On Wed, Jun 7, 2023 at 11:09 AM Zhu Lingshan <lingshan....@intel.com> wrote: > > When read the state of a virtqueue, vhost_vdpa need > to check whether the device is suspended. > > This commit verifies whether VHOST_BACKEND_F_SUSPEND is > negotiated when checking vhost_vdpa->suspended. >
I'll add: Otherwise, qemu prints XXX error message. On second thought, not returning an error prevents the caller (vhost.c:vhost_virtqueue_stop) from recovering used idx from the guest. I'm not sure about the right fix for this, should we call virtio_queue_restore_last_avail_idx here? Communicate that the backend cannot suspend so vhost.c can print a better error message? Thanks! > Signed-off-by: Zhu Lingshan <lingshan....@intel.com> > --- > hw/virtio/vhost-vdpa.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c > index b3094e8a8b..ae176c06dd 100644 > --- a/hw/virtio/vhost-vdpa.c > +++ b/hw/virtio/vhost-vdpa.c > @@ -1397,7 +1397,7 @@ static int vhost_vdpa_get_vring_base(struct vhost_dev > *dev, > return 0; > } > > - if (!v->suspended) { > + if ((dev->backend_cap & BIT_ULL(VHOST_BACKEND_F_SUSPEND)) && > (!v->suspended)) { > /* > * Cannot trust in value returned by device, let vhost recover used > * idx from guest. > -- > 2.39.1 >