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Date: Fri, 11 May 2012 08:42:44 +0200
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] qom: fix refcounting in
	object_property_del_child()
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To: Amos Kong <akong@redhat.com>
Cc: aliguori@us.ibm.com, qemu-devel@nongnu.org

Il 11/05/2012 04:15, Amos Kong ha scritto:
> Start VM with 8 multiple-function block devs, hot-removing
> those block devs by 'device_del ...' would cause qemu abort.
> 
> object_ref() is called in object_property_add_child(),
> but we don't unref it in object_property_del_child().
> 
> | (qemu) device_del virti0-0-0
> | (qemu) **
> | ERROR:qom/object.c:389:object_delete: assertion failed: (obj->ref == 0)
> 
> Signed-off-by: Amos Kong <akong@redhat.com>
> ---
>  qom/object.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/qom/object.c b/qom/object.c
> index e721fc2..9da6b59 100644
> --- a/qom/object.c
> +++ b/qom/object.c
> @@ -320,6 +320,7 @@ static void object_property_del_child(Object *obj, Object *child, Error **errp)
>      QTAILQ_FOREACH(prop, &obj->properties, node) {
>          if (strstart(prop->type, "child<", NULL) && prop->opaque == child) {
>              object_property_del(obj, prop->name, errp);
> +            object_unref(child);

This should be called by object_finalize_child_property instead, can you
check why this is not the case?

Paolo

>              break;
>          }
>      }
>