From: Jason Wang jasowang@redhat.com
[ Upstream commit dbcf24d153884439dad30484a0e3f02350692e4c ]
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 mst@redhat.com Reported-by: Ivan ivan@prestigetransportation.com Tested-by: Ivan ivan@prestigetransportation.com Signed-off-by: Jason Wang jasowang@redhat.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- 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 a47cf77a0b08..cbe47eed7cc3 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)) @@ -2466,7 +2466,7 @@ 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; }
@@ -2597,15 +2597,15 @@ 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) @@ -3080,9 +3080,9 @@ 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;