On 07.11.24 22:50, Michael S. Tsirkin wrote: > On Wed, Sep 04, 2024 at 10:11:14AM -0500, Carlos Bilbao wrote: >> From: Carlos Bilbao <cbilbao@xxxxxxxxxxxxxxxx> >> >> Initialize the speed and duplex fields in virtio_net_config to UNKNOWN. >> This is needed because mlx5_vdpa vDPA devices currently do not support the >> VIRTIO_NET_F_SPEED_DUPLEX feature which reports speed and duplex. > > I see no logic here. Without this feature bit, guests will not read > this field, why do we suddenly need to initialize it? > IIRC, Carlos was reading data via ioctl VHOST_VDPA_GET_CONFIG which calls .get_config() directly, always exposing the speed and duplex config fields [0]. Carlos, was this the case? [0] https://lore.kernel.org/lkml/afcbf041-7613-48e6-8088-9d52edd907ff@xxxxxxxxxx/T/ Thanks, Dragos >> Add >> needed helper cpu_to_mlx5vdpa32() to convert endianness of speed. >> >> Signed-off-by: Carlos Bilbao <cbilbao@xxxxxxxxxxxxxxxx> >> Reviewed-by: Dragos Tatulea <dtatulea@xxxxxxxxxx> >> --- >> drivers/vdpa/mlx5/net/mlx5_vnet.c | 12 ++++++++++++ >> 1 file changed, 12 insertions(+) >> >> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c >> index b56aae3f7be3..41ca268d43ff 100644 >> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c >> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c >> @@ -173,6 +173,11 @@ static __virtio16 cpu_to_mlx5vdpa16(struct mlx5_vdpa_dev *mvdev, u16 val) >> return __cpu_to_virtio16(mlx5_vdpa_is_little_endian(mvdev), val); >> } >> >> +static __virtio32 cpu_to_mlx5vdpa32(struct mlx5_vdpa_dev *mvdev, u32 val) >> +{ >> + return __cpu_to_virtio32(mlx5_vdpa_is_little_endian(mvdev), val); >> +} >> + >> static u16 ctrl_vq_idx(struct mlx5_vdpa_dev *mvdev) >> { >> if (!(mvdev->actual_features & BIT_ULL(VIRTIO_NET_F_MQ))) >> @@ -3433,6 +3438,13 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name, >> init_rwsem(&ndev->reslock); >> config = &ndev->config; >> >> + /* >> + * mlx5_vdpa vDPA devices currently don't support reporting or >> + * setting the speed or duplex. >> + */ >> + config->speed = cpu_to_mlx5vdpa32(mvdev, SPEED_UNKNOWN); >> + config->duplex = DUPLEX_UNKNOWN; >> + >> if (add_config->mask & BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MTU)) { >> err = config_func_mtu(mdev, add_config->net.mtu); >> if (err) >> -- >> 2.34.1 >
