Comment 16 for bug 1551382

Reviewed: https://review.opencontrail.org/20241
Committed: http://github.org/Juniper/contrail-vrouter/commit/bba45f77c2b06b8b84c92054f3a17a67abe7969a
Submitter: Zuul
Branch: R2.20

commit bba45f77c2b06b8b84c92054f3a17a67abe7969a
Author: Anand H. Krishnan <email address hidden>
Date: Tue Mar 1 00:35:52 2016 +0530

Post GRO, label in fmd can't be used to check whether the packet
was tunneled or not

Once the packet is submitted for GRO, all datapath information is
lost. Post GRO, only values that are saved in the packet are the
vif and the nexthop. vif is a recent addition to the saved
information that helped us to identify which interface the packet
came from originally. Once the vif value was set properly, the logic
that checked whether the packet should be trapped to agent or not
based on the presence of label (basically fabric arp responses should
be trapped or not), misbehaved since label information is not saved
pre-GRO and hence not available in the metadata post GRO. For now,
fix the specific logic by checking whether the egress vrf is different
from the ingress vrf, which will be the case since physical interface
vrf will not be the same as vm's vrf.

Change-Id: Iba000889039bc8a5020fc11a462ba1b1a68ce1c8
Closes-BUG: #1551382