On 5/20/26 2:23 AM, Jacob Tanenbaum via dev wrote: > Hi Xavier > Hi Xavier, Jacob,
> Looks good to me. > > Acked-by: Jacob Tanenbaum <[email protected]> > Thanks for the patch and review! > On Tue, May 19, 2026 at 8:56 AM Xavier Simonart via dev < > [email protected]> wrote: > >> If dynamic routing was enabled on a logical router port with no >> explicit IPs configured, then when the BGP control plane was learning >> a route in the VRF monitored by that logical router port, ovn-northd >> was generating syntactically incorrect logical flows (with >> reg5 = (null) action) causing that route to never actually be >> installed. >> >> Reported-at: https://redhat.atlassian.net/browse/FDP-3583a >> Fixes: 966ca1c919ce ("northd: Handle learned routes.") >> Assisted-by: Claude Opus 4.6, Claude Code >> Signed-off-by: Xavier Simonart <[email protected]> >> --- >> northd/northd.c | 37 +++++++++++++++++++------------ >> tests/ovn-northd.at | 53 +++++++++++++++++++++++++++++++++++++++++++++ >> 2 files changed, 76 insertions(+), 14 deletions(-) >> >> diff --git a/northd/northd.c b/northd/northd.c >> index 4162143de..0fdf6db42 100644 >> --- a/northd/northd.c >> +++ b/northd/northd.c >> @@ -12748,10 +12748,15 @@ add_ecmp_symmetric_reply_flows(struct >> lflow_table *lflows, >> ds_cstr(route_match)); >> ds_clear(&actions); >> ds_put_format(&actions, "ip.ttl--; flags.loopback = 1; " >> - "eth.src = %s; %s = %s; outport = %s; next;", >> - out_port->lrp_networks.ea_s, >> - is_ipv4_nexthop ? REG_SRC_IPV4 : REG_SRC_IPV6, >> - port_ip, out_port->json_key); >> + "eth.src = %s; ", >> + out_port->lrp_networks.ea_s); >> + if (port_ip) { >> + ds_put_format(&actions, "%s = %s; ", >> + is_ipv4_nexthop ? REG_SRC_IPV4 : REG_SRC_IPV6, >> + port_ip); >> + } >> + ds_put_format(&actions, "outport = %s; next;", >> + out_port->json_key); >> ovn_lflow_add(lflows, od, S_ROUTER_IN_IP_ROUTING, 10300, >> ds_cstr(&match), >> ds_cstr(&actions), lflow_ref, >> WITH_HINT(route->source_hint)); >> >> @@ -12891,13 +12896,15 @@ build_ecmp_route_flow(struct lflow_table *lflows, >> ds_put_format(&actions, "%s = ", >> is_ipv4_nexthop ? REG_NEXT_HOP_IPV4 : >> REG_NEXT_HOP_IPV6); >> ipv6_format_mapped(route->nexthop, &actions); >> - ds_put_format(&actions, "; " >> - "%s = %s; " >> - "eth.src = %s; " >> + if (route->lrp_addr_s) { >> + ds_put_format(&actions, "; %s = %s", >> + is_ipv4_nexthop ? REG_SRC_IPV4 : REG_SRC_IPV6, >> + route->lrp_addr_s); >> + } >> + ds_put_format(&actions, >> + "; eth.src = %s; " >> "outport = %s; " >> REGBIT_NEXTHOP_IS_IPV4" = %d; ", >> - is_ipv4_nexthop ? REG_SRC_IPV4 : REG_SRC_IPV6, >> - route->lrp_addr_s, >> route->out_port->lrp_networks.ea_s, >> route->out_port->json_key, >> is_ipv4_nexthop); >> @@ -12957,15 +12964,17 @@ add_route(struct lflow_table *lflows, const >> struct ovn_datapath *od, >> REG_NEXT_HOP_IPV6, >> is_ipv4_prefix ? "4" : "6"); >> } >> - ds_put_format(&common_actions, "; " >> - "%s = %s; " >> - "eth.src = %s; " >> + if (lrp_addr_s) { >> + ds_put_format(&common_actions, "; %s = %s", >> + is_ipv4_nexthop ? REG_SRC_IPV4 : REG_SRC_IPV6, >> + lrp_addr_s); >> + } >> + ds_put_format(&common_actions, >> + "; eth.src = %s; " >> "outport = %s; " >> "flags.loopback = 1; " >> REGBIT_NEXTHOP_IS_IPV4" = %d; " >> "next;", >> - is_ipv4_nexthop ? REG_SRC_IPV4 : REG_SRC_IPV6, >> - lrp_addr_s, >> op->lrp_networks.ea_s, >> op->json_key, >> is_ipv4_nexthop); >> diff --git a/tests/ovn-northd.at b/tests/ovn-northd.at >> index 501f78b67..6f8c1d30e 100644 >> --- a/tests/ovn-northd.at >> +++ b/tests/ovn-northd.at >> @@ -16317,6 +16317,59 @@ OVN_CLEANUP_NORTHD >> AT_CLEANUP >> ]) >> >> +OVN_FOR_EACH_NORTHD_NO_HV([ >> +AT_SETUP([dynamic-routing - learned routes on unnumbered LRP]) >> +AT_KEYWORDS([dynamic-routing]) >> +ovn_start >> + >> +check ovn-nbctl lr-add lr0 >> +check ovn-nbctl set Logical_Router lr0 option:dynamic-routing=true >> +check ovn-nbctl lrp-add lr0 lrp1 00:00:00:00:ff:01 10.0.0.1/24 >> +check ovn-nbctl lrp-add lr0 lrp2 00:00:00:00:ff:02 >> +check ovn-nbctl --wait=sb lrp-add lr0 lrp3 00:00:00:00:ff:03 >> +datapath=$(fetch_column datapath_binding _uuid external_ids:name=lr0) >> +lrp2=$(fetch_column port_binding _uuid logical_port=lrp2) >> +lrp3=$(fetch_column port_binding _uuid logical_port=lrp3) >> + >> +check_uuid ovn-sbctl create Learned_Route \ >> + datapath=$datapath \ >> + logical_port=$lrp2 \ Nit: misalignment >> + ip_prefix=42.42.42.42/32 \ >> + nexthop=192.168.2.42 >> +check ovn-nbctl --wait=sb sync >> + >> +ovn-sbctl dump-flows lr0 > lr0flows >> +AT_CHECK([grep -F "42.42.42.42" lr0flows | grep -c '(null)'], [1], [0 >> +]) I wouldn't add this check TBH, we have the positive check just after. >> + >> +AT_CHECK([grep -F "42.42.42.42" lr0flows | ovn_strip_lflows], [0], [dnl >> + table=??(lr_in_ip_routing ), priority=258 , match=(reg7 == 0 && >> ip4.dst == 42.42.42.42/32), action=(ip.ttl--; reg8[[0..15]] = 0; reg0 = >> 192.168.2.42; eth.src = 00:00:00:00:ff:02; outport = "lrp2"; flags.loopback >> = 1; reg9[[9]] = 1; next;) >> +]) >> + >> +check_uuid ovn-sbctl create Learned_Route \ >> + datapath=$datapath \ >> + logical_port=$lrp3 \ >> + ip_prefix=42.42.42.42/32 \ >> + nexthop=192.168.3.42 >> +check ovn-nbctl --wait=sb sync >> + >> +ovn-sbctl dump-flows lr0 > lr0flows >> +AT_CHECK([grep -c '(null)' lr0flows], [1], [0 >> +]) Same here. >> + >> +AT_CHECK([grep -w "lr_in_ip_routing" lr0flows | grep -F "42.42.42.42" | >> ovn_strip_lflows], [0], [dnl >> + table=??(lr_in_ip_routing ), priority=258 , match=(reg7 == 0 && >> ip4.dst == 42.42.42.42/32), action=(ip.ttl--; flags.loopback = 1; >> reg8[[0..15]] = 1; reg8[[16..31]] = select(1, 2);) >> +]) >> + >> +AT_CHECK([grep "lr_in_ip_routing_ecmp" lr0flows | grep "42" | sed -e >> 's/reg8\[[16..31\]] == [[12]]/reg8\[[16..31\]] == ??/g' | ovn_strip_lflows >> | sort], [0], [dnl Nit: sort not needed, it's part of ovn_strip_lflows. >> + table=??(lr_in_ip_routing_ecmp), priority=100 , match=(reg8[[0..15]] >> == 1 && reg8[[16..31]] == ??), action=(reg0 = 192.168.2.42; eth.src = >> 00:00:00:00:ff:02; outport = "lrp2"; reg9[[9]] = 1; next;) >> + table=??(lr_in_ip_routing_ecmp), priority=100 , match=(reg8[[0..15]] >> == 1 && reg8[[16..31]] == ??), action=(reg0 = 192.168.3.42; eth.src = >> 00:00:00:00:ff:03; outport = "lrp3"; reg9[[9]] = 1; next;) >> +]) >> + >> +OVN_CLEANUP_NORTHD >> +AT_CLEANUP >> +]) >> + >> OVN_FOR_EACH_NORTHD_NO_HV([ >> AT_SETUP([dynamic-routing - route learning cleanup - router recreation]) >> AT_KEYWORDS([dynamic-routing]) >> -- >> 2.47.1 >> With the small nits addressed, I applied this patch to main and backported it to all stable branches down to 25.03. Best regards, Dumitru _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
