On 8/17/16 7:06 PM, Alexander Duyck wrote: > On Wed, Aug 17, 2016 at 4:23 PM, David Ahern <d...@cumulusnetworks.com> wrote: >> On 8/17/16 5:16 PM, Alexander Duyck wrote: >>>> diff --git a/net/openvswitch/actions.c b/net/openvswitch/actions.c >>>> index 1ecbd7715f6d..6d78f162a88b 100644 >>>> --- a/net/openvswitch/actions.c >>>> +++ b/net/openvswitch/actions.c >>>> @@ -167,6 +167,12 @@ static int push_mpls(struct sk_buff *skb, struct >>>> sw_flow_key *key, >>>> skb->mac_len); >>>> skb_reset_mac_header(skb); >>>> >>>> + /* for GSO: set MPLS as network header and encapsulated protocol >>>> + * header as inner network header >>>> + */ >>>> + skb_set_network_header(skb, skb->mac_len); >>>> + skb_set_inner_network_header(skb, skb->mac_len + MPLS_HLEN); >>>> + >>>> new_mpls_lse = (__be32 *)skb_mpls_header(skb); >>>> *new_mpls_lse = mpls->mpls_lse; >>>> >>> >>> So the one question I would have about this is how attached are you to >>> using the network_header to record the offset for the MPLS header? I >>> ask because I think from a hardware offloading perspective it would >>> make it much easier if instead you used the inner_mac_header to >>> represent the offset for the MPLS header. This way device drivers >>> could just skip over it like a VLAN and just use network and transport >>> header values like they would otherwise. >>> >> >> Where does the network_header relate to if I change the marker to >> inner_mac_header? Would it be skipped? > > No, the network header would still be the network header.
If core MPLS code (ie., non-OVS) does not do skb_reset_network_header(skb) after adding the MPLS label nothing works. Not even ping with small packets. tcpdump shows a completely mangled packet. Right now resetting the network_header to mpls is required.
