From patchwork Tue Aug 17 08:06:59 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 499663 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B8818C4338F for ; Tue, 17 Aug 2021 08:07:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 95CD560F35 for ; Tue, 17 Aug 2021 08:07:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238885AbhHQIIE (ORCPT ); Tue, 17 Aug 2021 04:08:04 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:43986 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234693AbhHQIHv (ORCPT ); Tue, 17 Aug 2021 04:07:51 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1629187638; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=qVcE6UPf0wuZej4sXtxd/Uc1SmN5uwlN7K2SA3aUFHE=; b=cmxmFHSn4oX60oA/ngOIqp+/QcdSyqQ+YHItTLOfsDF1I+nFdRgg3Z4VWe/gxmsBQi/wrU VA4tFJtSoQhqvpNuy0ymVjdbu+/IFK+RjCPvK/HIslCEWl6zYwU8xJndzzF5viz2Aj/Dqw thH/UYeFMsSw8GJ5gGYE1vujBDYodIw= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-116-MGS0Ta-MPLayX6UyW_gr_Q-1; Tue, 17 Aug 2021 04:07:13 -0400 X-MC-Unique: MGS0Ta-MPLayX6UyW_gr_Q-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3CB731008065; Tue, 17 Aug 2021 08:07:12 +0000 (UTC) Received: from localhost.localdomain (ovpn-13-175.pek2.redhat.com [10.72.13.175]) by smtp.corp.redhat.com (Postfix) with ESMTP id 010405C1B4; Tue, 17 Aug 2021 08:07:04 +0000 (UTC) From: Jason Wang To: mst@redhat.com, jasowang@redhat.com Cc: davem@davemloft.net, kuba@kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, ivan@prestigetransportation.com, xiangxia.m.yue@gmail.com, willemb@google.com, edumazet@google.com Subject: [PATCH V2 net] virtio-net: use NETIF_F_GRO_HW instead of NETIF_F_LRO Date: Tue, 17 Aug 2021 16:06:59 +0800 Message-Id: <20210817080659.16223-1-jasowang@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Commit a02e8964eaf92 ("virtio-net: ethtool configurable LRO") maps LRO to virtio guest offloading features and allows the administrator to enable and disable those features via ethtool. This leads to several issues: - For a device that doesn't support control guest offloads, the "LRO" can't be disabled triggering WARN in dev_disable_lro() when turning off LRO or when enabling forwarding bridging etc. - For a device that supports control guest offloads, the guest offloads are disabled in cases of bridging, forwarding etc slowing down the traffic. Fix this by using NETIF_F_GRO_HW instead. Though the spec does not guarantee packets to be re-segmented as the original ones, we can add that to the spec, possibly with a flag for devices to differentiate between GRO and LRO. Further, we never advertised LRO historically before a02e8964eaf92 ("virtio-net: ethtool configurable LRO") and so bridged/forwarded configs effectively always relied on virtio receive offloads behaving like GRO - thus even if this breaks any configs it is at least not a regression. Fixes: a02e8964eaf92 ("virtio-net: ethtool configurable LRO") Acked-by: Michael S. Tsirkin Reported-by: Ivan Tested-by: Ivan Signed-off-by: Jason Wang --- Changes from V1: - Tweak the commit log --- drivers/net/virtio_net.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 0416a7e00914..10c382b08bce 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -63,7 +63,7 @@ static const unsigned long guest_offloads[] = { VIRTIO_NET_F_GUEST_CSUM }; -#define GUEST_OFFLOAD_LRO_MASK ((1ULL << VIRTIO_NET_F_GUEST_TSO4) | \ +#define GUEST_OFFLOAD_GRO_HW_MASK ((1ULL << VIRTIO_NET_F_GUEST_TSO4) | \ (1ULL << VIRTIO_NET_F_GUEST_TSO6) | \ (1ULL << VIRTIO_NET_F_GUEST_ECN) | \ (1ULL << VIRTIO_NET_F_GUEST_UFO)) @@ -2481,7 +2481,7 @@ static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog, virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) || virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO) || virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_CSUM))) { - NL_SET_ERR_MSG_MOD(extack, "Can't set XDP while host is implementing LRO/CSUM, disable LRO/CSUM first"); + NL_SET_ERR_MSG_MOD(extack, "Can't set XDP while host is implementing GRO_HW/CSUM, disable GRO_HW/CSUM first"); return -EOPNOTSUPP; } @@ -2612,15 +2612,15 @@ static int virtnet_set_features(struct net_device *dev, u64 offloads; int err; - if ((dev->features ^ features) & NETIF_F_LRO) { + if ((dev->features ^ features) & NETIF_F_GRO_HW) { if (vi->xdp_enabled) return -EBUSY; - if (features & NETIF_F_LRO) + if (features & NETIF_F_GRO_HW) offloads = vi->guest_offloads_capable; else offloads = vi->guest_offloads_capable & - ~GUEST_OFFLOAD_LRO_MASK; + ~GUEST_OFFLOAD_GRO_HW_MASK; err = virtnet_set_guest_offloads(vi, offloads); if (err) @@ -3100,9 +3100,9 @@ static int virtnet_probe(struct virtio_device *vdev) dev->features |= NETIF_F_RXCSUM; if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) || virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6)) - dev->features |= NETIF_F_LRO; + dev->features |= NETIF_F_GRO_HW; if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)) - dev->hw_features |= NETIF_F_LRO; + dev->hw_features |= NETIF_F_GRO_HW; dev->vlan_features = dev->features;