--- a/hw/intc/pl190.c
+++ b/hw/intc/pl190.c
@@ -236,7 +236,7 @@ static int pl190_init(SysBusDevice *dev)
 {
     pl190_state *s = FROM_SYSBUS(pl190_state, dev);
 
-    memory_region_init_io(&s->iomem, NULL, &pl190_ops, s, "pl190", 0x1000);
+    memory_region_init_io(&s->iomem, OBJECT(s), &pl190_ops, s, "pl190", 0x1000);
     sysbus_init_mmio(dev, &s->iomem);
     qdev_init_gpio_in(&dev->qdev, pl190_set_irq, 32);
     sysbus_init_irq(dev, &s->irq);
diff --git a/hw/intc/puv3_intc.c b/hw/intc/puv3_intc.c
index b327f0e..44b6651 100644
--- a/hw/intc/puv3_intc.c
+++ b/hw/intc/puv3_intc.c
@@ -106,7 +106,7 @@ static int puv3_intc_init(SysBusDevice *dev)
     s->reg_ICMR = 0;
     s->reg_ICPR = 0;
 
-    memory_region_init_io(&s->iomem, NULL, &puv3_intc_ops, s, "puv3_intc",
+    memory_region_init_io(&s->iomem, OBJECT(s), &puv3_intc_ops, s, "puv3_intc",
             PUV3_REGS_OFFSET);
     sysbus_init_mmio(dev, &s->iomem);
 
diff --git a/hw/intc/realview_gic.c b/hw/intc/realview_gic.c
index 1731a70..e122c2c 100644
--- a/hw/intc/realview_gic.c
+++ b/hw/intc/realview_gic.c
@@ -43,7 +43,8 @@ static int realview_gic_init(SysBusDevice *dev)
     /* Pass through inbound GPIO lines to the GIC */
     qdev_init_gpio_in(&s->busdev.qdev, realview_gic_set_irq, numirq - 32);
 
-    memory_region_init(&s->container, NULL, "realview-gic-container", 0x2000);
+    memory_region_init(&s->container, OBJECT(s),
+                       "realview-gic-container", 0x2000);
     memory_region_add_subregion(&s->container, 0,
                                 sysbus_mmio_get_region(busdev, 1));
     memory_region_add_subregion(&s->container, 0x1000,
diff --git a/hw/intc/slavio_intctl.c b/hw/intc/slavio_intctl.c
index 716e36d..b47d0f0 100644
--- a/hw/intc/slavio_intctl.c
+++ b/hw/intc/slavio_intctl.c
@@ -426,7 +426,7 @@ static int slavio_intctl_init1(SysBusDevice *dev)
     char slave_name[45];
 
     qdev_init_gpio_in(&dev->qdev, slavio_set_irq_all, 32 + MAX_CPUS);
-    memory_region_init_io(&s->iomem, NULL, &slavio_intctlm_mem_ops, s,
+    memory_region_init_io(&s->iomem, OBJECT(s), &slavio_intctlm_mem_ops, s,
                           "master-interrupt-controller", INTCTLM_SIZE);
     sysbus_init_mmio(dev, &s->iomem);
 
@@ -436,7 +436,8 @@ static int slavio_intctl_init1(SysBusDevice *dev)
         for (j = 0; j < MAX_PILS; j++) {
             sysbus_init_irq(dev, &s->cpu_irqs[i][j]);
         }
-        memory_region_init_io(&s->slaves[i].iomem, NULL, &slavio_intctl_mem_ops,
+        memory_region_init_io(&s->slaves[i].iomem, OBJECT(s),
+                              &slavio_intctl_mem_ops,
                               &s->slaves[i], slave_name, INTCTL_SIZE);
         sysbus_init_mmio(dev, &s->slaves[i].iomem);
         s->slaves[i].cpu = i;
diff --git a/hw/intc/xilinx_intc.c b/hw/intc/xilinx_intc.c
index 9ba35f6..25d2057 100644
--- a/hw/intc/xilinx_intc.c
+++ b/hw/intc/xilinx_intc.c
@@ -160,7 +160,8 @@ static int xilinx_intc_init(SysBusDevice *dev)
     qdev_init_gpio_in(&dev->qdev, irq_handler, 32);
     sysbus_init_irq(dev, &p->parent_irq);
 
-    memory_region_init_io(&p->mmio, NULL, &pic_ops, p, "xlnx.xps-intc", R_MAX * 4);
+    memory_region_init_io(&p->mmio, OBJECT(p), &pic_ops, p, "xlnx.xps-intc",
+                          R_MAX * 4);
     sysbus_init_mmio(dev, &p->mmio);
     return 0;
 }
diff --git a/hw/isa/apm.c b/hw/isa/apm.c
index daed6f1..f97e7a0 100644
--- a/hw/isa/apm.c
+++ b/hw/isa/apm.c
@@ -96,7 +96,7 @@ void apm_init(PCIDevice *dev, APMState *apm, apm_ctrl_changed_t callback,
     apm->arg = arg;
 
     /* ioport 0xb2, 0xb3 */
-    memory_region_init_io(&apm->io, NULL, &apm_ops, apm, "apm-io", 2);
+    memory_region_init_io(&apm->io, OBJECT(dev), &apm_ops, apm, "apm-io", 2);
     memory_region_add_subregion(pci_address_space_io(dev), APM_CNT_IOPORT,
                                 &apm->io);
 }
diff --git a/hw/isa/i82378.c b/hw/isa/i82378.c
index 90f36d5..b25ed04 100644
--- a/hw/isa/i82378.c
+++ b/hw/isa/i82378.c
@@ -221,10 +221,12 @@ static int pci_i82378_init(PCIDevice *dev)
 
     pci_conf[PCI_INTERRUPT_PIN] = 1; /* interrupt pin 0 */
 
-    memory_region_init_io(&s->io, NULL, &i82378_io_ops, s, "i82378-io", 0x00010000);
+    memory_region_init_io(&s->io, OBJECT(pci), &i82378_io_ops, s,
+                          "i82378-io", 0x00010000);
     pci_register_bar(dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY, &s->io);
 
-    memory_region_init_io(&s->mem, NULL, &i82378_mem_ops, s, "i82378-mem", 0x01000000);
+    memory_region_init_io(&s->mem, OBJECT(pci), &i82378_mem_ops, s,
+                          "i82378-mem", 0x01000000);
     pci_register_bar(dev, 1, PCI_BASE_ADDRESS_SPACE_MEMORY, &s->mem);
 
     /* Make I/O address read only */
diff --git a/hw/isa/lpc_ich9.c b/hw/isa/lpc_ich9.c
index f704c42..b49be4d 100644
--- a/hw/isa/lpc_ich9.c
+++ b/hw/isa/lpc_ich9.c
@@ -535,7 +535,7 @@ static int ich9_lpc_initfn(PCIDevice *d)
     pci_set_long(d->wmask + ICH9_LPC_PMBASE,
                  ICH9_LPC_PMBASE_BASE_ADDRESS_MASK);
 
-    memory_region_init_io(&lpc->rbca_mem, NULL, &rbca_mmio_ops, lpc,
+    memory_region_init_io(&lpc->rbca_mem, OBJECT(d), &rbca_mmio_ops, lpc,
                             "lpc-rbca-mmio", ICH9_CC_SIZE);
 
     lpc->isa_bus = isa_bus;
@@ -546,7 +546,7 @@ static int ich9_lpc_initfn(PCIDevice *d)
     lpc->machine_ready.notify = ich9_lpc_machine_ready;
     qemu_add_machine_init_done_notifier(&lpc->machine_ready);
 
-    memory_region_init_io(&lpc->rst_cnt_mem, NULL, &ich9_rst_cnt_ops, lpc,
+    memory_region_init_io(&lpc->rst_cnt_mem, OBJECT(d), &ich9_rst_cnt_ops, lpc,
                           "lpc-reset-control", 1);
     memory_region_add_subregion_overlap(pci_address_space_io(d),
                                         ICH9_RST_CNT_IOPORT, &lpc->rst_cnt_mem,
diff --git a/hw/isa/pc87312.c b/hw/isa/pc87312.c
index 7b3e7fb..46a23fb 100644
--- a/hw/isa/pc87312.c
+++ b/hw/isa/pc87312.c
@@ -352,7 +352,7 @@ static void pc87312_initfn(Object *obj)
 {
     PC87312State *s = PC87312(obj);
 
-    memory_region_init_io(&s->io, NULL, &pc87312_io_ops, s, "pc87312", 2);
+    memory_region_init_io(&s->io, obj, &pc87312_io_ops, s, "pc87312", 2);
 }
 
 static const VMStateDescription vmstate_pc87312 = {
diff --git a/hw/isa/vt82c686.c b/hw/isa/vt82c686.c
index 19c887d..2174eaa 100644
--- a/hw/isa/vt82c686.c
+++ b/hw/isa/vt82c686.c
@@ -356,7 +356,7 @@ static int vt82c686b_pm_initfn(PCIDevice *dev)
 
     apm_init(dev, &s->apm, NULL, s);
 
-    memory_region_init(&s->io, NULL, "vt82c686-pm", 64);
+    memory_region_init(&s->io, OBJECT(dev), "vt82c686-pm", 64);
     memory_region_set_enabled(&s->io, false);
     memory_region_add_subregion(get_system_io(), 0, &s->io);
 
