[PATCH net v2 2/2] selftests: openvswitch: add tests for tunnel vport refcounting

Ilya Maximets
2026-04-30T23:39:12Z

There were a few issues found with the tunnel vport types around the
vport destruction code. Add some basic tests, so at least we know that
they can be properly added and removed without obvious issues.

The test creates OVS datapath, adds a non-LWT tunnel port, makes sure
they are created, and then removes the datapath and waits for all the
ports to be gone.

The dpctl script had a few bugs in the none-lwt tunnel creation code,
so fixing them as well to make the testing possible:
- The type of the --lwt option changed in order to properly disable it.
- Removed byte order conversion for the port numbers, as the value
supposed to be in the host order.
- Added missing 'gre' choice for the tunnel type.

Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
---
.../selftests/net/openvswitch/openvswitch.sh | 37 +++++++++++++++++++
.../selftests/net/openvswitch/ovs-dpctl.py | 19 +++++++---
2 files changed, 50 insertions(+), 6 deletions(-)

diff --git a/tools/testing/selftests/net/openvswitch/openvswitch.sh b/tools/testing/selftests/net/openvswitch/openvswitch.sh
index b327d3061ed53..3cdd953f68132 100755
--- a/tools/testing/selftests/net/openvswitch/openvswitch.sh
+++ b/tools/testing/selftests/net/openvswitch/openvswitch.sh
@@ -26,6 +26,7 @@ tests="
netlink_checks ovsnl: validate netlink attrs and settings
upcall_interfaces ovs: test the upcall interfaces
tunnel_metadata ovs: test extraction of tunnel metadata
+ tunnel_refcount ovs: test tunnel vport reference cleanup
drop_reason drop: test drop reasons are emitted
psample psample: Sampling packets with psample"

@@ -830,6 +831,42 @@ test_tunnel_metadata() {
return 0
}

+test_tunnel_refcount() {
+ sbxname="test_tunnel_refcount"
+ sbx_add "${sbxname}" || return 1
+
+ ovs_sbx "${sbxname}" ip netns add trefns || return 1
+ on_exit "ovs_sbx ${sbxname} ip netns del trefns"
+
+ for tun_type in gre vxlan geneve; do
+ info "testing ${tun_type} tunnel vport refcount"
+
+ ovs_sbx "${sbxname}" ip netns exec trefns \
+ python3 $ovs_base/ovs-dpctl.py \
+ add-dp dp-${tun_type} || return 1
+
+ ovs_sbx "${sbxname}" ip netns exec trefns \
+ python3 $ovs_base/ovs-dpctl.py \
+ add-if --no-lwt -t ${tun_type} \
+ dp-${tun_type} ovs-${tun_type}0 || return 1
+
+ ovs_wait ip -netns trefns link show \
+ ovs-${tun_type}0 >/dev/null 2>&1 || return 1
+
+ info "deleting dp - may hang if reference counting is broken"
+ ovs_sbx "${sbxname}" ip netns exec trefns \
+ python3 $ovs_base/ovs-dpctl.py \
+ del-dp dp-${tun_type} &
+
+ dev_removed() {
+ ! ip -netns trefns link show "$1" >/dev/null 2>&1
+ }
+ ovs_wait dev_removed dp-${tun_type} || return 1
+ ovs_wait dev_removed ovs-${tun_type}0 || return 1
+ done
+ return 0
+}
+
run_test() {
(
tname="$1"
diff --git a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py
index 848f61fdcee09..bbe35e2718d26 100644
--- a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py
+++ b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py
@@ -11,7 +11,6 @@ import logging
import math
import multiprocessing
import re
-import socket
import struct
import sys
import time
@@ -2069,7 +2068,7 @@ class OvsVport(GenericNetlinkSocket):
elif vport_type == "internal":
return OvsVport.OVS_VPORT_TYPE_INTERNAL
elif vport_type == "gre":
- return OvsVport.OVS_VPORT_TYPE_INTERNAL
+ return OvsVport.OVS_VPORT_TYPE_GRE
elif vport_type == "vxlan":
return OvsVport.OVS_VPORT_TYPE_VXLAN
elif vport_type == "geneve":
@@ -2121,6 +2120,7 @@ class OvsVport(GenericNetlinkSocket):
)

TUNNEL_DEFAULTS = [("geneve", 6081),
+ ("gre", 0),
("vxlan", 4789)]

for tnl in TUNNEL_DEFAULTS:
@@ -2129,9 +2129,13 @@ class OvsVport(GenericNetlinkSocket):
dport = tnl[1]

if not lwt:
+ if tnl[0] == "gre":
+ # GRE tunnels have no options.
+ break
+
vportopt = OvsVport.ovs_vport_msg.vportopts()
vportopt["attrs"].append(
- ["OVS_TUNNEL_ATTR_DST_PORT", socket.htons(dport)]
+ ["OVS_TUNNEL_ATTR_DST_PORT", dport]
)
msg["attrs"].append(
["OVS_VPORT_ATTR_OPTIONS", vportopt]
@@ -2145,6 +2149,9 @@ class OvsVport(GenericNetlinkSocket):
geneve_port=dport,
geneve_collect_metadata=True,
geneve_udp_zero_csum6_rx=1)
+ elif tnl[0] == "gre":
+ ipr.link("add", ifname=vport_ifname, kind="gretap",
+ gre_collect_metadata=True)
elif tnl[0] == "vxlan":
ipr.link("add", ifname=vport_ifname, kind=tnl[0],
vxlan_learning=0, vxlan_collect_metadata=1,
@@ -2563,7 +2570,7 @@ def print_ovsdp_full(dp_lookup_rep, ifindex, ndb=NDB(), vpl=OvsVport()):
if vpo:
dpo = vpo.get_attr("OVS_TUNNEL_ATTR_DST_PORT")
if dpo:
- opts += " tnl-dport:%s" % socket.ntohs(dpo)
+ opts += " tnl-dport:%s" % dpo
print(
" port %d: %s (%s%s)"
% (
@@ -2632,7 +2639,7 @@ def main(argv):
"--ptype",
type=str,
default="netdev",
- choices=["netdev", "internal", "geneve", "vxlan"],
+ choices=["netdev", "internal", "gre", "geneve", "vxlan"],
help="Interface type (default netdev)",
)
addifcmd.add_argument(
@@ -2645,7 +2652,7 @@ def main(argv):
addifcmd.add_argument(
"-l",
"--lwt",
- type=bool,
+ action=argparse.BooleanOptionalAction,
default=True,
help="Use LWT infrastructure instead of vport (default true)."
)
--
2.53.0