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

Jason Xing
2023-02-08T02:03:59Z

On Wed, Feb 8, 2023 at 3:03 AM Tony Nguyen <anthony.l.nguyen@intel.com> wrote:
>
>
>
> On 2/4/2023 5:35 AM, Jason Xing wrote:
> > From: Jason Xing <kernelxing@tencent.com>
> >
> > 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@tencent.com>
> > ---
> > drivers/net/ethernet/intel/i40e/i40e.h | 2 ++
> > drivers/net/ethernet/intel/i40e/i40e_main.c | 2 +-
> > 2 files changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
> > index 60e351665c70..e03853d3c706 100644
> > --- a/drivers/net/ethernet/intel/i40e/i40e.h
> > +++ b/drivers/net/ethernet/intel/i40e/i40e.h
> > @@ -107,6 +107,8 @@
> > #define I40E_BW_MBPS_DIVISOR 125000 /* rate / (1000000 / 8) Mbps */
> > #define I40E_MAX_BW_INACTIVE_ACCUM 4 /* accumulate 4 credits max */
> >
> > +#define I40E_PACKET_HDR_PAD (ETH_HLEN + ETH_FCS_LEN + (VLAN_HLEN * 2))
>

> This already exists:
> https://elixir.bootlin.com/linux/latest/source/drivers/net/ethernet/intel/i40e/i40e_txrx.h#L112

Thanks for pointing out the duplication definition. I'll drop this in
the i40e.h file.