[ovs-dev] [PATCH ovn] ofctrl: Do not link a desired flow twice.

[Dumitru Ceara]

Depending on the logical flow matches, multiple SB flows can point to
the same desired flow.  If it happens that the desired flow conflicts
with a more restrictive (already installed) flow, then we shouldn't try
to add the desired flow multiple times to the list maintained for the
installed flow.

Fixes: 6f0b1e02d9ab ("ofctrl: Incremental processing for flow installation by tracking.")
Signed-off-by: Dumitru Ceara <dceara at redhat.com>
---
Note: I'm quite sure about the "Fixes" tag above, however, I couldn't
reproduce the issue without the following commit:
  dadae4f800cc ("ofctrl.c: Only merge actions for conjunctive flows.")
---
 controller/ofctrl.c |  3 +--
 tests/ovn.at        | 19 +++++++++++++++++++
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/controller/ofctrl.c b/controller/ofctrl.c
index 9d62e12..f2bb93a 100644
--- a/controller/ofctrl.c
+++ b/controller/ofctrl.c
@@ -1975,8 +1975,7 @@ update_installed_flows_by_track(struct ovn_desired_flow_table *flow_table,
                 /* The installed flow is installed for f, but f has change
                  * tracked, so it must have been modified. */
                 installed_flow_mod(&i->flow, &f->flow, msgs);
-                ovn_flow_log(&i->flow, "updating installed (tracked)");
-            } else {
+            } else if (!f->installed_flow) {
                 /* Adding a new flow that conflicts with an existing installed
                  * flow, so add it to the link.  If this flow becomes active,
                  * e.g., it is less restrictive than the previous active flow
diff --git a/tests/ovn.at b/tests/ovn.at
index 55ea6d1..933958e 100644
--- a/tests/ovn.at
+++ b/tests/ovn.at
@@ -13955,6 +13955,25 @@ AT_CHECK([as hv1 ovs-ofctl dump-flows br-int table=45 | ofctl_strip_all | \
  table=45, priority=1003,ip,metadata=0x1,nw_src=10.0.0.42 actions=conjunction()
 ])
 
+# Add another ACL that overlaps with the existing less restrictive ones.
+check ovn-nbctl acl-add ls1 to-lport 3 'udp || ((ip4.src==10.0.0.1 || ip4.src==10.0.0.2) && (ip4.dst == 10.0.0.3 || ip4.dst == 10.0.0.4))' allow
+check ovn-nbctl --wait=hv sync
+
+AT_CHECK([as hv1 ovs-ofctl dump-flows br-int table=45 | ofctl_strip_all | \
+   grep "priority=1003" | \
+   sed 's/conjunction([[^)]]*)/conjunction()/g' | sort], [0], [dnl
+ table=45, priority=1003,conj_id=2,ip,metadata=0x1 actions=resubmit(,46)
+ table=45, priority=1003,conj_id=3,ip,metadata=0x1 actions=resubmit(,46)
+ table=45, priority=1003,conj_id=4,ip,metadata=0x1 actions=resubmit(,46)
+ table=45, priority=1003,ip,metadata=0x1,nw_dst=10.0.0.3 actions=conjunction(),conjunction(),conjunction()
+ table=45, priority=1003,ip,metadata=0x1,nw_dst=10.0.0.4 actions=conjunction(),conjunction(),conjunction()
+ table=45, priority=1003,ip,metadata=0x1,nw_src=10.0.0.1 actions=resubmit(,46)
+ table=45, priority=1003,ip,metadata=0x1,nw_src=10.0.0.2 actions=conjunction(),conjunction()
+ table=45, priority=1003,ip,metadata=0x1,nw_src=10.0.0.42 actions=conjunction()
+ table=45, priority=1003,udp,metadata=0x1 actions=resubmit(,46)
+ table=45, priority=1003,udp6,metadata=0x1 actions=resubmit(,46)
+])
+
 OVN_CLEANUP([hv1])
 AT_CLEANUP
 
-- 
1.8.3.1