diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 6d15b36e0b..d7f02be595 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -1548,6 +1548,10 @@ bool vfio_attach_device(char *name, VFIODevice *vbasedev,
         return false;
     }
 
+    if (vbasedev->mdev) {
+        return true;
+    }
+
     hiod = HOST_IOMMU_DEVICE(object_new(ops->hiod_typename));
     if (!HOST_IOMMU_DEVICE_GET_CLASS(hiod)->realize(hiod, vbasedev, errp)) {
         object_unref(hiod);
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index b34e91468a..265d3cb82f 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -3115,7 +3115,8 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)
 
     vfio_bars_register(vdev);
 
-    if (!pci_device_set_iommu_device(pdev, vbasedev->hiod, errp)) {
+    if (!vbasedev->mdev &&
+        !pci_device_set_iommu_device(pdev, vbasedev->hiod, errp)) {
         error_prepend(errp, "Failed to set iommu_device: ");
         goto out_teardown;
     }
@@ -3238,7 +3239,9 @@ out_deregister:
         timer_free(vdev->intx.mmap_timer);
     }
 out_unset_idev:
-    pci_device_unset_iommu_device(pdev);
+    if (!vbasedev->mdev) {
+        pci_device_unset_iommu_device(pdev);
+    }
 out_teardown:
     vfio_teardown_msi(vdev);
     vfio_bars_exit(vdev);
@@ -3283,7 +3286,9 @@ static void vfio_exitfn(PCIDevice *pdev)
     vfio_pci_disable_rp_atomics(vdev);
     vfio_bars_exit(vdev);
     vfio_migration_exit(vbasedev);
-    pci_device_unset_iommu_device(pdev);
+    if (!vbasedev->mdev) {
+        pci_device_unset_iommu_device(pdev);
+    }
 }
 
 static void vfio_pci_reset(DeviceState *dev)