On Wed, May 08, 2024 at 12:01 PM Jason Wang <jasow...@redhat.com> wrote: > > On Mon, Apr 22, 2024 at 9:41 AM Wafer <wa...@jaguarmicro.com> wrote: > > > > The virtio-1.3 specification > > <https://docs.oasis-open.org/virtio/virtio/v1.3/virtio-v1.3.html> writes: > > 2.8.6 Next Flag: Descriptor Chaining > > Buffer ID is included in the last descriptor in the list. > > > > If the feature (_F_INDIRECT_DESC) has been negotiated, install only > > one descriptor in the virtqueue. > > Therefor the buffer id should be obtained from the first descriptor. > > > > In descriptor chaining scenarios, the buffer id should be obtained > > from the last descriptor. > > > > Fixes: 86044b24e8 ("virtio: basic packed virtqueue support") > > > > Signed-off-by: Wafer <wa...@jaguarmicro.com> > > --- > > hw/virtio/virtio.c | 5 +++++ > > 1 file changed, 5 insertions(+) > > > > diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index > > 871674f9be..f65d4b4161 100644 > > --- a/hw/virtio/virtio.c > > +++ b/hw/virtio/virtio.c > > @@ -1739,6 +1739,11 @@ static void *virtqueue_packed_pop(VirtQueue > *vq, size_t sz) > > goto err_undo_map; > > } > > > > + if (desc_cache != &indirect_desc_cache) { > > + /* Buffer ID is included in the last descriptor in the list. */ > > + id = desc.id; > > + } > > It looks to me we can move this out of the loop. > > Others look good. > > Thanks >
Thank you for your suggestion, I'll move out. > > + > > rc = virtqueue_packed_read_next_desc(vq, &desc, desc_cache, max, > &i, > > desc_cache == > > &indirect_desc_cache); > > -- > > 2.27.0 > >