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Tsirkin" Cc: Si-Wei Liu , linux-kernel@vger.kernel.org, Dragos Tatulea , virtualization@lists.linux-foundation.org, leiyang@redhat.com, Xuan Zhuo , Jason Wang Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H3,RCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Wed, 04 Oct 2023 05:58:26 -0700 (PDT) On Tue, Jul 4, 2023 at 12:16=E2=80=AFPM Michael S. Tsirkin = wrote: > > On Mon, Jul 03, 2023 at 05:26:02PM -0700, Si-Wei Liu wrote: > > > > > > On 7/3/2023 8:46 AM, Michael S. Tsirkin wrote: > > > On Mon, Jul 03, 2023 at 04:25:14PM +0200, Eugenio P=C3=A9rez wrote: > > > > Offer this backend feature as mlx5 is compatible with it. It allows= it > > > > to do live migration with CVQ, dynamically switching between passth= rough > > > > and shadow virtqueue. > > > > > > > > Signed-off-by: Eugenio P=C3=A9rez > > > Same comment. > > to which? > > > > -Siwei > > VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK is too narrow a use-case to commit= to it > as a kernel/userspace ABI: what if one wants to start rings in some > other specific order? > As was discussed on list, a better promise is not to access ring > until the 1st kick. vdpa can then do a kick when it wants > the device to start accessing rings. > Friendly ping about this series, Now that VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK has been merged for vdpa_sim, does it make sense for mlx too? Thanks! > > > > > > > --- > > > > drivers/vdpa/mlx5/net/mlx5_vnet.c | 7 +++++++ > > > > 1 file changed, 7 insertions(+) > > > > > > > > diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/= net/mlx5_vnet.c > > > > index 9138ef2fb2c8..5f309a16b9dc 100644 > > > > --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c > > > > +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c > > > > @@ -7,6 +7,7 @@ > > > > #include > > > > #include > > > > #include > > > > +#include > > > > #include > > > > #include > > > > #include > > > > @@ -2499,6 +2500,11 @@ static void unregister_link_notifier(struct = mlx5_vdpa_net *ndev) > > > > flush_workqueue(ndev->mvdev.wq); > > > > } > > > > +static u64 mlx5_vdpa_get_backend_features(const struct vdpa_device= *vdpa) > > > > +{ > > > > + return BIT_ULL(VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK); > > > > +} > > > > + > > > > static int mlx5_vdpa_set_driver_features(struct vdpa_device *vdev= , u64 features) > > > > { > > > > struct mlx5_vdpa_dev *mvdev =3D to_mvdev(vdev); > > > > @@ -3140,6 +3146,7 @@ static const struct vdpa_config_ops mlx5_vdpa= _ops =3D { > > > > .get_vq_align =3D mlx5_vdpa_get_vq_align, > > > > .get_vq_group =3D mlx5_vdpa_get_vq_group, > > > > .get_device_features =3D mlx5_vdpa_get_device_features, > > > > + .get_backend_features =3D mlx5_vdpa_get_backend_features, > > > > .set_driver_features =3D mlx5_vdpa_set_driver_features, > > > > .get_driver_features =3D mlx5_vdpa_get_driver_features, > > > > .set_config_cb =3D mlx5_vdpa_set_config_cb, > > > > -- > > > > 2.39.3 >