virtio-balloon: fix virtio-balloon child refcount in transports

object_initialize() leaves the object with a refcount of 1.
object_property_add_child() adds its own reference which is dropped
again when the property is deleted.

The upshot of this is that we always have a refcount >= 1.  Upon hot
unplug the virtio-balloon child is not finalized!

Drop our reference after the child property has been added to the
parent.

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
(cherry picked from commit 91ba21208839643603e7f7fa5864723c3f371ebe)
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>

diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c
index de0764de481525993650db7fc702f60a40964c00..c074f64e920044a2e32ab2ad6985521dd77b0549 100644 (file)
--- a/hw/s390x/virtio-ccw.c
+++ b/hw/s390x/virtio-ccw.c
@@ -900,7 +900,7 @@ static void virtio_ccw_balloon_instance_init(Object *obj)
     VirtIOBalloonCcw *dev = VIRTIO_BALLOON_CCW(obj);
     object_initialize(&dev->vdev, sizeof(dev->vdev), TYPE_VIRTIO_BALLOON);
     object_property_add_child(obj, "virtio-backend", OBJECT(&dev->vdev), NULL);
-
+    object_unref(OBJECT(&dev->vdev));
     object_property_add(obj, "guest-stats", "guest statistics",
                         balloon_ccw_stats_get_all, NULL, NULL, dev, NULL);
 

diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index 685395548f4c6145ebb602eb7a70ab4e662e2d07..6a355e746b7bdc5c7aada4f87a5c43c378d735b6 100644 (file)
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -1327,7 +1327,7 @@ static void virtio_balloon_pci_instance_init(Object *obj)
     VirtIOBalloonPCI *dev = VIRTIO_BALLOON_PCI(obj);
     object_initialize(&dev->vdev, sizeof(dev->vdev), TYPE_VIRTIO_BALLOON);
     object_property_add_child(obj, "virtio-backend", OBJECT(&dev->vdev), NULL);
-
+    object_unref(OBJECT(&dev->vdev));
     object_property_add(obj, "guest-stats", "guest statistics",
                         balloon_pci_stats_get_all, NULL, NULL, dev,
                         NULL);