Commit 0967bf83 authored by Jason Xing's avatar Jason Xing Committed by Tony Nguyen
Browse files

ixgbe: add double of VLAN header when computing the max MTU 



Include the second VLAN HLEN into account when computing the maximum
MTU size as other drivers do.

Fixes: fabf1bce ("ixgbe: Prevent unsupported configurations with XDP")
Signed-off-by: default avatarJason Xing <kernelxing@tencent.com>
Reviewed-by: default avatarAlexander Duyck <alexanderduyck@fb.com>
Tested-by: Chandan Kumar Rout <chandanx.rout@intel.com> (A Contingent Worker at Intel)
Signed-off-by: default avatarTony Nguyen <anthony.l.nguyen@intel.com>
parent ce45ffb8

drivers/net/ethernet/intel/ixgbe/ixgbe.h

+2 −0
Original line number Diff line number Diff line
@@ -73,6 +73,8 @@ 
#define IXGBE_RXBUFFER_4K    4096

#define IXGBE_MAX_RXBUFFER  16384  /* largest size for a single descriptor */



#define IXGBE_PKT_HDR_PAD   (ETH_HLEN + ETH_FCS_LEN + (VLAN_HLEN * 2))



/* Attempt to maximize the headroom available for incoming frames.  We

 * use a 2K buffer for receives and need 1536/1534 to store the data for

 * the frame.  This leaves us with 512 bytes of room.  From that we need

drivers/net/ethernet/intel/ixgbe/ixgbe_main.c

+1 −2
Original line number Diff line number Diff line
@@ -6801,8 +6801,7 @@ static int ixgbe_change_mtu(struct net_device *netdev, int new_mtu) 
	struct ixgbe_adapter *adapter = netdev_priv(netdev);



	if (ixgbe_enabled_xdp_adapter(adapter)) {

		int new_frame_size = new_mtu + ETH_HLEN + ETH_FCS_LEN +

				     VLAN_HLEN;

		int new_frame_size = new_mtu + IXGBE_PKT_HDR_PAD;



		if (new_frame_size > ixgbe_max_xdp_frame_size(adapter)) {

			e_warn(probe, "Requested MTU size is not supported with XDP\n");