On Fri, Jan 13, 2023 at 5:39 AM Jason Wang <jasow...@redhat.com> wrote: > > On Fri, Jan 13, 2023 at 1:25 AM Eugenio Pérez <epere...@redhat.com> wrote: > > > > This is needed for qemu to know it can suspend the device to retrieve > > its status and enable SVQ with it, so all the process is transparent to > > the guest. > > > > Signed-off-by: Eugenio Pérez <epere...@redhat.com> > > Acked-by: Jason Wang <jasow...@redhat.com> > > We probably need to add the resume in the future to have a quick > recovery from migration failures. >
The capability of a resume can be useful here but only in a small window. During the most time of the migration SVQ is enabled, so in the event of a migration failure we may need to reset the whole device to enable passthrough again. But maybe is it worth giving a quick review and adding some TODOs where it can be useful in this series? Thanks! > Thanks > > > --- > > hw/virtio/vhost-vdpa.c | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c > > index 4296427a69..a61a6b2a74 100644 > > --- a/hw/virtio/vhost-vdpa.c > > +++ b/hw/virtio/vhost-vdpa.c > > @@ -659,7 +659,8 @@ static int vhost_vdpa_set_backend_cap(struct vhost_dev > > *dev) > > uint64_t features; > > uint64_t f = 0x1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2 | > > 0x1ULL << VHOST_BACKEND_F_IOTLB_BATCH | > > - 0x1ULL << VHOST_BACKEND_F_IOTLB_ASID; > > + 0x1ULL << VHOST_BACKEND_F_IOTLB_ASID | > > + 0x1ULL << VHOST_BACKEND_F_SUSPEND; > > int r; > > > > if (vhost_vdpa_call(dev, VHOST_GET_BACKEND_FEATURES, &features)) { > > -- > > 2.31.1 > > >