On Thu, 26 Jul 2018 10:40:45 -0700, Jeff Kirsher wrote:
> From: Tony Nguyen <anthony.l.ngu...@intel.com>
>
> XDP does not support jumbo frames or LRO. These checks are being made
> outside the driver when an XDP program is loaded, however, there is
> nothing preventing these from changing after an XDP program is loaded.
> Add the checks so that while an XDP program is loaded, do not allow MTU
> to be changed or LRO to be enabled.
>
> Signed-off-by: Tony Nguyen <anthony.l.ngu...@intel.com>
> Tested-by: Andrew Bowers <andrewx.bow...@intel.com>
> Signed-off-by: Jeff Kirsher <jeffrey.t.kirs...@intel.com>
> ---
> drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> index 5a6600f7b382..c42256e91997 100644
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> @@ -6469,6 +6469,11 @@ static int ixgbe_change_mtu(struct net_device *netdev,
> int new_mtu)
> {
> struct ixgbe_adapter *adapter = netdev_priv(netdev);
>
> + if (adapter->xdp_prog) {
> + e_warn(probe, "MTU cannot be changed while XDP program is
> loaded\n");
> + return -EPERM;
EPERM looks wrong, EINVAL is common. Also most drivers will just check
the bounds like you do in ixgbe_xdp_setup(), allowing the change if new
MTU still fits constraints.
FWIW are the IXGBE_FLAG_SRIOV_ENABLED and IXGBE_FLAG_DCB_ENABLED flag
changes also covered while xdp is enabled? Quick grep doesn't reveal
them being checked against xdp_prog other than in ixgbe_xdp_setup().
> + }
> +
> /*
> * For 82599EB we cannot allow legacy VFs to enable their receive
> * paths when MTU greater than 1500 is configured. So display a
> @@ -9407,6 +9412,11 @@ static netdev_features_t ixgbe_fix_features(struct
> net_device *netdev,
> if (!(adapter->flags2 & IXGBE_FLAG2_RSC_CAPABLE))
> features &= ~NETIF_F_LRO;
>
> + if (adapter->xdp_prog && (features & NETIF_F_LRO)) {
> + e_dev_err("LRO is not supported with XDP\n");
> + features &= ~NETIF_F_LRO;
> + }
> +
> return features;
> }
>
