[ovs-dev] assertion failing in commit_set_ipv4_action(), flow->nw_proto != base_flow->nw_proto

[Thomas Morin]

Hi,

We're hitting an issue with an assert failing in 
commit_set_ipv4_action(), resulting in a core dump:

2016-11-29T09:22:48.829Z|00005|util(revalidator77)|EMER|lib/odp-util.c:5208: 
assertion flow->nw_proto == base_flow->nw_proto && flow->nw_frag == 
base_flow->nw_frag failed in commit_set_ipv4_action()

Adding a few log statements gives more info:

2016-11-29T09:22:48.829Z|00001|odp_util(revalidator77)|WARN|commit_set_ipv4_action 
assert will fail....
2016-11-29T09:22:48.829Z|00002|odp_util(revalidator77)|WARN|  base_flow: 
ip,in_port=3,dl_vlan=1,dl_vlan_pcp=0,dl_src=fa:16:3e:84:02:4a,dl_dst=00:00:5e:00:43:64,nw_src=0.0.0.0,nw_dst=0.0.0.0,nw_proto=0,nw_tos=0,nw_ecn=0,nw_ttl=0
2016-11-29T09:22:48.829Z|00003|odp_util(revalidator77)|WARN|  flow: 
tcp,in_port=3,dl_vlan=1,dl_vlan_pcp=0,dl_src=fa:16:3e:84:02:4a,dl_dst=00:00:5e:00:43:64,nw_src=10.0.1.21,nw_dst=10.0.0.3,nw_tos=0,nw_ecn=0,nw_ttl=64,tp_src=50962,tp_dst=8080,tcp_flags=psh|ack
2016-11-29T09:22:48.829Z|00004|odp_util(revalidator77)|WARN| 
  flow->nw_proto (6) != base_flow->nw_proto (0)

As show above the assert triggers because flow->nw_proto != 
base_flow->nw_proto (6 != 0).

The assert triggers, not on a new flow but for a flow for which traffic 
has been flowing for some time (tcp 50962 to 8080 in the example above).

The issue can be reproduced on a lab platform, happening each time 
approximately 5 minutes after starting a test service (a few VMs).

This is with v2.5.1, with the DKMS datapath on Ubuntu 14.04.
It reproduces as well with branch-2.5 HEAD as well.

Any idea ?

-Thomas