From 7addb3e4ad3db6a95a953c59884921b5883dcdec Mon Sep 17 00:00:00 2001 From: Emil Tantilov Date: Fri, 12 Jan 2018 14:02:56 -0800 Subject: [PATCH] ixgbe: don't set RXDCTL.RLPML for 82599 [ Upstream commit 2bafa8fac19a31ca72ae1a3e48df35f73661dbed ] commit 2de6aa3a666e ("ixgbe: Add support for padding packet") Uses RXDCTL.RLPML to limit the maximum frame size on Rx when using build_skb. Unfortunately that register does not work on 82599. Added an explicit check to avoid setting this register on 82599 MAC. Extended the comment related to the setting of RXDCTL.RLPML to better explain its purpose. Signed-off-by: Emil Tantilov Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c index 29f600fd6977..9e30cfeac04b 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c @@ -3987,11 +3987,15 @@ void ixgbe_configure_rx_ring(struct ixgbe_adapter *adapter, rxdctl &= ~0x3FFFFF; rxdctl |= 0x080420; #if (PAGE_SIZE < 8192) - } else { + /* RXDCTL.RLPML does not work on 82599 */ + } else if (hw->mac.type != ixgbe_mac_82599EB) { rxdctl &= ~(IXGBE_RXDCTL_RLPMLMASK | IXGBE_RXDCTL_RLPML_EN); - /* Limit the maximum frame size so we don't overrun the skb */ + /* Limit the maximum frame size so we don't overrun the skb. + * This can happen in SRIOV mode when the MTU of the VF is + * higher than the MTU of the PF. + */ if (ring_uses_build_skb(ring) && !test_bit(__IXGBE_RX_3K_BUFFER, &ring->state)) rxdctl |= IXGBE_MAX_2K_FRAME_BUILD_SKB | -- 2.20.1