Re: [Qemu-devel] [PATCH] ivshmem: fix memory backend leak

[Markus Armbruster]

Igor Mammedov <address@hidden> writes:

> On Thu, 1 Nov 2018 15:02:04 +0400
> Marc-André Lureau <address@hidden> wrote:
>
>> On Thu, Nov 1, 2018 at 2:53 PM Igor Mammedov <address@hidden> wrote:
>> >
>> > object_new() returns a new backend with refcount == 1 and
>> > then later object_property_add_child() increases refcount to 2
>> > So when ivshmem is desroyed, the backend it has created isn't
>> > destroyed along with it as children cleanup will bring
>> > backend's refcount only to 1, which leaks backend including
>> > resources it is using.
>> >
>> > Drop the original reference from object_new() once backend
>> > is attached to its parent.
>> >

I believe
Fixes: 5503e285041979dd29698ecb41729b3b22622e8d

>> > Signed-off-by: Igor Mammedov <address@hidden>  
>> 
>> I would rather have the unref in finalize, but that is ok too.
> I followed the pattern we use else where, i.e. drop reference
> as soon as we set the parent (virtio-rng/cpus) within the same
> scope as object_new().
>
> There is no point in keeping reference until finalize time since
> backend is kept alive as child and is destroyed well after all
> nonexistent ivshmem::unrealize/finilize() are finished when generic
> Object is being destroyed.

Concur.

>>  Reviewed-by: Marc-André Lureau <address@hidden>

With Philippe's spelling fix:
Reviewed-by: Markus Armbruster <address@hidden>