diff --git a/hw/a9scu.c b/hw/a9scu.c
index 0e9e54d..a3f6bfb 100644
--- a/hw/a9scu.c
+++ b/hw/a9scu.c
@@ -147,6 +147,7 @@ static void a9_scu_class_init(ObjectClass *klass, void *data)
     dc->props = a9_scu_properties;
     dc->vmsd = &vmstate_a9_scu;
     dc->reset = a9_scu_reset;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo a9_scu_info = {
diff --git a/hw/apb_pci.c b/hw/apb_pci.c
index 7eb0c2b..9198de7 100644
--- a/hw/apb_pci.c
+++ b/hw/apb_pci.c
@@ -500,6 +500,7 @@ static void pbm_host_class_init(ObjectClass *klass, void *data)
 
     k->init = pci_pbm_init_device;
     dc->reset = pci_pbm_reset;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pbm_host_info = {
diff --git a/hw/arm_sysctl.c b/hw/arm_sysctl.c
index 7ecb7da..391709a 100644
--- a/hw/arm_sysctl.c
+++ b/hw/arm_sysctl.c
@@ -411,6 +411,7 @@ static void arm_sysctl_class_init(ObjectClass *klass, void *data)
     dc->reset = arm_sysctl_reset;
     dc->vmsd = &vmstate_arm_sysctl;
     dc->props = arm_sysctl_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo arm_sysctl_info = {
diff --git a/hw/arm_timer.c b/hw/arm_timer.c
index c1e56be..5d7182a 100644
--- a/hw/arm_timer.c
+++ b/hw/arm_timer.c
@@ -359,6 +359,7 @@ static void icp_pit_class_init(ObjectClass *klass, void *data)
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
 
     sdc->init = icp_pit_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo icp_pit_info = {
@@ -381,6 +382,7 @@ static void sp804_class_init(ObjectClass *klass, void *data)
 
     sdc->init = sp804_init;
     k->props = sp804_properties;
+    k->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo sp804_info = {
diff --git a/hw/armv7m.c b/hw/armv7m.c
index 904696c..f9da127 100644
--- a/hw/armv7m.c
+++ b/hw/armv7m.c
@@ -267,6 +267,7 @@ static void bitband_class_init(ObjectClass *klass, void *data)
 
     k->init = bitband_init;
     dc->props = bitband_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo bitband_info = {
diff --git a/hw/bitbang_i2c.c b/hw/bitbang_i2c.c
index 114508f..a153a98 100644
--- a/hw/bitbang_i2c.c
+++ b/hw/bitbang_i2c.c
@@ -228,6 +228,7 @@ static void gpio_i2c_class_init(ObjectClass *klass, void *data)
 
     k->init = gpio_i2c_init;
     dc->desc = "Virtual GPIO to I2C bridge";
+    dc->no_user = 1; /* for gpio pins */
 }
 
 static const TypeInfo gpio_i2c_info = {
diff --git a/hw/cadence_ttc.c b/hw/cadence_ttc.c
index 67028a3..7a7aff4 100644
--- a/hw/cadence_ttc.c
+++ b/hw/cadence_ttc.c
@@ -472,6 +472,7 @@ static void cadence_ttc_class_init(ObjectClass *klass, void *data)
 
     sdc->init = cadence_ttc_init;
     dc->vmsd = &vmstate_cadence_ttc;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo cadence_ttc_info = {
diff --git a/hw/cadence_uart.c b/hw/cadence_uart.c
index 5766d38..7d40d0e 100644
--- a/hw/cadence_uart.c
+++ b/hw/cadence_uart.c
@@ -500,6 +500,7 @@ static void cadence_uart_class_init(ObjectClass *klass, void *data)
 
     sdc->init = cadence_uart_init;
     dc->vmsd = &vmstate_cadence_uart;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo cadence_uart_info = {
diff --git a/hw/cs4231.c b/hw/cs4231.c
index ae384b9..ce7c020 100644
--- a/hw/cs4231.c
+++ b/hw/cs4231.c
@@ -164,6 +164,7 @@ static void cs4231_class_init(ObjectClass *klass, void *data)
     dc->reset = cs_reset;
     dc->vmsd = &vmstate_cs4231;
     dc->props = cs4231_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo cs4231_info = {
diff --git a/hw/ds1225y.c b/hw/ds1225y.c
index a6219a7..cb5b835 100644
--- a/hw/ds1225y.c
+++ b/hw/ds1225y.c
@@ -148,6 +148,7 @@ static void nvram_sysbus_class_init(ObjectClass *klass, void *data)
     k->init = nvram_sysbus_initfn;
     dc->vmsd = &vmstate_nvram;
     dc->props = nvram_sysbus_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo nvram_sysbus_info = {
diff --git a/hw/eccmemctl.c b/hw/eccmemctl.c
index dbac2c2..6f28a6b 100644
--- a/hw/eccmemctl.c
+++ b/hw/eccmemctl.c
@@ -322,6 +322,7 @@ static void ecc_class_init(ObjectClass *klass, void *data)
     dc->reset = ecc_reset;
     dc->vmsd = &vmstate_ecc;
     dc->props = ecc_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo ecc_info = {
diff --git a/hw/empty_slot.c b/hw/empty_slot.c
index d7b5497..8802ca7 100644
--- a/hw/empty_slot.c
+++ b/hw/empty_slot.c
@@ -81,6 +81,7 @@ static void empty_slot_class_init(ObjectClass *klass, void *data)
     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
 
     k->init = empty_slot_init1;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo empty_slot_info = {
diff --git a/hw/escc.c b/hw/escc.c
index 18c0292..49fabf0 100644
--- a/hw/escc.c
+++ b/hw/escc.c
@@ -921,6 +921,7 @@ static void escc_class_init(ObjectClass *klass, void *data)
     dc->reset = escc_reset;
     dc->vmsd = &vmstate_escc;
     dc->props = escc_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo escc_info = {
diff --git a/hw/esp.c b/hw/esp.c
index 2af48aa..723c221 100644
--- a/hw/esp.c
+++ b/hw/esp.c
@@ -710,6 +710,7 @@ static void sysbus_esp_class_init(ObjectClass *klass, void *data)
     k->init = sysbus_esp_init;
     dc->reset = sysbus_esp_hard_reset;
     dc->vmsd = &vmstate_sysbus_esp_scsi;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo sysbus_esp_info = {
diff --git a/hw/etraxfs_pic.c b/hw/etraxfs_pic.c
index 64af31c..156f006 100644
--- a/hw/etraxfs_pic.c
+++ b/hw/etraxfs_pic.c
@@ -163,6 +163,7 @@ static void etraxfs_pic_class_init(ObjectClass *klass, void *data)
 
     k->init = etraxfs_pic_init;
     dc->props = etraxfs_pic_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo etraxfs_pic_info = {
diff --git a/hw/etraxfs_ser.c b/hw/etraxfs_ser.c
index 72c8868..b3ca719 100644
--- a/hw/etraxfs_ser.c
+++ b/hw/etraxfs_ser.c
@@ -231,6 +231,7 @@ static void etraxfs_ser_class_init(ObjectClass *klass, void *data)
 
     k->init = etraxfs_ser_init;
     dc->reset = etraxfs_ser_reset;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo etraxfs_ser_info = {
diff --git a/hw/etraxfs_timer.c b/hw/etraxfs_timer.c
index d3dac52..cc503cb 100644
--- a/hw/etraxfs_timer.c
+++ b/hw/etraxfs_timer.c
@@ -334,6 +334,7 @@ static void etraxfs_timer_class_init(ObjectClass *klass, void *data)
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
 
     sdc->init = etraxfs_timer_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo etraxfs_timer_info = {
diff --git a/hw/exynos4210_combiner.c b/hw/exynos4210_combiner.c
index ba644b4..6caae38 100644
--- a/hw/exynos4210_combiner.c
+++ b/hw/exynos4210_combiner.c
@@ -438,6 +438,7 @@ static void exynos4210_combiner_class_init(ObjectClass *klass, void *data)
     dc->reset = exynos4210_combiner_reset;
     dc->props = exynos4210_combiner_properties;
     dc->vmsd = &vmstate_exynos4210_combiner;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo exynos4210_combiner_info = {
diff --git a/hw/exynos4210_fimd.c b/hw/exynos4210_fimd.c
index 3d498b7..be946d4 100644
--- a/hw/exynos4210_fimd.c
+++ b/hw/exynos4210_fimd.c
@@ -1910,6 +1910,7 @@ static void exynos4210_fimd_class_init(ObjectClass *klass, void *data)
 
     dc->vmsd = &exynos4210_fimd_vmstate;
     dc->reset = exynos4210_fimd_reset;
+    dc->no_user = 1; /* for sysbus mmio/irq */
     k->init = exynos4210_fimd_init;
 }
 
diff --git a/hw/exynos4210_gic.c b/hw/exynos4210_gic.c
index 94b138f..8a47ead 100644
--- a/hw/exynos4210_gic.c
+++ b/hw/exynos4210_gic.c
@@ -344,6 +344,7 @@ static void exynos4210_gic_class_init(ObjectClass *klass, void *data)
 
     k->init = exynos4210_gic_init;
     dc->props = exynos4210_gic_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo exynos4210_gic_info = {
@@ -445,6 +446,7 @@ static void exynos4210_irq_gate_class_init(ObjectClass *klass, void *data)
     dc->reset = exynos4210_irq_gate_reset;
     dc->vmsd = &vmstate_exynos4210_irq_gate;
     dc->props = exynos4210_irq_gate_properties;
+    dc->no_user = 1; /* for sysbus irq */
 }
 
 static const TypeInfo exynos4210_irq_gate_info = {
diff --git a/hw/exynos4210_i2c.c b/hw/exynos4210_i2c.c
index cefd736..c546aa6 100644
--- a/hw/exynos4210_i2c.c
+++ b/hw/exynos4210_i2c.c
@@ -316,6 +316,7 @@ static void exynos4210_i2c_class_init(ObjectClass *klass, void *data)
 
     dc->vmsd = &exynos4210_i2c_vmstate;
     dc->reset = exynos4210_i2c_reset;
+    dc->no_user = 1; /* for sysbus mmio/irq */
     sbdc->init = exynos4210_i2c_realize;
 }
 
diff --git a/hw/exynos4210_mct.c b/hw/exynos4210_mct.c
index d7d5904..5c66db3 100644
--- a/hw/exynos4210_mct.c
+++ b/hw/exynos4210_mct.c
@@ -1465,6 +1465,7 @@ static void exynos4210_mct_class_init(ObjectClass *klass, void *data)
     k->init = exynos4210_mct_init;
     dc->reset = exynos4210_mct_reset;
     dc->vmsd = &vmstate_exynos4210_mct_state;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo exynos4210_mct_info = {
diff --git a/hw/exynos4210_pmu.c b/hw/exynos4210_pmu.c
index 7c81a1b..23225ca 100644
--- a/hw/exynos4210_pmu.c
+++ b/hw/exynos4210_pmu.c
@@ -482,6 +482,7 @@ static void exynos4210_pmu_class_init(ObjectClass *klass, void *data)
     k->init = exynos4210_pmu_init;
     dc->reset = exynos4210_pmu_reset;
     dc->vmsd = &exynos4210_pmu_vmstate;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo exynos4210_pmu_info = {
diff --git a/hw/exynos4210_pwm.c b/hw/exynos4210_pwm.c
index c865624..1b2fd7d 100644
--- a/hw/exynos4210_pwm.c
+++ b/hw/exynos4210_pwm.c
@@ -405,6 +405,7 @@ static void exynos4210_pwm_class_init(ObjectClass *klass, void *data)
     k->init = exynos4210_pwm_init;
     dc->reset = exynos4210_pwm_reset;
     dc->vmsd = &vmstate_exynos4210_pwm_state;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo exynos4210_pwm_info = {
diff --git a/hw/exynos4210_rtc.c b/hw/exynos4210_rtc.c
index 5694a62..b83dfca 100644
--- a/hw/exynos4210_rtc.c
+++ b/hw/exynos4210_rtc.c
@@ -575,6 +575,7 @@ static void exynos4210_rtc_class_init(ObjectClass *klass, void *data)
     k->init = exynos4210_rtc_init;
     dc->reset = exynos4210_rtc_reset;
     dc->vmsd = &vmstate_exynos4210_rtc_state;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo exynos4210_rtc_info = {
diff --git a/hw/exynos4210_uart.c b/hw/exynos4210_uart.c
index bdf797a..8fbd4b8 100644
--- a/hw/exynos4210_uart.c
+++ b/hw/exynos4210_uart.c
@@ -659,6 +659,7 @@ static void exynos4210_uart_class_init(ObjectClass *klass, void *data)
     dc->reset = exynos4210_uart_reset;
     dc->props = exynos4210_uart_properties;
     dc->vmsd = &vmstate_exynos4210_uart;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo exynos4210_uart_info = {
diff --git a/hw/fdc.c b/hw/fdc.c
index 976a587..7fa3576 100644
--- a/hw/fdc.c
+++ b/hw/fdc.c
@@ -2242,6 +2242,7 @@ static void sysbus_fdc_class_init(ObjectClass *klass, void *data)
     dc->reset = fdctrl_external_reset_sysbus;
     dc->vmsd = &vmstate_sysbus_fdc;
     dc->props = sysbus_fdc_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo sysbus_fdc_info = {
@@ -2265,6 +2266,7 @@ static void sun4m_fdc_class_init(ObjectClass *klass, void *data)
     dc->reset = fdctrl_external_reset_sysbus;
     dc->vmsd = &vmstate_sysbus_fdc;
     dc->props = sun4m_fdc_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo sun4m_fdc_info = {
diff --git a/hw/g364fb.c b/hw/g364fb.c
index 0c0c8ba..e897838 100644
--- a/hw/g364fb.c
+++ b/hw/g364fb.c
@@ -595,6 +595,7 @@ static void g364fb_sysbus_class_init(ObjectClass *klass, void *data)
     dc->reset = g364fb_sysbus_reset;
     dc->vmsd = &vmstate_g364fb;
     dc->props = g364fb_sysbus_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo g364fb_sysbus_info = {
diff --git a/hw/ide/ahci.c b/hw/ide/ahci.c
index ad0094f..f27c05e 100644
--- a/hw/ide/ahci.c
+++ b/hw/ide/ahci.c
@@ -1321,6 +1321,7 @@ static void sysbus_ahci_class_init(ObjectClass *klass, void *data)
     dc->vmsd = &vmstate_sysbus_ahci;
     dc->props = sysbus_ahci_properties;
     dc->reset = sysbus_ahci_reset;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo sysbus_ahci_info = {
diff --git a/hw/imx_avic.c b/hw/imx_avic.c
index f1f066c..9a4a019 100644
--- a/hw/imx_avic.c
+++ b/hw/imx_avic.c
@@ -391,6 +391,7 @@ static void imx_avic_class_init(ObjectClass *klass, void *data)
     dc->vmsd = &vmstate_imx_avic;
     dc->reset = imx_avic_reset;
     dc->desc = "i.MX Advanced Vector Interrupt Controller";
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo imx_avic_info = {
diff --git a/hw/imx_ccm.c b/hw/imx_ccm.c
index 477903a..e20f339 100644
--- a/hw/imx_ccm.c
+++ b/hw/imx_ccm.c
@@ -304,6 +304,7 @@ static void imx_ccm_class_init(ObjectClass *klass, void *data)
     dc->reset = imx_ccm_reset;
     dc->vmsd = &vmstate_imx_ccm;
     dc->desc = "i.MX Clock Control Module";
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo imx_ccm_info = {
diff --git a/hw/imx_serial.c b/hw/imx_serial.c
index 2d8253e..24fd96f 100644
--- a/hw/imx_serial.c
+++ b/hw/imx_serial.c
@@ -450,6 +450,7 @@ static void imx_serial_class_init(ObjectClass *klass, void *data)
     dc->reset = imx_serial_reset_at_boot;
     dc->desc = "i.MX series UART";
     dc->props = imx32_serial_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo imx_serial_info = {
diff --git a/hw/imx_timer.c b/hw/imx_timer.c
index e924c74..feba982 100644
--- a/hw/imx_timer.c
+++ b/hw/imx_timer.c
@@ -654,6 +654,7 @@ static void imx_timerg_class_init(ObjectClass *klass, void *data)
     dc->vmsd = &vmstate_imx_timerg;
     dc->reset = imx_timerg_reset;
     dc->desc = "i.MX general timer";
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static void imx_timerp_class_init(ObjectClass *klass, void *data)
@@ -664,6 +665,7 @@ static void imx_timerp_class_init(ObjectClass *klass, void *data)
     dc->vmsd = &vmstate_imx_timerp;
     dc->reset = imx_timerp_reset;
     dc->desc = "i.MX periodic timer";
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo imx_timerp_info = {
diff --git a/hw/integratorcp.c b/hw/integratorcp.c
index 9e3630a..dd8cd1d 100644
--- a/hw/integratorcp.c
+++ b/hw/integratorcp.c
@@ -534,6 +534,7 @@ static void core_class_init(ObjectClass *klass, void *data)
 
     k->init = integratorcm_init;
     dc->props = core_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo core_info = {
diff --git a/hw/jazz_led.c b/hw/jazz_led.c
index 4822c48..4e6dfd9 100644
--- a/hw/jazz_led.c
+++ b/hw/jazz_led.c
@@ -275,6 +275,7 @@ static void jazz_led_class_init(ObjectClass *klass, void *data)
     dc->desc = "Jazz LED display",
     dc->vmsd = &vmstate_jazz_led;
     dc->reset = jazz_led_reset;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo jazz_led_info = {
diff --git a/hw/lan9118.c b/hw/lan9118.c
index 0e844e5..16bff88 100644
--- a/hw/lan9118.c
+++ b/hw/lan9118.c
@@ -1366,6 +1366,7 @@ static void lan9118_class_init(ObjectClass *klass, void *data)
     dc->reset = lan9118_reset;
     dc->props = lan9118_properties;
     dc->vmsd = &vmstate_lan9118;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo lan9118_info = {
diff --git a/hw/lm32_timer.c b/hw/lm32_timer.c
index db527e9..6da6ace 100644
--- a/hw/lm32_timer.c
+++ b/hw/lm32_timer.c
@@ -213,6 +213,7 @@ static void lm32_timer_class_init(ObjectClass *klass, void *data)
     dc->reset = timer_reset;
     dc->vmsd = &vmstate_lm32_timer;
     dc->props = lm32_timer_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo lm32_timer_info = {
diff --git a/hw/lm32_uart.c b/hw/lm32_uart.c
index 9c89cca..94f6aa6 100644
--- a/hw/lm32_uart.c
+++ b/hw/lm32_uart.c
@@ -279,6 +279,7 @@ static void lm32_uart_class_init(ObjectClass *klass, void *data)
     k->init = lm32_uart_init;
     dc->reset = uart_reset;
     dc->vmsd = &vmstate_lm32_uart;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo lm32_uart_info = {
diff --git a/hw/marvell_88w8618_audio.c b/hw/marvell_88w8618_audio.c
index c792caf..2915844 100644
--- a/hw/marvell_88w8618_audio.c
+++ b/hw/marvell_88w8618_audio.c
@@ -286,6 +286,7 @@ static void mv88w8618_audio_class_init(ObjectClass *klass, void *data)
     dc->reset = mv88w8618_audio_reset;
     dc->vmsd = &mv88w8618_audio_vmsd;
     dc->props = mv88w8618_audio_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo mv88w8618_audio_info = {
diff --git a/hw/milkymist-ac97.c b/hw/milkymist-ac97.c
index d51d1ac..f6e8730 100644
--- a/hw/milkymist-ac97.c
+++ b/hw/milkymist-ac97.c
@@ -327,6 +327,7 @@ static void milkymist_ac97_class_init(ObjectClass *klass, void *data)
     k->init = milkymist_ac97_init;
     dc->reset = milkymist_ac97_reset;
     dc->vmsd = &vmstate_milkymist_ac97;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo milkymist_ac97_info = {
diff --git a/hw/milkymist-hpdmc.c b/hw/milkymist-hpdmc.c
index ea4d210..5f77d67 100644
--- a/hw/milkymist-hpdmc.c
+++ b/hw/milkymist-hpdmc.c
@@ -153,6 +153,7 @@ static void milkymist_hpdmc_class_init(ObjectClass *klass, void *data)
     k->init = milkymist_hpdmc_init;
     dc->reset = milkymist_hpdmc_reset;
     dc->vmsd = &vmstate_milkymist_hpdmc;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo milkymist_hpdmc_info = {
diff --git a/hw/milkymist-memcard.c b/hw/milkymist-memcard.c
index 9d15309..8fc44b4 100644
--- a/hw/milkymist-memcard.c
+++ b/hw/milkymist-memcard.c
@@ -286,6 +286,7 @@ static void milkymist_memcard_class_init(ObjectClass *klass, void *data)
     k->init = milkymist_memcard_init;
     dc->reset = milkymist_memcard_reset;
     dc->vmsd = &vmstate_milkymist_memcard;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo milkymist_memcard_info = {
diff --git a/hw/milkymist-minimac2.c b/hw/milkymist-minimac2.c
index 9992dcc..7875bd8 100644
--- a/hw/milkymist-minimac2.c
+++ b/hw/milkymist-minimac2.c
@@ -533,6 +533,7 @@ static void milkymist_minimac2_class_init(ObjectClass *klass, void *data)
     dc->reset = milkymist_minimac2_reset;
     dc->vmsd = &vmstate_milkymist_minimac2;
     dc->props = milkymist_minimac2_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo milkymist_minimac2_info = {
diff --git a/hw/milkymist-softusb.c b/hw/milkymist-softusb.c
index 01660be..3dc6438 100644
--- a/hw/milkymist-softusb.c
+++ b/hw/milkymist-softusb.c
@@ -314,6 +314,7 @@ static void milkymist_softusb_class_init(ObjectClass *klass, void *data)
     dc->reset = milkymist_softusb_reset;
     dc->vmsd = &vmstate_milkymist_softusb;
     dc->props = milkymist_softusb_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo milkymist_softusb_info = {
diff --git a/hw/mipsnet.c b/hw/mipsnet.c
index ff6bf7f..5887bb2 100644
--- a/hw/mipsnet.c
+++ b/hw/mipsnet.c
@@ -267,6 +267,7 @@ static void mipsnet_class_init(ObjectClass *klass, void *data)
     dc->reset = mipsnet_sysbus_reset;
     dc->vmsd = &vmstate_mipsnet;
     dc->props = mipsnet_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo mipsnet_info = {
diff --git a/hw/mpc8544_guts.c b/hw/mpc8544_guts.c
index 728723c..de6d037 100644
--- a/hw/mpc8544_guts.c
+++ b/hw/mpc8544_guts.c
@@ -126,6 +126,7 @@ static void mpc8544_guts_class_init(ObjectClass *klass, void *data)
     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
 
     k->init = mpc8544_guts_initfn;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo mpc8544_guts_info = {
diff --git a/hw/mst_fpga.c b/hw/mst_fpga.c
index 7ae05e3..0a5fe7e 100644
--- a/hw/mst_fpga.c
+++ b/hw/mst_fpga.c
@@ -246,6 +246,7 @@ static void mst_fpga_class_init(ObjectClass *klass, void *data)
     k->init = mst_fpga_init;
     dc->desc = "Mainstone II FPGA";
     dc->vmsd = &vmstate_mst_fpga_regs;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo mst_fpga_info = {
diff --git a/hw/musicpal.c b/hw/musicpal.c
index 272cb80..e844daf 100644
--- a/hw/musicpal.c
+++ b/hw/musicpal.c
@@ -641,6 +641,7 @@ static void musicpal_lcd_class_init(ObjectClass *klass, void *data)
 
     k->init = musicpal_lcd_init;
     dc->vmsd = &musicpal_lcd_vmsd;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo musicpal_lcd_info = {
@@ -760,6 +761,7 @@ static void mv88w8618_pic_class_init(ObjectClass *klass, void *data)
     k->init = mv88w8618_pic_init;
     dc->reset = mv88w8618_pic_reset;
     dc->vmsd = &mv88w8618_pic_vmsd;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo mv88w8618_pic_info = {
@@ -937,6 +939,7 @@ static void mv88w8618_pit_class_init(ObjectClass *klass, void *data)
     k->init = mv88w8618_pit_init;
     dc->reset = mv88w8618_pit_reset;
     dc->vmsd = &mv88w8618_pit_vmsd;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo mv88w8618_pit_info = {
@@ -1017,6 +1020,7 @@ static void mv88w8618_flashcfg_class_init(ObjectClass *klass, void *data)
 
     k->init = mv88w8618_flashcfg_init;
     dc->vmsd = &mv88w8618_flashcfg_vmsd;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo mv88w8618_flashcfg_info = {
@@ -1339,6 +1343,7 @@ static void musicpal_gpio_class_init(ObjectClass *klass, void *data)
     k->init = musicpal_gpio_init;
     dc->reset = musicpal_gpio_reset;
     dc->vmsd = &musicpal_gpio_vmsd;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo musicpal_gpio_info = {
@@ -1493,6 +1498,7 @@ static void musicpal_key_class_init(ObjectClass *klass, void *data)
 
     k->init = musicpal_key_init;
     dc->vmsd = &musicpal_key_vmsd;
+    dc->no_user = 1; /* for gpio */
 }
 
 static const TypeInfo musicpal_key_info = {
@@ -1671,8 +1677,10 @@ machine_init(musicpal_machine_init);
 static void mv88w8618_wlan_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sdc->init = mv88w8618_wlan_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo mv88w8618_wlan_info = {
diff --git a/hw/omap_gpio.c b/hw/omap_gpio.c
index aadf1cc..2d81a6a 100644
--- a/hw/omap_gpio.c
+++ b/hw/omap_gpio.c
@@ -745,6 +745,7 @@ static void omap_gpio_class_init(ObjectClass *klass, void *data)
     k->init = omap_gpio_init;
     dc->reset = omap_gpif_reset;
     dc->props = omap_gpio_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo omap_gpio_info = {
@@ -774,6 +775,7 @@ static void omap2_gpio_class_init(ObjectClass *klass, void *data)
     k->init = omap2_gpio_init;
     dc->reset = omap2_gpif_reset;
     dc->props = omap2_gpio_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo omap2_gpio_info = {
diff --git a/hw/omap_i2c.c b/hw/omap_i2c.c
index 143b198..8f8c738 100644
--- a/hw/omap_i2c.c
+++ b/hw/omap_i2c.c
@@ -469,6 +469,7 @@ static void omap_i2c_class_init(ObjectClass *klass, void *data)
     k->init = omap_i2c_init;
     dc->props = omap_i2c_properties;
     dc->reset = omap_i2c_reset;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo omap_i2c_info = {
diff --git a/hw/omap_intc.c b/hw/omap_intc.c
index 4b0acd0..37c1965 100644
--- a/hw/omap_intc.c
+++ b/hw/omap_intc.c
@@ -387,6 +387,7 @@ static void omap_intc_class_init(ObjectClass *klass, void *data)
     k->init = omap_intc_init;
     dc->reset = omap_inth_reset;
     dc->props = omap_intc_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo omap_intc_info = {
@@ -631,6 +632,7 @@ static void omap2_intc_class_init(ObjectClass *klass, void *data)
     k->init = omap2_intc_init;
     dc->reset = omap_inth_reset;
     dc->props = omap2_intc_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo omap2_intc_info = {
diff --git a/hw/onenand.c b/hw/onenand.c
index 00a8738..ab70ca0 100644
--- a/hw/onenand.c
+++ b/hw/onenand.c
@@ -819,6 +819,7 @@ static void onenand_class_init(ObjectClass *klass, void *data)
     k->init = onenand_initfn;
     dc->reset = onenand_system_reset;
     dc->props = onenand_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo onenand_info = {
diff --git a/hw/opencores_eth.c b/hw/opencores_eth.c
index f9ba5ee..5f93475 100644
--- a/hw/opencores_eth.c
+++ b/hw/opencores_eth.c
@@ -716,6 +716,7 @@ static void open_eth_class_init(ObjectClass *klass, void *data)
     dc->desc = "Opencores 10/100 Mbit Ethernet";
     dc->reset = qdev_open_eth_reset;
     dc->props = open_eth_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo open_eth_info = {
diff --git a/hw/openpic.c b/hw/openpic.c
index 20a479c..07dfd59 100644
--- a/hw/openpic.c
+++ b/hw/openpic.c
@@ -1644,6 +1644,7 @@ static void openpic_class_init(ObjectClass *klass, void *data)
     k->init = openpic_init;
     dc->props = openpic_properties;
     dc->reset = openpic_reset;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo openpic_info = {
diff --git a/hw/pc_sysfw.c b/hw/pc_sysfw.c
index 7f6c12c..785e7f4 100644
--- a/hw/pc_sysfw.c
+++ b/hw/pc_sysfw.c
@@ -254,6 +254,7 @@ static void pcsysfw_class_init (ObjectClass *klass, void *data)
     dc->desc = "PC System Firmware";
     dc->init = pcsysfw_init;
     dc->props = pcsysfw_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pcsysfw_info = {
diff --git a/hw/pflash_cfi01.c b/hw/pflash_cfi01.c
index 123b006..0524cc8 100644
--- a/hw/pflash_cfi01.c
+++ b/hw/pflash_cfi01.c
@@ -707,6 +707,7 @@ static void pflash_cfi01_class_init(ObjectClass *klass, void *data)
 
     k->init = pflash_cfi01_init;
     dc->props = pflash_cfi01_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 
diff --git a/hw/pflash_cfi02.c b/hw/pflash_cfi02.c
index 44bd465..ee1c530 100644
--- a/hw/pflash_cfi02.c
+++ b/hw/pflash_cfi02.c
@@ -734,6 +734,7 @@ static void pflash_cfi02_class_init(ObjectClass *klass, void *data)
 
     k->init = pflash_cfi02_init;
     dc->props = pflash_cfi02_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pflash_cfi02_info = {
diff --git a/hw/pl011.c b/hw/pl011.c
index 002a50e..2910684 100644
--- a/hw/pl011.c
+++ b/hw/pl011.c
@@ -296,8 +296,10 @@ static int pl011_luminary_init(SysBusDevice *dev)
 static void pl011_arm_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sdc->init = pl011_arm_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pl011_arm_info = {
@@ -310,8 +312,10 @@ static const TypeInfo pl011_arm_info = {
 static void pl011_luminary_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sdc->init = pl011_luminary_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pl011_luminary_info = {
diff --git a/hw/pl022.c b/hw/pl022.c
index c160e90..2159cc4 100644
--- a/hw/pl022.c
+++ b/hw/pl022.c
@@ -291,6 +291,7 @@ static void pl022_class_init(ObjectClass *klass, void *data)
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
 
     sdc->init = pl022_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pl022_info = {
diff --git a/hw/pl050.c b/hw/pl050.c
index 5d06bc9..d3efdd9 100644
--- a/hw/pl050.c
+++ b/hw/pl050.c
@@ -166,6 +166,7 @@ static void pl050_kbd_class_init(ObjectClass *klass, void *data)
 
     k->init = pl050_init_keyboard;
     dc->vmsd = &vmstate_pl050;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pl050_kbd_info = {
@@ -182,6 +183,7 @@ static void pl050_mouse_class_init(ObjectClass *klass, void *data)
 
     k->init = pl050_init_mouse;
     dc->vmsd = &vmstate_pl050;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pl050_mouse_info = {
diff --git a/hw/pl061.c b/hw/pl061.c
index a78e819..c919f56 100644
--- a/hw/pl061.c
+++ b/hw/pl061.c
@@ -302,6 +302,7 @@ static void pl061_class_init(ObjectClass *klass, void *data)
 
     k->init = pl061_init_arm;
     dc->vmsd = &vmstate_pl061;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pl061_info = {
@@ -318,6 +319,7 @@ static void pl061_luminary_class_init(ObjectClass *klass, void *data)
 
     k->init = pl061_init_luminary;
     dc->vmsd = &vmstate_pl061;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pl061_luminary_info = {
diff --git a/hw/pl080.c b/hw/pl080.c
index f6bbf98..d6e52b2 100644
--- a/hw/pl080.c
+++ b/hw/pl080.c
@@ -384,6 +384,7 @@ static void pl080_class_init(ObjectClass *klass, void *data)
     k->init = pl080_init;
     dc->no_user = 1;
     dc->vmsd = &vmstate_pl080;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pl080_info = {
@@ -401,6 +402,7 @@ static void pl081_class_init(ObjectClass *klass, void *data)
     k->init = pl081_init;
     dc->no_user = 1;
     dc->vmsd = &vmstate_pl080;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pl081_info = {
diff --git a/hw/ppc/e500.c b/hw/ppc/e500.c
index 451682c..6a09671 100644
--- a/hw/ppc/e500.c
+++ b/hw/ppc/e500.c
@@ -684,6 +684,7 @@ static void e500_ccsr_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
     k->init = e500_ccsr_initfn;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo e500_ccsr_info = {
diff --git a/hw/ppce500_pci.c b/hw/ppce500_pci.c
index 1e1ade3..03f054a 100644
--- a/hw/ppce500_pci.c
+++ b/hw/ppce500_pci.c
@@ -387,6 +387,7 @@ static void e500_host_bridge_class_init(ObjectClass *klass, void *data)
     k->device_id = PCI_DEVICE_ID_MPC8533E;
     k->class_id = PCI_CLASS_PROCESSOR_POWERPC;
     dc->desc = "Host bridge";
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo e500_host_bridge_info = {
diff --git a/hw/ppce500_spin.c b/hw/ppce500_spin.c
index 5bdce52..5b4e027 100644
--- a/hw/ppce500_spin.c
+++ b/hw/ppce500_spin.c
@@ -205,6 +205,7 @@ static void ppce500_spin_class_init(ObjectClass *klass, void *data)
     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
 
     k->init = ppce500_spin_initfn;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo ppce500_spin_info = {
diff --git a/hw/puv3_dma.c b/hw/puv3_dma.c
index 9de63b4..f3731c5 100644
--- a/hw/puv3_dma.c
+++ b/hw/puv3_dma.c
@@ -90,8 +90,10 @@ static int puv3_dma_init(SysBusDevice *dev)
 static void puv3_dma_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sdc->init = puv3_dma_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo puv3_dma_info = {
diff --git a/hw/puv3_gpio.c b/hw/puv3_gpio.c
index 152248d..2259259 100644
--- a/hw/puv3_gpio.c
+++ b/hw/puv3_gpio.c
@@ -122,8 +122,10 @@ static int puv3_gpio_init(SysBusDevice *dev)
 static void puv3_gpio_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sdc->init = puv3_gpio_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo puv3_gpio_info = {
diff --git a/hw/puv3_intc.c b/hw/puv3_intc.c
index 07f5649..c968ed1 100644
--- a/hw/puv3_intc.c
+++ b/hw/puv3_intc.c
@@ -116,8 +116,10 @@ static int puv3_intc_init(SysBusDevice *dev)
 static void puv3_intc_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sdc->init = puv3_intc_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo puv3_intc_info = {
diff --git a/hw/puv3_ost.c b/hw/puv3_ost.c
index 14c6f21..f5556d0 100644
--- a/hw/puv3_ost.c
+++ b/hw/puv3_ost.c
@@ -132,8 +132,10 @@ static int puv3_ost_init(SysBusDevice *dev)
 static void puv3_ost_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sdc->init = puv3_ost_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo puv3_ost_info = {
diff --git a/hw/puv3_pm.c b/hw/puv3_pm.c
index 87a687a..9a1bcd3 100644
--- a/hw/puv3_pm.c
+++ b/hw/puv3_pm.c
@@ -130,8 +130,10 @@ static int puv3_pm_init(SysBusDevice *dev)
 static void puv3_pm_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sdc->init = puv3_pm_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo puv3_pm_info = {
diff --git a/hw/pxa2xx.c b/hw/pxa2xx.c
index d303320..d6fe863 100644
--- a/hw/pxa2xx.c
+++ b/hw/pxa2xx.c
@@ -1192,6 +1192,7 @@ static void pxa2xx_rtc_sysbus_class_init(ObjectClass *klass, void *data)
     k->init = pxa2xx_rtc_init;
     dc->desc = "PXA2xx RTC Controller";
     dc->vmsd = &vmstate_pxa2xx_rtc_regs;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pxa2xx_rtc_sysbus_info = {
@@ -1508,6 +1509,7 @@ static void pxa2xx_i2c_class_init(ObjectClass *klass, void *data)
     dc->desc = "PXA2xx I2C Bus Controller";
     dc->vmsd = &vmstate_pxa2xx_i2c;
     dc->props = pxa2xx_i2c_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pxa2xx_i2c_info = {
@@ -2269,8 +2271,10 @@ PXA2xxState *pxa255_init(MemoryRegion *address_space, unsigned int sdram_size)
 static void pxa2xx_ssp_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sdc->init = pxa2xx_ssp_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pxa2xx_ssp_info = {
diff --git a/hw/pxa2xx_dma.c b/hw/pxa2xx_dma.c
index c0dba45..8df1cdc 100644
--- a/hw/pxa2xx_dma.c
+++ b/hw/pxa2xx_dma.c
@@ -557,6 +557,7 @@ static void pxa2xx_dma_class_init(ObjectClass *klass, void *data)
     dc->desc = "PXA2xx DMA controller";
     dc->vmsd = &vmstate_pxa2xx_dma;
     dc->props = pxa2xx_dma_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pxa2xx_dma_info = {
diff --git a/hw/pxa2xx_gpio.c b/hw/pxa2xx_gpio.c
index 05d2ad2..81bbf47 100644
--- a/hw/pxa2xx_gpio.c
+++ b/hw/pxa2xx_gpio.c
@@ -333,6 +333,7 @@ static void pxa2xx_gpio_class_init(ObjectClass *klass, void *data)
     k->init = pxa2xx_gpio_initfn;
     dc->desc = "PXA2xx GPIO controller";
     dc->props = pxa2xx_gpio_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pxa2xx_gpio_info = {
diff --git a/hw/pxa2xx_pic.c b/hw/pxa2xx_pic.c
index 90b8fef..e576b93 100644
--- a/hw/pxa2xx_pic.c
+++ b/hw/pxa2xx_pic.c
@@ -317,6 +317,7 @@ static void pxa2xx_pic_class_init(ObjectClass *klass, void *data)
     k->init = pxa2xx_pic_initfn;
     dc->desc = "PXA2xx PIC";
     dc->vmsd = &vmstate_pxa2xx_pic_regs;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pxa2xx_pic_info = {
diff --git a/hw/pxa2xx_timer.c b/hw/pxa2xx_timer.c
index 5c9d2e8..c21f185 100644
--- a/hw/pxa2xx_timer.c
+++ b/hw/pxa2xx_timer.c
@@ -540,6 +540,7 @@ static void pxa25x_timer_dev_class_init(ObjectClass *klass, void *data)
     dc->desc = "PXA25x timer";
     dc->vmsd = &vmstate_pxa2xx_timer_regs;
     dc->props = pxa25x_timer_dev_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pxa25x_timer_dev_info = {
@@ -565,6 +566,7 @@ static void pxa27x_timer_dev_class_init(ObjectClass *klass, void *data)
     dc->desc = "PXA27x timer";
     dc->vmsd = &vmstate_pxa2xx_timer_regs;
     dc->props = pxa27x_timer_dev_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pxa27x_timer_dev_info = {
diff --git a/hw/realview_gic.c b/hw/realview_gic.c
index 8f2a7e2..0f2b4f1 100644
--- a/hw/realview_gic.c
+++ b/hw/realview_gic.c
@@ -55,8 +55,10 @@ static int realview_gic_init(SysBusDevice *dev)
 static void realview_gic_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sdc->init = realview_gic_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo realview_gic_info = {
diff --git a/hw/sdhci.c b/hw/sdhci.c
index e535df9..abcb3ae 100644
--- a/hw/sdhci.c
+++ b/hw/sdhci.c
@@ -1265,6 +1265,7 @@ static void sdhci_class_init(ObjectClass *klass, void *data)
     dc->props = sdhci_properties;
     dc->reset = sdhci_generic_reset;
     dc->realize = sdhci_realize;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 
     k->reset = sdhci_reset;
     k->mem_read = sdhci_read;
diff --git a/hw/sh_pci.c b/hw/sh_pci.c
index 077d957..60b21ed 100644
--- a/hw/sh_pci.c
+++ b/hw/sh_pci.c
@@ -166,8 +166,10 @@ static const TypeInfo sh_pci_host_info = {
 static void sh_pci_device_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sdc->init = sh_pci_device_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo sh_pci_device_info = {
diff --git a/hw/slavio_intctl.c b/hw/slavio_intctl.c
index 136ceeb..fdb4877 100644
--- a/hw/slavio_intctl.c
+++ b/hw/slavio_intctl.c
@@ -454,6 +454,7 @@ static void slavio_intctl_class_init(ObjectClass *klass, void *data)
     k->init = slavio_intctl_init1;
     dc->reset = slavio_intctl_reset;
     dc->vmsd = &vmstate_intctl;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo slavio_intctl_info = {
diff --git a/hw/slavio_misc.c b/hw/slavio_misc.c
index af24cc1..cf7cb9e 100644
--- a/hw/slavio_misc.c
+++ b/hw/slavio_misc.c
@@ -476,6 +476,7 @@ static void slavio_misc_class_init(ObjectClass *klass, void *data)
     k->init = slavio_misc_init1;
     dc->reset = slavio_misc_reset;
     dc->vmsd = &vmstate_misc;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo slavio_misc_info = {
@@ -488,8 +489,10 @@ static const TypeInfo slavio_misc_info = {
 static void apc_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(dc);
 
     k->init = apc_init1;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo apc_info = {
diff --git a/hw/slavio_timer.c b/hw/slavio_timer.c
index 68a4c0c..595d1f4 100644
--- a/hw/slavio_timer.c
+++ b/hw/slavio_timer.c
@@ -418,6 +418,7 @@ static void slavio_timer_class_init(ObjectClass *klass, void *data)
     dc->reset = slavio_timer_reset;
     dc->vmsd = &vmstate_slavio_timer;
     dc->props = slavio_timer_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo slavio_timer_info = {
diff --git a/hw/smc91c111.c b/hw/smc91c111.c
index 67fd074..0e4e2fc 100644
--- a/hw/smc91c111.c
+++ b/hw/smc91c111.c
@@ -773,6 +773,7 @@ static void smc91c111_class_init(ObjectClass *klass, void *data)
     dc->reset = smc91c111_reset;
     dc->vmsd = &vmstate_smc91c111;
     dc->props = smc91c111_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo smc91c111_info = {
diff --git a/hw/sparc32_dma.c b/hw/sparc32_dma.c
index 6d0df51..26f327d 100644
--- a/hw/sparc32_dma.c
+++ b/hw/sparc32_dma.c
@@ -298,6 +298,7 @@ static void sparc32_dma_class_init(ObjectClass *klass, void *data)
     dc->reset = dma_reset;
     dc->vmsd = &vmstate_dma;
     dc->props = sparc32_dma_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo sparc32_dma_info = {
diff --git a/hw/spitz.c b/hw/spitz.c
index 5bc49fc..d338bd6 100644
--- a/hw/spitz.c
+++ b/hw/spitz.c
@@ -1024,6 +1024,7 @@ static void sl_nand_class_init(ObjectClass *klass, void *data)
     k->init = sl_nand_init;
     dc->vmsd = &vmstate_sl_nand_info;
     dc->props = sl_nand_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo sl_nand_info = {
@@ -1059,6 +1060,7 @@ static void spitz_keyboard_class_init(ObjectClass *klass, void *data)
     k->init = spitz_keyboard_init;
     dc->vmsd = &vmstate_spitz_kbd;
     dc->props = spitz_keyboard_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo spitz_keyboard_info = {
@@ -1088,6 +1090,7 @@ static void corgi_ssp_class_init(ObjectClass *klass, void *data)
     k->init = corgi_ssp_init;
     k->transfer = corgi_ssp_transfer;
     dc->vmsd = &vmstate_corgi_ssp_regs;
+    dc->no_user = 1; /* for gpio */
 }
 
 static const TypeInfo corgi_ssp_info = {
diff --git a/hw/stellaris.c b/hw/stellaris.c
index 9b8f203..0786922 100644
--- a/hw/stellaris.c
+++ b/hw/stellaris.c
@@ -1352,8 +1352,10 @@ machine_init(stellaris_machine_init);
 static void stellaris_i2c_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sdc->init = stellaris_i2c_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo stellaris_i2c_info = {
@@ -1366,8 +1368,10 @@ static const TypeInfo stellaris_i2c_info = {
 static void stellaris_gptm_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sdc->init = stellaris_gptm_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo stellaris_gptm_info = {
@@ -1380,8 +1384,10 @@ static const TypeInfo stellaris_gptm_info = {
 static void stellaris_adc_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sdc->init = stellaris_adc_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo stellaris_adc_info = {
diff --git a/hw/stellaris_enet.c b/hw/stellaris_enet.c
index 6c701fb..270862e 100644
--- a/hw/stellaris_enet.c
+++ b/hw/stellaris_enet.c
@@ -433,6 +433,7 @@ static void stellaris_enet_class_init(ObjectClass *klass, void *data)
 
     k->init = stellaris_enet_init;
     dc->props = stellaris_enet_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo stellaris_enet_info = {
diff --git a/hw/strongarm.c b/hw/strongarm.c
index ab736e3..ab61dec 100644
--- a/hw/strongarm.c
+++ b/hw/strongarm.c
@@ -210,6 +210,7 @@ static void strongarm_pic_class_init(ObjectClass *klass, void *data)
     k->init = strongarm_pic_initfn;
     dc->desc = "StrongARM PIC";
     dc->vmsd = &vmstate_strongarm_pic_regs;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo strongarm_pic_info = {
@@ -431,6 +432,7 @@ static void strongarm_rtc_sysbus_class_init(ObjectClass *klass, void *data)
     k->init = strongarm_rtc_init;
     dc->desc = "StrongARM RTC Controller";
     dc->vmsd = &vmstate_strongarm_rtc_regs;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo strongarm_rtc_sysbus_info = {
@@ -672,6 +674,7 @@ static void strongarm_gpio_class_init(ObjectClass *klass, void *data)
 
     k->init = strongarm_gpio_initfn;
     dc->desc = "StrongARM GPIO controller";
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo strongarm_gpio_info = {
@@ -838,6 +841,7 @@ static void strongarm_ppc_class_init(ObjectClass *klass, void *data)
 
     k->init = strongarm_ppc_init;
     dc->desc = "StrongARM PPC controller";
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo strongarm_ppc_info = {
@@ -1297,6 +1301,7 @@ static void strongarm_uart_class_init(ObjectClass *klass, void *data)
     dc->reset = strongarm_uart_reset;
     dc->vmsd = &vmstate_strongarm_uart_regs;
     dc->props = strongarm_uart_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo strongarm_uart_info = {
diff --git a/hw/sun4m.c b/hw/sun4m.c
index 9903f44..89dc058 100644
--- a/hw/sun4m.c
+++ b/hw/sun4m.c
@@ -629,8 +629,10 @@ static int idreg_init1(SysBusDevice *dev)
 static void idreg_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     k->init = idreg_init1;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo idreg_info = {
@@ -671,8 +673,10 @@ static int afx_init1(SysBusDevice *dev)
 static void afx_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     k->init = afx_init1;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo afx_info = {
@@ -750,6 +754,7 @@ static void prom_class_init(ObjectClass *klass, void *data)
 
     k->init = prom_init1;
     dc->props = prom_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo prom_info = {
@@ -814,6 +819,7 @@ static void ram_class_init(ObjectClass *klass, void *data)
 
     k->init = ram_init1;
     dc->props = ram_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo ram_info = {
diff --git a/hw/sun4m_iommu.c b/hw/sun4m_iommu.c
index 8f9635f..8cbfeb9 100644
--- a/hw/sun4m_iommu.c
+++ b/hw/sun4m_iommu.c
@@ -371,6 +371,7 @@ static void iommu_class_init(ObjectClass *klass, void *data)
     dc->reset = iommu_reset;
     dc->vmsd = &vmstate_iommu;
     dc->props = iommu_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo iommu_info = {
diff --git a/hw/tcx.c b/hw/tcx.c
index 0ce2952..38681b5 100644
--- a/hw/tcx.c
+++ b/hw/tcx.c
@@ -714,6 +714,7 @@ static void tcx_class_init(ObjectClass *klass, void *data)
     dc->reset = tcx_reset;
     dc->vmsd = &vmstate_tcx;
     dc->props = tcx_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo tcx_info = {
diff --git a/hw/tusb6010.c b/hw/tusb6010.c
index 2c7d033..ac2357c 100644
--- a/hw/tusb6010.c
+++ b/hw/tusb6010.c
@@ -796,6 +796,7 @@ static void tusb6010_class_init(ObjectClass *klass, void *data)
 
     k->init = tusb6010_init;
     dc->reset = tusb6010_reset;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo tusb6010_info = {
diff --git a/hw/usb/hcd-ehci-sysbus.c b/hw/usb/hcd-ehci-sysbus.c
index b68a66a..28f6070 100644
--- a/hw/usb/hcd-ehci-sysbus.c
+++ b/hw/usb/hcd-ehci-sysbus.c
@@ -56,6 +56,7 @@ static void ehci_sysbus_class_init(ObjectClass *klass, void *data)
     k->init = usb_ehci_sysbus_initfn;
     dc->vmsd = &vmstate_ehci_sysbus;
     dc->props = ehci_sysbus_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo ehci_type_info = {
diff --git a/hw/usb/hcd-ohci.c b/hw/usb/hcd-ohci.c
index 51241cd..2408e9e 100644
--- a/hw/usb/hcd-ohci.c
+++ b/hw/usb/hcd-ohci.c
@@ -1931,6 +1931,7 @@ static void ohci_sysbus_class_init(ObjectClass *klass, void *data)
     sbc->init = ohci_init_pxa;
     dc->desc = "OHCI USB Controller";
     dc->props = ohci_sysbus_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo ohci_sysbus_info = {
diff --git a/hw/versatile_i2c.c b/hw/versatile_i2c.c
index ad71e9d..a5bbb42 100644
--- a/hw/versatile_i2c.c
+++ b/hw/versatile_i2c.c
@@ -88,8 +88,10 @@ static int versatile_i2c_init(SysBusDevice *dev)
 static void versatile_i2c_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     k->init = versatile_i2c_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo versatile_i2c_info = {
diff --git a/hw/versatile_pci.c b/hw/versatile_pci.c
index 9d99159..68a4f1a 100644
--- a/hw/versatile_pci.c
+++ b/hw/versatile_pci.c
@@ -143,8 +143,10 @@ static const TypeInfo pci_vpb_info = {
 static void pci_realview_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sdc->init = pci_realview_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo pci_realview_info = {
diff --git a/hw/xgmac.c b/hw/xgmac.c
index 5072298..36c53de 100644
--- a/hw/xgmac.c
+++ b/hw/xgmac.c
@@ -416,6 +416,7 @@ static void xgmac_enet_class_init(ObjectClass *klass, void *data)
     sbc->init = xgmac_enet_init;
     dc->vmsd = &vmstate_xgmac;
     dc->props = xgmac_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo xgmac_enet_info = {
diff --git a/hw/xilinx_axidma.c b/hw/xilinx_axidma.c
index cc51584..35c7776 100644
--- a/hw/xilinx_axidma.c
+++ b/hw/xilinx_axidma.c
@@ -500,6 +500,7 @@ static void axidma_class_init(ObjectClass *klass, void *data)
 
     k->init = xilinx_axidma_init;
     dc->props = axidma_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
     ssc->push = axidma_push;
 }
 
diff --git a/hw/xilinx_axienet.c b/hw/xilinx_axienet.c
index e5d9251..862ad08 100644
--- a/hw/xilinx_axienet.c
+++ b/hw/xilinx_axienet.c
@@ -892,6 +892,7 @@ static void xilinx_enet_class_init(ObjectClass *klass, void *data)
 
     k->init = xilinx_enet_init;
     dc->props = xilinx_enet_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
     ssc->push = axienet_stream_push;
 }
 
diff --git a/hw/xilinx_ethlite.c b/hw/xilinx_ethlite.c
index 21c6f8c..d987d66 100644
--- a/hw/xilinx_ethlite.c
+++ b/hw/xilinx_ethlite.c
@@ -246,6 +246,7 @@ static void xilinx_ethlite_class_init(ObjectClass *klass, void *data)
 
     k->init = xilinx_ethlite_init;
     dc->props = xilinx_ethlite_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo xilinx_ethlite_info = {
diff --git a/hw/xilinx_intc.c b/hw/xilinx_intc.c
index 0c34149..9b8caad 100644
--- a/hw/xilinx_intc.c
+++ b/hw/xilinx_intc.c
@@ -173,6 +173,7 @@ static void xilinx_intc_class_init(ObjectClass *klass, void *data)
 
     k->init = xilinx_intc_init;
     dc->props = xilinx_intc_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo xilinx_intc_info = {
diff --git a/hw/xilinx_spi.c b/hw/xilinx_spi.c
index be581c2..785e858 100644
--- a/hw/xilinx_spi.c
+++ b/hw/xilinx_spi.c
@@ -368,6 +368,7 @@ static void xilinx_spi_class_init(ObjectClass *klass, void *data)
     dc->reset = xlx_spi_reset;
     dc->props = xilinx_spi_properties;
     dc->vmsd = &vmstate_xilinx_spi;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo xilinx_spi_info = {
diff --git a/hw/xilinx_spips.c b/hw/xilinx_spips.c
index 42e019d..91c496a 100644
--- a/hw/xilinx_spips.c
+++ b/hw/xilinx_spips.c
@@ -558,6 +558,7 @@ static void xilinx_spips_class_init(ObjectClass *klass, void *data)
     dc->reset = xilinx_spips_reset;
     dc->props = xilinx_spips_properties;
     dc->vmsd = &vmstate_xilinx_spips;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo xilinx_spips_info = {
diff --git a/hw/xilinx_timer.c b/hw/xilinx_timer.c
index aa162ef..3b614a6 100644
--- a/hw/xilinx_timer.c
+++ b/hw/xilinx_timer.c
@@ -238,6 +238,7 @@ static void xilinx_timer_class_init(ObjectClass *klass, void *data)
 
     k->init = xilinx_timer_init;
     dc->props = xilinx_timer_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo xilinx_timer_info = {
diff --git a/hw/xilinx_uartlite.c b/hw/xilinx_uartlite.c
index 9963982..e55212a 100644
--- a/hw/xilinx_uartlite.c
+++ b/hw/xilinx_uartlite.c
@@ -212,8 +212,10 @@ static int xilinx_uartlite_init(SysBusDevice *dev)
 static void xilinx_uartlite_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sdc->init = xilinx_uartlite_init;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo xilinx_uartlite_info = {
diff --git a/hw/zaurus.c b/hw/zaurus.c
index 2defe3b..b53f4c4 100644
--- a/hw/zaurus.c
+++ b/hw/zaurus.c
@@ -234,6 +234,7 @@ static void scoop_sysbus_class_init(ObjectClass *klass, void *data)
     dc->desc = "Scoop2 Sharp custom ASIC";
     dc->vmsd = &vmstate_scoop_regs;
     dc->props = scoop_sysbus_properties;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo scoop_sysbus_info = {
diff --git a/hw/zynq_slcr.c b/hw/zynq_slcr.c
index 27b00f0..7b80c48 100644
--- a/hw/zynq_slcr.c
+++ b/hw/zynq_slcr.c
@@ -519,6 +519,7 @@ static void zynq_slcr_class_init(ObjectClass *klass, void *data)
     sdc->init = zynq_slcr_init;
     dc->vmsd = &vmstate_zynq_slcr;
     dc->reset = zynq_slcr_reset;
+    dc->no_user = 1; /* for sysbus mmio/irq */
 }
 
 static const TypeInfo zynq_slcr_info = {
