From 655309e944fd482e59850d55186571c1b2a91e55 Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Wed, 8 Feb 2012 07:50:35 +0000 Subject: [PATCH] ixgbe: cleanup logic in ixgbe_change_mtu This change is meant to just cleanup the logic in ixgbe_change_mtu since we are making it unnecessarily complex due to a workaround required for 82599 when SR-IOV is enabled. Signed-off-by: Alexander Duyck Tested-by: Stephen Ko Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 20 +++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c index e97ef4591ade..db1f17c3ed47 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c @@ -5544,20 +5544,24 @@ static void ixgbe_free_all_rx_resources(struct ixgbe_adapter *adapter) static int ixgbe_change_mtu(struct net_device *netdev, int new_mtu) { struct ixgbe_adapter *adapter = netdev_priv(netdev); - struct ixgbe_hw *hw = &adapter->hw; int max_frame = new_mtu + ETH_HLEN + ETH_FCS_LEN; /* MTU < 68 is an error and causes problems on some kernels */ - if (adapter->flags & IXGBE_FLAG_SRIOV_ENABLED && - hw->mac.type != ixgbe_mac_X540) { - if ((new_mtu < 68) || (max_frame > MAXIMUM_ETHERNET_VLAN_SIZE)) - return -EINVAL; - } else { - if ((new_mtu < 68) || (max_frame > IXGBE_MAX_JUMBO_FRAME_SIZE)) + if ((new_mtu < 68) || (max_frame > IXGBE_MAX_JUMBO_FRAME_SIZE)) + return -EINVAL; + + /* + * For 82599EB we cannot allow PF to change MTU greater than 1500 + * in SR-IOV mode as it may cause buffer overruns in guest VFs that + * don't allocate and chain buffers correctly. + */ + if ((adapter->flags & IXGBE_FLAG_SRIOV_ENABLED) && + (adapter->hw.mac.type == ixgbe_mac_82599EB) && + (max_frame > MAXIMUM_ETHERNET_VLAN_SIZE)) return -EINVAL; - } e_info(probe, "changing MTU from %d to %d\n", netdev->mtu, new_mtu); + /* must set new MTU before calling down or up */ netdev->mtu = new_mtu; -- 2.20.1