Re: [PATCH net v2 2/3] i40e: add double of VLAN header when computing the max MTU

From: Alexander H Duyck
Date: Wed Feb 08 2023 - 10:41:23 EST


On Wed, 2023-02-08 at 10:43 +0800, Jason Xing wrote:
> From: Jason Xing <kernelxing@xxxxxxxxxxx>
>
> Include the second VLAN HLEN into account when computing the maximum
> MTU size as other drivers do.
>
> Fixes: 0c8493d90b6b ("i40e: add XDP support for pass and drop actions")
> Signed-off-by: Jason Xing <kernelxing@xxxxxxxxxxx>
> ---
> v2: drop the duplicate definition
> ---
> drivers/net/ethernet/intel/i40e/i40e_main.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
> index 53d0083e35da..d039928f3646 100644
> --- a/drivers/net/ethernet/intel/i40e/i40e_main.c
> +++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
> @@ -2921,7 +2921,7 @@ static int i40e_change_mtu(struct net_device *netdev, int new_mtu)
> struct i40e_pf *pf = vsi->back;
>
> if (i40e_enabled_xdp_vsi(vsi)) {
> - int frame_size = new_mtu + ETH_HLEN + ETH_FCS_LEN + VLAN_HLEN;
> + int frame_size = new_mtu + I40E_PACKET_HDR_PAD;
>
> if (frame_size > i40e_max_xdp_frame_size(vsi))
> return -EINVAL;

Looks good to me.

Reviewed-by: Alexander Duyck <alexanderduyck@xxxxxx>