diff mbox series

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

Message ID 20230204133535.99921-3-kerneljasonxing@gmail.com
State New
Headers
Series Fix MTU related issues |

Commit Message

Jason Xing Feb. 4, 2023, 1:35 p.m. UTC 
  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(-)

Comments

Tony Nguyen Feb. 7, 2023, 7:03 p.m. UTC | #1 
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
Jason Xing Feb. 8, 2023, 2:03 a.m. UTC | #2 
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.
diff mbox series

Patch

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))
+
 /* driver state flags */
 enum i40e_state_t {
 	__I40E_TESTING,
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;