This is a note to let you know that I've just added the patch titled ibmveth: Identify ingress large send packets. to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ibmveth-identify-ingress-large-send-packets.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Sat Oct 17 01:04:11 PM CEST 2020 From: David Wilder <dwilder@xxxxxxxxxx> Date: Tue, 13 Oct 2020 16:20:14 -0700 Subject: ibmveth: Identify ingress large send packets. From: David Wilder <dwilder@xxxxxxxxxx> [ Upstream commit 413f142cc05cb03f2d1ea83388e40c1ddc0d74e9 ] Ingress large send packets are identified by either: The IBMVETH_RXQ_LRG_PKT flag in the receive buffer or with a -1 placed in the ip header checksum. The method used depends on firmware version. Frame geometry and sufficient header validation is performed by the hypervisor eliminating the need for further header checks here. Fixes: 7b5967389f5a ("ibmveth: set correct gso_size and gso_type") Signed-off-by: David Wilder <dwilder@xxxxxxxxxx> Reviewed-by: Thomas Falcon <tlfalcon@xxxxxxxxxxxxx> Reviewed-by: Cristobal Forno <cris.forno@xxxxxxx> Reviewed-by: Pradeep Satyanarayana <pradeeps@xxxxxxxxxxxxxxxxxx> Acked-by: Willem de Bruijn <willemb@xxxxxxxxxx> Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/ibm/ibmveth.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) --- a/drivers/net/ethernet/ibm/ibmveth.c +++ b/drivers/net/ethernet/ibm/ibmveth.c @@ -1256,6 +1256,7 @@ static int ibmveth_poll(struct napi_stru int offset = ibmveth_rxq_frame_offset(adapter); int csum_good = ibmveth_rxq_csum_good(adapter); int lrg_pkt = ibmveth_rxq_large_packet(adapter); + __sum16 iph_check = 0; skb = ibmveth_rxq_get_buffer(adapter); @@ -1307,7 +1308,17 @@ static int ibmveth_poll(struct napi_stru } } - if (length > netdev->mtu + ETH_HLEN) { + /* PHYP without PLSO support places a -1 in the ip + * checksum for large send frames. + */ + if (skb->protocol == cpu_to_be16(ETH_P_IP)) { + struct iphdr *iph = (struct iphdr *)skb->data; + + iph_check = iph->check; + } + + if ((length > netdev->mtu + ETH_HLEN) || + lrg_pkt || iph_check == 0xffff) { ibmveth_rx_mss_helper(skb, mss, lrg_pkt); adapter->rx_large_packets++; } Patches currently in stable-queue which might be from dwilder@xxxxxxxxxx are queue-4.9/ibmveth-identify-ingress-large-send-packets.patch