Re: [Qemu-devel] [PULL 4/8] bus: do not unref the added child bus on realize

[Paolo Bonzini]

On 12/06/2018 12:44, Gerd Hoffmann wrote:
> 
> When the parent bus removes the child property, it takes care of
> removing the added reference, in object_finalize_child_property().
> 
> Signed-off-by: Marc-André Lureau <address@hidden>
> Message-id: address@hidden
> Signed-off-by: Gerd Hoffmann <address@hidden>
> ---
>  hw/core/bus.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/hw/core/bus.c b/hw/core/bus.c
> index 4651f24486..ad0c9df335 100644
> --- a/hw/core/bus.c
> +++ b/hw/core/bus.c
> @@ -102,7 +102,6 @@ static void qbus_realize(BusState *bus, DeviceState 
> *parent, const char *name)
>          QLIST_INSERT_HEAD(&bus->parent->child_bus, bus, sibling);
>          bus->parent->num_child_bus++;
>          object_property_add_child(OBJECT(bus->parent), bus->name, 
> OBJECT(bus), NULL);
> -        object_unref(OBJECT(bus));

This is wrong.  object_finalize_child_property()'s unref balances the
ref in object_property_add_child().  qbus_realize's unref balances the
ref that was initially placed by object_new/object_initialize.

So you're introducing a leak.

Paolo