diff --git a/hw/display/ati.c b/hw/display/ati.c
index 67604e68de..1d9df92b96 100644
--- a/hw/display/ati.c
+++ b/hw/display/ati.c
@@ -935,6 +935,8 @@ static void ati_vga_realize(PCIDevice *dev, Error **errp)
     bitbang_i2c_init(&s->bbi2c, i2cbus);
     I2CSlave *i2cddc = I2C_SLAVE(qdev_create(BUS(i2cbus), TYPE_I2CDDC));
     i2c_set_slave_address(i2cddc, 0x50);
+    object_property_set_bool(OBJECT(i2cddc), true, "realized",
+                             &error_abort);
 
     /* mmio register space */
     memory_region_init_io(&s->mm, OBJECT(s), &ati_mm_ops, s,
diff --git a/hw/display/sm501.c b/hw/display/sm501.c
index edd8d24a76..fa23a78164 100644
--- a/hw/display/sm501.c
+++ b/hw/display/sm501.c
@@ -1833,6 +1833,8 @@ static void sm501_init(SM501State *s, DeviceState *dev,
     /* ddc */
     I2CDDCState *ddc = I2CDDC(qdev_create(BUS(s->i2c_bus), TYPE_I2CDDC));
     i2c_set_slave_address(I2C_SLAVE(ddc), 0x50);
+    object_property_set_bool(OBJECT(ddc), true, "realized",
+                             &error_abort);
 
     /* mmio */
     memory_region_init(&s->mmio_region, OBJECT(dev), "sm501.mmio", MMIO_SIZE);