It is not a problem if the destination does not have VIRTIO_BALLOON_F_MUST_TELL_HOST. In that case, the guest will simply do useless virtqueue traffic, but the destination does not have a problem.
(In fact, it _is_ a problem if the destination has VIRTIO_BALLOON_F_MUST_TELL_HOST but the source does not. The feature bit should have been backwards! Luckily, our implementation is free from this problem). Signed-off-by: Paolo Bonzini <pbonz...@redhat.com> --- hw/virtio-balloon.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/hw/virtio-balloon.c b/hw/virtio-balloon.c index 0ade8b0..d10df2e 100644 --- a/hw/virtio-balloon.c +++ b/hw/virtio-balloon.c @@ -216,7 +216,7 @@ static int virtio_balloon_load(QEMUFile *f, void *opaque, int version_id) if (version_id != 1) return -EINVAL; - ret = virtio_load(&s->vdev, f, 0); + ret = virtio_load(&s->vdev, f, VIRTIO_BALLOON_F_MUST_TELL_HOST); if (ret) { return ret; } -- 1.7.7.6