Hi Ian (or others), do you have any thoughts about this?
On Fri, Sep 28, 2018 at 04:24:33PM -0700, Ben Pfaff wrote: > I have been playing with the OFTest framework off and on over the last > few months and I believe it's caught an actual bug with its > DirectVlanPackets test. I'm appending a script that demonstrates it. > To see it, run "make sandbox" then execute the script inside it. > > At some level at least, the problem is in dpif-netdev, which during the > test logs messages like this indicating that a datapath flow can't be > found and therefore can't be modified: > > WARN|dummy@ovs-dummy: failed to put[modify] (No such file or > directory) ufid:b2fe59af-26bd-4aa0-960e-fd559dc10c54 > > skb_priority(0/0),skb_mark(0/0),ct_state(0/0),ct_zone(0/0),ct_mark(0/0),ct_label(0/0),recirc_id(0),dp_hash(0/0),in_port(1),packet_type(ns=0,id=0),eth(src=00:06:07:08:09:0a,dst=00:01:02:03:04:05),eth_type(0x8100),vlan(vid=1000/0x0,pcp=5/0x0),encap(eth_type(0x0800),ipv4(src=127.0.0.1/0.0.0.0,dst=127.0.0.1/0.0.0.0,proto=0/0,tos=0/0,ttl=64/0,frag=no)), > > actions:userspace(pid=0,controller(reason=7,dont_send=0,continuation=0,recirc_id=1,rule_cookie=0,controller_id=0,max_len=65535)) > > It's possible that the caller is screwing up by providing a flow match > different from one in the datapath flow table. I have not looked at > that question. But the really strange thing here is that the caller is > providing a ufid and dpif-netdev is ignoring it. When I make it honor > the ufid, like the following, then the test suddenly starts working. > This seems like a bug to me. > > (The following patch is not actually the real fix because the code > should still look at the key if no ufid was provided.) > > Any thoughts? > > Thanks, > > Ben. > > diff --git a/lib/dpif-netdev.c b/lib/dpif-netdev.c > index e322f5553fa8..4855cc08f7b7 100644 > --- a/lib/dpif-netdev.c > +++ b/lib/dpif-netdev.c > @@ -3273,7 +3273,7 @@ dp_netdev_flow_add(struct dp_netdev_pmd_thread *pmd, > > static int > flow_put_on_pmd(struct dp_netdev_pmd_thread *pmd, > - struct netdev_flow_key *key, > + struct netdev_flow_key *key OVS_UNUSED, > struct match *match, > ovs_u128 *ufid, > const struct dpif_flow_put *put, > @@ -3287,7 +3287,7 @@ flow_put_on_pmd(struct dp_netdev_pmd_thread *pmd, > } > > ovs_mutex_lock(&pmd->flow_mutex); > - netdev_flow = dp_netdev_pmd_lookup_flow(pmd, key, NULL); > + netdev_flow = dp_netdev_pmd_find_flow(pmd, ufid, NULL, 0); > if (!netdev_flow) { > if (put->flags & DPIF_FP_CREATE) { > if (cmap_count(&pmd->flow_table) < MAX_FLOWS) { > > > > --8<--------------------------cut here-------------------------->8-- > > #! /bin/sh -ex > > # Create a bridge and add port p1 on port 1, p2 on port 2 > ovs-appctl vlog/set netdev_dummy dpif > ovs-vsctl --if-exists del-br br0 \ > -- add-br br0 \ > -- add-port br0 p1 -- set interface p1 ofport_request=1 > options:tx_pcap=p1-tx.pcap options:rxq_pcap=p1-rx.pcap \ > -- add-port br0 p2 -- set interface p2 ofport_request=2 > options:tx_pcap=p2-tx.pcap options:rxq_pcap=p2-rx.pcap > > # Add a flow that directs some packets received on p1 to p2 and the > # rest back out p1. > # > # Then inject a packet of the form that should go to p2. Dump the > # datapath flow to see that it goes to p2 ("actions:2"). Trace the > # same packet for good measure, to also see that it should go to p2. > packet=00010203040500060708090a8100a3e80800450000140001000040007ce77f0000017f000001 > ovs-ofctl add-flow br0 > priority=1,ip,in_port=1,dl_src=00:06:07:08:09:0a,dl_dst=00:01:02:03:04:05,actions=output:2 > ovs-ofctl add-flow br0 priority=0,in_port=1,actions=IN_PORT > ovs-appctl netdev-dummy/receive p1 $packet > ovs-appctl ofproto/trace br0 in_port=p1 $packet > ovs-appctl dpif/dump-flows br0 > > # Delete the flows, then add new flows that would not match the same > # packet as before. > ovs-ofctl del-flows br0 > ovs-ofctl add-flow br0 > priority=1,in_port=1,dl_src=00:06:07:08:09:0a,dl_dst=00:01:02:03:04:05,dl_type=0x0801,actions=output:2 > ovs-ofctl add-flow br0 priority=0,in_port=1,actions=IN_PORT > > # Give the datapath a few seconds to revalidate. > sleep 2 > > # Now inject the same packet again. It should go to p1 because it > # only matches the priority-0 flow, as shown by the trace. However, instead, > # the original datapath flow is still there and its counters get incremented. > ovs-appctl netdev-dummy/receive p1 $packet > ovs-appctl ofproto/trace br0 in_port=p1 $packet > ovs-appctl dpif/dump-flows br0 > > # Give the datapath some time to expire the flow. > sleep 12 > > # Try again. > ovs-appctl netdev-dummy/receive p1 $packet > ovs-appctl ofproto/trace br0 in_port=p1 $packet > ovs-appctl dpif/dump-flows br0 _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev