Re: [Qemu-devel] [PATCH v3] balloon: Fix failure of updating guest memory status

[Ladi Prosek]

On Mon, Aug 15, 2016 at 2:09 PM, Stefan Hajnoczi <address@hidden> wrote:
> On Fri, Aug 05, 2016 at 01:36:32PM +0200, Ladi Prosek wrote:
>> diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c
>> index 5af429a..65457e9 100644
>> --- a/hw/virtio/virtio-balloon.c
>> +++ b/hw/virtio/virtio-balloon.c
>> @@ -423,6 +423,26 @@ static int virtio_balloon_load_device(VirtIODevice 
>> *vdev, QEMUFile *f,
>>      return 0;
>>  }
>>
>> +static void virtio_balloon_vmstate_cb(void *opaque, int running,
>> +                                      RunState state)
>> +{
>> +    VirtIOBalloon *s = opaque;
>> +
>> +    if (!running) {
>> +        /* put the stats element back if the VM is not running */
>> +        if (s->stats_vq_elem != NULL) {
>> +            virtqueue_discard(s->svq, s->stats_vq_elem, s->stats_vq_offset);
>
> The third argument should be 0 because we did not write anything into
> in_sg[].

Thanks! Then it looks like the regular virtqueue_push in
balloon_stats_poll_cb should also be called with 0 and the
stats_vq_offset field can be deleted altogether. We never write to
in_sg.

Ladi