net/mlx4_core: Disable mlx4_QP_ATTACH calls from guests if the host uses flow steering

Guests kernels may not correctly detect if DMFS (device-enabled flow steering) is
activated by the host. If DMFS is activated, the master should return error to guests
which try to use the B0-steering flow calls (mlx4_QP_ATTACH).

Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c b/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c
index 083fb48dc3d7..2995687f1aee 100644
--- a/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c
+++ b/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c
@@ -2990,6 +2990,9 @@ int mlx4_QP_ATTACH_wrapper(struct mlx4_dev *dev, int slave,
         u8 steer_type_mask = 2;
         enum mlx4_steer_type type = (gid[7] & steer_type_mask) >> 1;
 
+        if (dev->caps.steering_mode != MLX4_STEERING_MODE_B0)
+                return -EINVAL;
+
         qpn = vhcr->in_modifier & 0xffffff;
         err = get_res(dev, slave, qpn, RES_QP, &rqp);
         if (err)