[ovs-dev] [RFC] Extremely crude conntrack resubmit test case

[Russell Bryant]

This patch includes a really crude test case demonstrating the problem
I'm seeing with resubmitting to a table that does ct() multiple times.
It only seems to work on the first resubmit.

The test case is REALLY crude, but I think it shows the issue.  The test
case will always fail as written so I can look at the flows.  I run this
with:

  $ sudo make check-kmod TESTSUITEFLAGS="-k resubmit -v"

The interesting part is the flows output at the end.  Here's what I see:

>  cookie=0x0, duration=1.037s, table=0, n_packets=2, n_bytes=84, priority=150,arp actions=NORMAL
>  cookie=0x0, duration=1.037s, table=0, n_packets=3, n_bytes=266, priority=100,in_port=1 actions=drop
>  cookie=0x0, duration=1.037s, table=0, n_packets=2, n_bytes=168, priority=100,in_port=2 actions=drop
>  cookie=0x0, duration=1.036s, table=0, n_packets=1, n_bytes=98, priority=100,ip,in_port=LOCAL actions=load:0x1->NXM_NX_REG0[0..15],resubmit(,1),load:0x2->NXM_NX_REG0[0..15],resubmit(,1)
>  cookie=0x0, duration=1.036s, table=0, n_packets=1, n_bytes=78, priority=1 actions=drop
>  cookie=0x0, duration=1.035s, table=1, n_packets=1, n_bytes=98, priority=100,ip actions=ct(table=2,zone=NXM_NX_REG0[0..15])
>  cookie=0x0, duration=1.035s, table=2, n_packets=1, n_bytes=98, priority=100,ip,reg0=0x1 actions=output:1
>  cookie=0x0, duration=1.034s, table=2, n_packets=0, n_bytes=0, priority=100,ip,reg0=0x2 actions=output:2

There is a flow in table 0 that resubmits to table 1 twice.  It should
result in the packet being output to ports 1 and 2 in table 2.  It only
hits tables 1 and 2 once, which is the first resubmit from the flow in
table 0.

I'm running this in a new VM and the following message seen in my
OpenStack test environment does *not* show up at all in this
environment: "openvswitch: ovs-system: deferred action limit reached,
drop recirc action".
---
 tests/system-traffic.at | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/tests/system-traffic.at b/tests/system-traffic.at
index 3b2de83..80b96c0 100644
--- a/tests/system-traffic.at
+++ b/tests/system-traffic.at
@@ -1266,3 +1266,43 @@ NS_CHECK_EXEC([at_ns0], [ping -s 3200 -q -c 3 -i 0.3 -w 2 10.1.1.100 | FORMAT_PI
 
 OVS_TRAFFIC_VSWITCHD_STOP
 AT_CLEANUP
+
+AT_SETUP([conntrack - resubmit to ct multiple times])
+CHECK_CONNTRACK()
+
+OVS_TRAFFIC_VSWITCHD_START(
+   [set-fail-mode br0 secure -- ])
+
+ADD_NAMESPACES(at_ns0, at_ns1)
+
+AT_CHECK([ip addr add dev br0 "10.1.1.1/24"])
+AT_CHECK([ip link set dev br0 up])
+on_exit 'ip addr del dev br0 "10.1.1.1/24"'
+ADD_VETH(p0, at_ns0, br0, "10.1.1.2/24")
+ADD_VETH(p1, at_ns1, br0, "10.1.1.3/24")
+
+AT_DATA([flows.txt], [dnl
+table=0,priority=150,arp,action=normal
+table=0,priority=100,in_port=1,action=drop
+table=0,priority=100,in_port=2,action=drop
+table=0,priority=100,ip,in_port=LOCAL,action=load:1->NXM_NX_REG0[[0..15]],resubmit(,1),load:2->NXM_NX_REG0[[0..15]],resubmit(,1)
+table=0,priority=1,action=drop
+
+table=1,priority=100,ip,action=ct(table=2,zone=NXM_NX_REG0[[0..15]])
+
+table=2,priority=100,ip,reg0=1,action=output:1
+table=2,priority=100,ip,reg0=2,action=output:2
+])
+
+AT_CHECK([ovs-ofctl add-flows br0 flows.txt])
+
+AT_CHECK([ping -q -c 1 -w 1 -I 10.1.1.1 10.1.1.2 | FORMAT_PING], [0], [dnl
+1 packets transmitted, 0 received, 100% packet loss, time 0ms
+])
+
+AT_CHECK([ovs-ofctl -O OpenFlow13 show br0 ; ovs-ofctl -O OpenFlow13 dump-flows br0 | cut -f3- -d','], [0], [dnl
+always fail and show me the output
+])
+
+OVS_TRAFFIC_VSWITCHD_STOP
+AT_CLEANUP
-- 
2.5.0