> >
> > dequeue zero copy change buf_addr and buf_iova of mbuf, and return to
> > mbuf pool without restore them, it breaks vm memory if others allocate
> > mbuf from same pool since mbuf reset doesn't reset buf_addr and
> buf_iova.
> >
> > Signed-off-by: Junjie Chen <junjie.j.c...@intel.com>
> > ---
> > lib/librte_vhost/virtio_net.c | 21 +++++++++++++++++++++
> > 1 file changed, 21 insertions(+)
> >
> > diff --git a/lib/librte_vhost/virtio_net.c
> > b/lib/librte_vhost/virtio_net.c index 568ad0e..e9aaf6d 100644
> > --- a/lib/librte_vhost/virtio_net.c
> > +++ b/lib/librte_vhost/virtio_net.c
> > @@ -1158,6 +1158,26 @@ mbuf_is_consumed(struct rte_mbuf *m)
> > return true;
> > }
> >
> > +
> > +static __rte_always_inline void
> > +restore_mbuf(struct rte_mbuf *m)
> > +{
> > + uint32_t mbuf_size, priv_size;
> > +
> > + while (m) {
> > + priv_size = rte_pktmbuf_priv_size(m->pool);
> > + mbuf_size = sizeof(struct rte_mbuf) + priv_size;
> > + /* start of buffer is after mbuf structure and priv data */
> > + m->priv_size = priv_size;
>
> I don't think we need to restore priv_size. Refer to its definition in
> rte_mbuf:
> "Size of the application private data. In case of an indirect mbuf, it
> stores the direct mbuf private data size."
>
> Thanks,
> Jianfeng
You are right, I also remove restore for data_len since it is reset when
allocating. Please see v2.
Thanks.
>
> > +
> > + m->buf_addr = (char *)m + mbuf_size;
> > + m->buf_iova = rte_mempool_virt2iova(m) + mbuf_size;
> > + m->data_off = RTE_MIN(RTE_PKTMBUF_HEADROOM,
> > + (uint16_t)m->buf_len);
> > + m = m->next;
> > + }
> > +}
> > +
> > uint16_t
> > rte_vhost_dequeue_burst(int vid, uint16_t queue_id,
> > struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint16_t
> > count)
> > @@ -1209,6 +1229,7 @@ rte_vhost_dequeue_burst(int vid, uint16_t
> > queue_id,
> > nr_updated += 1;
> >
> > TAILQ_REMOVE(&vq->zmbuf_list, zmbuf, next);
> > + restore_mbuf(zmbuf->mbuf);
> > rte_pktmbuf_free(zmbuf->mbuf);
> > put_zmbuf(zmbuf);
> > vq->nr_zmbuf -= 1;
> > --
> > 2.0.1
