[Qemu-devel] [PATCH 3/5] s390x: set missing parent for hotplug and quiesce events

[Jens Freimann <jfrei@linux.vnet.ibm.com>]

From: David Hildenbrand <dahi@linux.vnet.ibm.com>

Existing code missed to set a parent for the quiesce and hotplug event.
While this didn't matter in practise, new introspection APIs basically now
do an object_unref(object_new(T)), which loops forever.

When trying to remove the event facility bus, the code tries to
unparent all childs on the bus, so they are properly deleted and therefore removed.
As object_unparent() on these child devices doesn't work, as there is no parent,
we loop forever.

Let's fix this by adding the event facility as a parent. Also switch from
object_initialize to object_new, so the only valid reference is in fact the
parent property. This makes it more obvious when the device (state) is actually
gone (and how the reference counting works).

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
---
 hw/s390x/event-facility.c | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/hw/s390x/event-facility.c b/hw/s390x/event-facility.c
index ef2a051..907b485 100644
--- a/hw/s390x/event-facility.c
+++ b/hw/s390x/event-facility.c
@@ -27,8 +27,6 @@ typedef struct SCLPEventsBus {
 struct SCLPEventFacility {
     SysBusDevice parent_obj;
     SCLPEventsBus sbus;
-    SCLPEvent quiesce_event;
-    SCLPEvent cpu_hotplug_event;
     /* guest' receive mask */
     unsigned int receive_mask;
 };
@@ -347,19 +345,21 @@ static void init_event_facility(Object *obj)
 {
     SCLPEventFacility *event_facility = EVENT_FACILITY(obj);
     DeviceState *sdev = DEVICE(obj);
+    Object *new;
 
     /* Spawn a new bus for SCLP events */
     qbus_create_inplace(&event_facility->sbus, sizeof(event_facility->sbus),
                         TYPE_SCLP_EVENTS_BUS, sdev, NULL);
 
-    object_initialize(&event_facility->quiesce_event, sizeof(SCLPEvent),
-                      TYPE_SCLP_QUIESCE);
-    qdev_set_parent_bus(DEVICE(&event_facility->quiesce_event),
-                        &event_facility->sbus.qbus);
-    object_initialize(&event_facility->cpu_hotplug_event, sizeof(SCLPEvent),
-                      TYPE_SCLP_CPU_HOTPLUG);
-    qdev_set_parent_bus(DEVICE(&event_facility->cpu_hotplug_event),
-                        &event_facility->sbus.qbus);
+    new = object_new(TYPE_SCLP_QUIESCE);
+    object_property_add_child(obj, TYPE_SCLP_QUIESCE, new, NULL);
+    object_unref(new);
+    qdev_set_parent_bus(DEVICE(new), &event_facility->sbus.qbus);
+
+    new = object_new(TYPE_SCLP_CPU_HOTPLUG);
+    object_property_add_child(obj, TYPE_SCLP_CPU_HOTPLUG, new, NULL);
+    object_unref(new);
+    qdev_set_parent_bus(DEVICE(new), &event_facility->sbus.qbus);
     /* the facility will automatically realize the devices via the bus */
 }
 
-- 
2.3.9