selftests: include bonding tests into the kselftest infra

This creates a test collection in drivers/net/bonding for bonding
specific kernel selftests.

The first test is a reproducer that provisions a bond and given the
specific order in how the ip-link(8) commands are issued the bond never
transmits an LACPDU frame on any of its slaves.

Signed-off-by: Jonathan Toppins <jtoppins@redhat.com>
Acked-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

MAINTAINERS

@@ -3679,6 +3679,7 @@ F:	Documentation/networking/bonding.rst
 F:	drivers/net/bonding/
 F:	include/net/bond*
 F:	include/uapi/linux/if_bonding.h
+F:	tools/testing/selftests/net/bonding/
 
 BOSCH SENSORTEC BMA400 ACCELEROMETER IIO DRIVER
 M:	Dan Robertson <dan@dlrobertson.com>

tools/testing/selftests/Makefile

@@ -12,6 +12,7 @@ TARGETS += cpu-hotplug
 TARGETS += damon
 TARGETS += drivers/dma-buf
 TARGETS += drivers/s390x/uvdevice
+TARGETS += drivers/net/bonding
 TARGETS += efivarfs
 TARGETS += exec
 TARGETS += filesystems

tools/testing/selftests/drivers/net/bonding/Makefile

@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+# Makefile for net selftests
+
+TEST_PROGS := bond-break-lacpdu-tx.sh
+
+include ../../../lib.mk

tools/testing/selftests/drivers/net/bonding/bond-break-lacpdu-tx.sh

@@ -0,0 +1,81 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+
+# Regression Test:
+#   Verify LACPDUs get transmitted after setting the MAC address of
+#   the bond.
+#
+# https://bugzilla.redhat.com/show_bug.cgi?id=2020773
+#
+#       +---------+
+#       | fab-br0 |
+#       +---------+
+#            |
+#       +---------+
+#       |  fbond  |
+#       +---------+
+#        |       |
+#    +------+ +------+
+#    |veth1 | |veth2 |
+#    +------+ +------+
+#
+# We use veths instead of physical interfaces
+
+set -e
+tmp=$(mktemp -q dump.XXXXXX)
+cleanup() {
+	ip link del fab-br0 >/dev/null 2>&1 || :
+	ip link del fbond  >/dev/null 2>&1 || :
+	ip link del veth1-bond  >/dev/null 2>&1 || :
+	ip link del veth2-bond  >/dev/null 2>&1 || :
+	modprobe -r bonding  >/dev/null 2>&1 || :
+	rm -f -- ${tmp}
+}
+
+trap cleanup 0 1 2
+cleanup
+sleep 1
+
+# create the bridge
+ip link add fab-br0 address 52:54:00:3B:7C:A6 mtu 1500 type bridge \
+	forward_delay 15
+
+# create the bond
+ip link add fbond type bond mode 4 miimon 200 xmit_hash_policy 1 \
+	ad_actor_sys_prio 65535 lacp_rate fast
+
+# set bond address
+ip link set fbond address 52:54:00:3B:7C:A6
+ip link set fbond up
+
+# set again bond sysfs parameters
+ip link set fbond type bond ad_actor_sys_prio 65535
+
+# create veths
+ip link add name veth1-bond type veth peer name veth1-end
+ip link add name veth2-bond type veth peer name veth2-end
+
+# add ports
+ip link set fbond master fab-br0
+ip link set veth1-bond down master fbond
+ip link set veth2-bond down master fbond
+
+# bring up
+ip link set veth1-end up
+ip link set veth2-end up
+ip link set fab-br0 up
+ip link set fbond up
+ip addr add dev fab-br0 10.0.0.3
+
+tcpdump -n -i veth1-end -e ether proto 0x8809 >${tmp} 2>&1 &
+sleep 15
+pkill tcpdump >/dev/null 2>&1
+rc=0
+num=$(grep "packets captured" ${tmp} | awk '{print $1}')
+if test "$num" -gt 0; then
+	echo "PASS, captured ${num}"
+else
+	echo "FAIL"
+	rc=1
+fi
+exit $rc

tools/testing/selftests/drivers/net/bonding/config

@@ -0,0 +1 @@
+CONFIG_BONDING=y

tools/testing/selftests/drivers/net/bonding/settings

@@ -0,0 +1 @@
+timeout=60