Re: [dpdk-dev] [PATCH] vhost: fix dequeue zero copy not work with virtio1

[Yuanhan Liu <yliu@fridaylinux.org>]

On Fri, Dec 15, 2017 at 10:33:41AM +0000, Loftus, Ciara wrote:
> > 
> > Hi Junjie,
> > 
> > On 12/13/2017 05:50 PM, Junjie Chen wrote:
> > > This fix dequeue zero copy can not work with Qemu
> > > version >= 2.7. Since from Qemu 2.7 virtio device
> > > use virtio-1 protocol, the zero copy code path
> > > forget to add offset to buffer address.
> > >
> > > Signed-off-by: Junjie Chen <junjie.j.chen@intel.com>
> > > ---
> > >   lib/librte_vhost/virtio_net.c | 3 ++-
> > >   1 file changed, 2 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
> > > index 6fee16e..79d80f7 100644
> > > --- a/lib/librte_vhost/virtio_net.c
> > > +++ b/lib/librte_vhost/virtio_net.c
> > > @@ -977,7 +977,8 @@ copy_desc_to_mbuf(struct virtio_net *dev, struct
> > vhost_virtqueue *vq,
> > >   					desc->addr + desc_offset,
> > cpy_len)))) {
> > >   			cur->data_len = cpy_len;
> > >   			cur->data_off = 0;
> > > -			cur->buf_addr = (void *)(uintptr_t)desc_addr;
> > > +			cur->buf_addr = (void *)(uintptr_t)(desc_addr
> > > +				+ desc_offset);
> > >   			cur->buf_iova = hpa;
> > >
> > >   			/*
> > >
> > 
> > Thanks for fixing this.
> > 
> > Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
> > 
> > Maxime
> 
> Thanks for the fix. Can this be considered for the stable branch?

Yes, I think so. Applied to dpdk-next-virtio, with

Fixes: b0a985d1f340 ("vhost: add dequeue zero copy")
Cc: stable@dpdk.org

Thanks.

	--yliu