Merge branch 'selftests-fixes-for-kernel-ci'

Petr Machata says:

====================
selftests: Fixes for kernel CI

As discussed on the bi-weekly call on Jan 30, and in mailing around
kernel CI effort, some changes are desirable in the suite of forwarding
selftests the better to work with the CI tooling. Namely:

- The forwarding selftests use a configuration file where names of
  interfaces are defined and various variables can be overridden. There
  is also forwarding.config.sample that users can use as a template to
  refer to when creating the config file. What happens a fair bit is
  that users either do not know about this at all, or simply forget, and
  are confused by cryptic failures about interfaces that cannot be
  created.

  In patches #1 - #3 have lib.sh just be the single source of truth with
  regards to which variables exist. That includes the topology variables
  which were previously only in the sample file, and any "tweak
  variables", such as what tools to use, sleep times, etc.

  forwarding.config.sample then becomes just a placeholder with a couple
  examples. Unless specific HW should be exercised, or specific tools
  used, the defaults are usually just fine.

- Several net/forwarding/ selftests (and one net/ one) cannot be run on
  veth pairs, they need an actual HW interface to run on. They are
  generic in the sense that any capable HW should pass them, which is
  why they have been put to net/forwarding/ as opposed to drivers/net/,
  but they do not generalize to veth. The fact that these tests are in
  net/forwarding/, but still complaining when run, is confusing.

  In patches #4 - #6 move these tests to a new directory
  drivers/net/hw.

- The following patches extend the codebase to handle well test results
  other than pass and fail.

  Patch #7 is preparatory. It converts several log_test_skip to XFAIL,
  so that tests do not spuriously end up returning non-0 when they
  are not supposed to.

  In patches #8 - #10, introduce some missing ksft constants, then support
  having those constants in RET, and then finally in EXIT_STATUS.

- The traffic scheduler tests generate a large amount of network traffic
  to test the behavior of the scheduler. This demands a relatively
  high-performance computer. On slow machines, such as with a debugging
  kernel, the test would spuriously fail.

  It can still be useful to "go through the motions" though, to possibly
  catch bugs in setup of the scheduler graph and passing packets around.
  Thus we still want to run the tests, just with lowered demands.

  To that end, in patches #11 - #12, introduce an environment variable
  KSFT_MACHINE_SLOW, with obvious meaning. Tests can then make checks
  more lenient, such as mark failures as XFAIL. A helper, xfail_on_slow,
  is provided to mark performance-sensitive parts of the selftest.

- In patch #13, use a similar mechanism to mark a NH group stats
  selftest to XFAIL HW stats tests when run on VETH pairs.

- All these changes complicate the hitherto straightforward logging and
  checking logic, so in patch #14, add a selftest that checks this
  functionality in lib.sh.

v1 (vs. an RFC circulated through linux-kselftest):
- Patch #9:
    - Clarify intended usage by s/set_ret/ret_set_ksft_status/,
      s/nret/ksft_status/
====================

Link: https://lore.kernel.org/r/cover.1711464583.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

28 files changed, 565 insertions, 171 deletions

diff --git a/tools/testing/selftests/drivers/net/hw/Makefile b/tools/testing/selftests/drivers/net/hw/Makefile
new file mode 100644
index 00000000000000..2259a39a70edf5
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/hw/Makefile
@@ -0,0 +1,25 @@
+# SPDX-License-Identifier: GPL-2.0+ OR MIT
+
+TEST_PROGS = \
+	devlink_port_split.py \
+	ethtool.sh \
+	ethtool_extended_state.sh \
+	ethtool_mm.sh \
+	ethtool_rmon.sh \
+	hw_stats_l3.sh \
+	hw_stats_l3_gre.sh \
+	loopback.sh \
+	#
+
+TEST_FILES := \
+	ethtool_lib.sh \
+	#
+
+TEST_INCLUDES := \
+	../../../net/lib.sh \
+	../../../net/forwarding/lib.sh \
+	../../../net/forwarding/ipip_lib.sh \
+	../../../net/forwarding/tc_common.sh \
+	#
+
+include ../../../lib.mk
diff --git a/tools/testing/selftests/net/devlink_port_split.py b/tools/testing/selftests/drivers/net/hw/devlink_port_split.py
index 2d84c7a0be6b21..2d84c7a0be6b21 100755
--- a/tools/testing/selftests/net/devlink_port_split.py
+++ b/tools/testing/selftests/drivers/net/hw/devlink_port_split.py
diff --git a/tools/testing/selftests/net/forwarding/ethtool.sh b/tools/testing/selftests/drivers/net/hw/ethtool.sh
index aa2eafb7b24376..bb12d5d709493a 100755
--- a/tools/testing/selftests/net/forwarding/ethtool.sh
+++ b/tools/testing/selftests/drivers/net/hw/ethtool.sh
@@ -10,7 +10,8 @@ ALL_TESTS="
 	different_speeds_autoneg_on
 "
 NUM_NETIFS=2
-source lib.sh
+lib_dir=$(dirname "$0")
+source "$lib_dir"/../../../net/forwarding/lib.sh
 source ethtool_lib.sh
 
 h1_create()
@@ -286,8 +287,6 @@ different_speeds_autoneg_on()
 	ethtool -s $h1 autoneg on
 }
 
-skip_on_veth
-
 trap cleanup EXIT
 
 setup_prepare
diff --git a/tools/testing/selftests/net/forwarding/ethtool_extended_state.sh b/tools/testing/selftests/drivers/net/hw/ethtool_extended_state.sh
index 17f89c3b7c0206..a7584448416ea6 100755
--- a/tools/testing/selftests/net/forwarding/ethtool_extended_state.sh
+++ b/tools/testing/selftests/drivers/net/hw/ethtool_extended_state.sh
@@ -8,7 +8,8 @@ ALL_TESTS="
 "
 
 NUM_NETIFS=2
-source lib.sh
+lib_dir=$(dirname "$0")
+source "$lib_dir"/../../../net/forwarding/lib.sh
 source ethtool_lib.sh
 
 TIMEOUT=$((WAIT_TIMEOUT * 1000)) # ms
@@ -108,8 +109,6 @@ no_cable()
 	ip link set dev $swp3 down
 }
 
-skip_on_veth
-
 setup_prepare
 
 tests_run
diff --git a/tools/testing/selftests/net/forwarding/ethtool_lib.sh b/tools/testing/selftests/drivers/net/hw/ethtool_lib.sh
index b9bfb45085afd9..b9bfb45085afd9 100644
--- a/tools/testing/selftests/net/forwarding/ethtool_lib.sh
+++ b/tools/testing/selftests/drivers/net/hw/ethtool_lib.sh
diff --git a/tools/testing/selftests/net/forwarding/ethtool_mm.sh b/tools/testing/selftests/drivers/net/hw/ethtool_mm.sh
index 50d5bfb17ef184..c301e735c8ab5d 100755
--- a/tools/testing/selftests/net/forwarding/ethtool_mm.sh
+++ b/tools/testing/selftests/drivers/net/hw/ethtool_mm.sh
@@ -14,7 +14,8 @@ ALL_TESTS="
 NUM_NETIFS=2
 REQUIRE_MZ=no
 PREEMPTIBLE_PRIO=0
-source lib.sh
+lib_dir=$(dirname "$0")
+source "$lib_dir"/../../../net/forwarding/lib.sh
 
 traffic_test()
 {
diff --git a/tools/testing/selftests/net/forwarding/ethtool_rmon.sh b/tools/testing/selftests/drivers/net/hw/ethtool_rmon.sh
index 41a34a61f7632e..e2a1c10d35035c 100755
--- a/tools/testing/selftests/net/forwarding/ethtool_rmon.sh
+++ b/tools/testing/selftests/drivers/net/hw/ethtool_rmon.sh
@@ -7,7 +7,8 @@ ALL_TESTS="
 "
 
 NUM_NETIFS=2
-source lib.sh
+lib_dir=$(dirname "$0")
+source "$lib_dir"/../../../net/forwarding/lib.sh
 
 ETH_FCS_LEN=4
 ETH_HLEN=$((6+6+2))
@@ -78,7 +79,7 @@ rmon_histogram()
 
 		for if in $iface $neigh; do
 			if ! ensure_mtu $if ${bucket[0]}; then
-				log_test_skip "$if does not support the required MTU for $step"
+				log_test_xfail "$if does not support the required MTU for $step"
 				return
 			fi
 		done
@@ -93,7 +94,7 @@ rmon_histogram()
 		jq -r ".[0].rmon[\"${set}-pktsNtoM\"][]|[.low, .high]|@tsv" 2>/dev/null)
 
 	if [ $nbuckets -eq 0 ]; then
-		log_test_skip "$iface does not support $set histogram counters"
+		log_test_xfail "$iface does not support $set histogram counters"
 		return
 	fi
 }
diff --git a/tools/testing/selftests/net/forwarding/hw_stats_l3.sh b/tools/testing/selftests/drivers/net/hw/hw_stats_l3.sh
index 48584a51388fd9..7dfc50366c992e 100755
--- a/tools/testing/selftests/net/forwarding/hw_stats_l3.sh
+++ b/tools/testing/selftests/drivers/net/hw/hw_stats_l3.sh
@@ -48,7 +48,8 @@ ALL_TESTS="
 	test_double_enable
 "
 NUM_NETIFS=4
-source lib.sh
+lib_dir=$(dirname "$0")
+source "$lib_dir"/../../../net/forwarding/lib.sh
 
 h1_create()
 {
@@ -324,17 +325,9 @@ setup_wait
 
 used=$(ip -j stats show dev $rp1.200 group offload subgroup hw_stats_info |
 	   jq '.[].info.l3_stats.used')
-kind=$(ip -j -d link show dev $rp1 |
-	   jq -r '.[].linkinfo.info_kind')
-if [[ $used != true ]]; then
-	if [[ $kind == veth ]]; then
-		log_test_skip "l3_stats not offloaded on veth interface"
-		EXIT_STATUS=$ksft_skip
-	else
-		RET=1 log_test "l3_stats not offloaded"
-	fi
-else
-	tests_run
-fi
+[[ $used = true ]]
+check_err $? "hw_stats_info.used=$used"
+log_test "l3_stats offloaded"
+tests_run
 
 exit $EXIT_STATUS
diff --git a/tools/testing/selftests/net/forwarding/hw_stats_l3_gre.sh b/tools/testing/selftests/drivers/net/hw/hw_stats_l3_gre.sh
index 7594bbb4902923..ab8d04855af5c6 100755
--- a/tools/testing/selftests/net/forwarding/hw_stats_l3_gre.sh
+++ b/tools/testing/selftests/drivers/net/hw/hw_stats_l3_gre.sh
@@ -12,8 +12,9 @@ ALL_TESTS="
 	test_stats_tx
 "
 NUM_NETIFS=6
-source lib.sh
-source ipip_lib.sh
+lib_dir=$(dirname "$0")
+source "$lib_dir"/../../../net/forwarding/lib.sh
+source "$lib_dir"/../../../net/forwarding/ipip_lib.sh
 
 setup_prepare()
 {
@@ -99,8 +100,6 @@ test_stats_rx()
 	test_stats g2a rx
 }
 
-skip_on_veth
-
 trap cleanup EXIT
 
 setup_prepare
diff --git a/tools/testing/selftests/net/forwarding/loopback.sh b/tools/testing/selftests/drivers/net/hw/loopback.sh
index 8f4057310b5b41..5acc3ff820aa9e 100755
--- a/tools/testing/selftests/net/forwarding/loopback.sh
+++ b/tools/testing/selftests/drivers/net/hw/loopback.sh
@@ -6,8 +6,9 @@ ksft_skip=4
 
 ALL_TESTS="loopback_test"
 NUM_NETIFS=2
-source tc_common.sh
-source lib.sh
+lib_dir=$(dirname "$0")
+source "$lib_dir"/../../../net/forwarding/tc_common.sh
+source "$lib_dir"/../../../net/forwarding/lib.sh
 
 h1_create()
 {
diff --git a/tools/testing/selftests/drivers/net/hw/settings b/tools/testing/selftests/drivers/net/hw/settings
new file mode 100644
index 00000000000000..e7b9417537fbc4
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/hw/settings
@@ -0,0 +1 @@
+timeout=0
diff --git a/tools/testing/selftests/drivers/net/mlxsw/mlxsw_lib.sh b/tools/testing/selftests/drivers/net/mlxsw/mlxsw_lib.sh
index 6369927e9c378b..48395cfd4f9587 100644
--- a/tools/testing/selftests/drivers/net/mlxsw/mlxsw_lib.sh
+++ b/tools/testing/selftests/drivers/net/mlxsw/mlxsw_lib.sh
@@ -42,7 +42,7 @@ __mlxsw_only_on_spectrum()
 	local src=$1; shift
 
 	if ! mlxsw_on_spectrum "$rev"; then
-		log_test_skip $src:$caller "(Spectrum-$rev only)"
+		log_test_xfail $src:$caller "(Spectrum-$rev only)"
 		return 1
 	fi
 }
diff --git a/tools/testing/selftests/drivers/net/mlxsw/spectrum-2/resource_scale.sh b/tools/testing/selftests/drivers/net/mlxsw/spectrum-2/resource_scale.sh
index a88d8a8c85f2e0..899b6892603fd0 100755
--- a/tools/testing/selftests/drivers/net/mlxsw/spectrum-2/resource_scale.sh
+++ b/tools/testing/selftests/drivers/net/mlxsw/spectrum-2/resource_scale.sh
@@ -47,7 +47,6 @@ for current_test in ${TESTS:-$ALL_TESTS}; do
 		RET=0
 		target=$(${current_test}_get_target "$should_fail")
 		if ((target == 0)); then
-			log_test_skip "'$current_test' should_fail=$should_fail test"
 			continue
 		fi
 
diff --git a/tools/testing/selftests/drivers/net/mlxsw/spectrum/resource_scale.sh b/tools/testing/selftests/drivers/net/mlxsw/spectrum/resource_scale.sh
index f981c957f09759..482ebb744ebad8 100755
--- a/tools/testing/selftests/drivers/net/mlxsw/spectrum/resource_scale.sh
+++ b/tools/testing/selftests/drivers/net/mlxsw/spectrum/resource_scale.sh
@@ -52,7 +52,6 @@ for current_test in ${TESTS:-$ALL_TESTS}; do
 			RET=0
 			target=$(${current_test}_get_target "$should_fail")
 			if ((target == 0)); then
-				log_test_skip "'$current_test' [$profile] should_fail=$should_fail test"
 				continue
 			fi
 			${current_test}_setup_prepare
diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
index 7b6918d5f4afac..cb418a2346bc9e 100644
--- a/tools/testing/selftests/net/Makefile
+++ b/tools/testing/selftests/net/Makefile
@@ -20,7 +20,6 @@ TEST_PROGS += reuseaddr_ports_exhausted.sh
 TEST_PROGS += txtimestamp.sh
 TEST_PROGS += vrf-xfrm-tests.sh
 TEST_PROGS += rxtimestamp.sh
-TEST_PROGS += devlink_port_split.py
 TEST_PROGS += drop_monitor_tests.sh
 TEST_PROGS += vrf_route_leaking.sh
 TEST_PROGS += bareudp.sh
diff --git a/tools/testing/selftests/net/forwarding/Makefile b/tools/testing/selftests/net/forwarding/Makefile
index 535865b3d1d6cc..fa7b59ff40295a 100644
--- a/tools/testing/selftests/net/forwarding/Makefile
+++ b/tools/testing/selftests/net/forwarding/Makefile
@@ -15,18 +15,12 @@ TEST_PROGS = bridge_fdb_learning_limit.sh \
 	bridge_vlan_unaware.sh \
 	custom_multipath_hash.sh \
 	dual_vxlan_bridge.sh \
-	ethtool_extended_state.sh \
-	ethtool_mm.sh \
-	ethtool_rmon.sh \
-	ethtool.sh \
 	gre_custom_multipath_hash.sh \
 	gre_inner_v4_multipath.sh \
 	gre_inner_v6_multipath.sh \
 	gre_multipath_nh_res.sh \
 	gre_multipath_nh.sh \
 	gre_multipath.sh \
-	hw_stats_l3.sh \
-	hw_stats_l3_gre.sh \
 	ip6_forward_instats_vrf.sh \
 	ip6gre_custom_multipath_hash.sh \
 	ip6gre_flat_key.sh \
@@ -43,8 +37,8 @@ TEST_PROGS = bridge_fdb_learning_limit.sh \
 	ipip_hier_gre_key.sh \
 	ipip_hier_gre_keys.sh \
 	ipip_hier_gre.sh \
+	lib_sh_test.sh \
 	local_termination.sh \
-	loopback.sh \
 	mirror_gre_bound.sh \
 	mirror_gre_bridge_1d.sh \
 	mirror_gre_bridge_1d_vlan.sh \
@@ -113,7 +107,6 @@ TEST_PROGS = bridge_fdb_learning_limit.sh \
 	vxlan_symmetric.sh
 
 TEST_FILES := devlink_lib.sh \
-	ethtool_lib.sh \
 	fib_offload_lib.sh \
 	forwarding.config.sample \
 	ip6gre_lib.sh \
diff --git a/tools/testing/selftests/net/forwarding/README b/tools/testing/selftests/net/forwarding/README
index b8a2af8fcfb796..7fdb6a9ca543f1 100644
--- a/tools/testing/selftests/net/forwarding/README
+++ b/tools/testing/selftests/net/forwarding/README
@@ -56,3 +56,36 @@ o Checks shall be added to lib.sh for any external dependencies.
 o Code shall be checked using ShellCheck [1] prior to submission.
 
 1. https://www.shellcheck.net/
+
+Customization
+=============
+
+The forwarding selftests framework uses a number of variables that
+influence its behavior and tools it invokes, and how it invokes them, in
+various ways. A number of these variables can be overridden. The way these
+overridable variables are specified is typically one of the following two
+syntaxes:
+
+	: "${VARIABLE:=default_value}"
+	VARIABLE=${VARIABLE:=default_value}
+
+Any of these variables can be overridden. Notably net/forwarding/lib.sh and
+net/lib.sh contain a number of overridable variables.
+
+One way of overriding these variables is through the environment:
+
+	PAUSE_ON_FAIL=yes ./some_test.sh
+
+The variable NETIFS is special. Since it is an array variable, there is no
+way to pass it through the environment. Its value can instead be given as
+consecutive arguments to the selftest:
+
+	./some_test.sh swp{1..8}
+
+A way to customize variables in a persistent fashion is to create a file
+named forwarding.config in this directory. lib.sh sources the file if
+present, so it can contain any shell code. Typically it will contain
+assignments of variables whose value should be overridden.
+
+forwarding.config.sample is available in the directory as an example of
+how forwarding.config might look.
diff --git a/tools/testing/selftests/net/forwarding/forwarding.config.sample b/tools/testing/selftests/net/forwarding/forwarding.config.sample
index 1fc4f0242fc53b..f1ca95e79a65e8 100644
--- a/tools/testing/selftests/net/forwarding/forwarding.config.sample
+++ b/tools/testing/selftests/net/forwarding/forwarding.config.sample
@@ -3,51 +3,28 @@
 
 ##############################################################################
 # Topology description. p1 looped back to p2, p3 to p4 and so on.
-declare -A NETIFS
 
-NETIFS[p1]=veth0
-NETIFS[p2]=veth1
-NETIFS[p3]=veth2
-NETIFS[p4]=veth3
-NETIFS[p5]=veth4
-NETIFS[p6]=veth5
-NETIFS[p7]=veth6
-NETIFS[p8]=veth7
-NETIFS[p9]=veth8
-NETIFS[p10]=veth9
+NETIFS=(
+	[p1]=veth0
+	[p2]=veth1
+	[p3]=veth2
+	[p4]=veth3
+	[p5]=veth4
+	[p6]=veth5
+	[p7]=veth6
+	[p8]=veth7
+	[p9]=veth8
+	[p10]=veth9
+)
 
 # Port that does not have a cable connected.
 NETIF_NO_CABLE=eth8
 
 ##############################################################################
-# Defines
+# In addition to the topology-related variables, it is also possible to override
+# in this file other variables that net/lib.sh, net/forwarding/lib.sh or other
+# libraries or selftests use. E.g.:
 
-# IPv4 ping utility name
-PING=ping
-# IPv6 ping utility name. Some distributions use 'ping' for IPv6.
 PING6=ping6
-# Packet generator. Some distributions use 'mz'.
 MZ=mausezahn
-# mausezahn delay between transmissions in microseconds.
-MZ_DELAY=0
-# Time to wait after interfaces participating in the test are all UP
 WAIT_TIME=5
-# Whether to pause on failure or not.
-PAUSE_ON_FAIL=no
-# Whether to pause on cleanup or not.
-PAUSE_ON_CLEANUP=no
-# Type of network interface to create
-NETIF_TYPE=veth
-# Whether to create virtual interfaces (veth) or not
-NETIF_CREATE=yes
-# Timeout (in seconds) before ping exits regardless of how many packets have
-# been sent or received
-PING_TIMEOUT=5
-# Minimum ageing_time (in centiseconds) supported by hardware
-LOW_AGEING_TIME=1000
-# Flag for tc match, supposed to be skip_sw/skip_hw which means do not process
-# filter by software/hardware
-TC_FLAG=skip_hw
-# IPv6 traceroute utility name.
-TROUTE6=traceroute6
-
diff --git a/tools/testing/selftests/net/forwarding/ipip_lib.sh b/tools/testing/selftests/net/forwarding/ipip_lib.sh
index 30f36a57bae6c8..01e62c4ac94ddc 100644
--- a/tools/testing/selftests/net/forwarding/ipip_lib.sh
+++ b/tools/testing/selftests/net/forwarding/ipip_lib.sh
@@ -141,7 +141,6 @@
 # |               $h2 +       |
 # |     192.0.2.18/28         |
 # +---------------------------+
-source lib.sh
 
 h1_create()
 {
diff --git a/tools/testing/selftests/net/forwarding/lib.sh b/tools/testing/selftests/net/forwarding/lib.sh
index e579c2e0c462af..4103ed7afcde3d 100644
--- a/tools/testing/selftests/net/forwarding/lib.sh
+++ b/tools/testing/selftests/net/forwarding/lib.sh
@@ -2,33 +2,87 @@
 # SPDX-License-Identifier: GPL-2.0
 
 ##############################################################################
+# Topology description. p1 looped back to p2, p3 to p4 and so on.
+
+declare -A NETIFS=(
+    [p1]=veth0
+    [p2]=veth1
+    [p3]=veth2
+    [p4]=veth3
+    [p5]=veth4
+    [p6]=veth5
+    [p7]=veth6
+    [p8]=veth7
+    [p9]=veth8
+    [p10]=veth9
+)
+
+# Port that does not have a cable connected.
+: "${NETIF_NO_CABLE:=eth8}"
+
+##############################################################################
 # Defines
 
-# Can be overridden by the configuration file.
-PING=${PING:=ping}
-PING6=${PING6:=ping6}
-MZ=${MZ:=mausezahn}
-MZ_DELAY=${MZ_DELAY:=0}
-ARPING=${ARPING:=arping}
-TEAMD=${TEAMD:=teamd}
-WAIT_TIME=${WAIT_TIME:=5}
-PAUSE_ON_FAIL=${PAUSE_ON_FAIL:=no}
-PAUSE_ON_CLEANUP=${PAUSE_ON_CLEANUP:=no}
-NETIF_TYPE=${NETIF_TYPE:=veth}
-NETIF_CREATE=${NETIF_CREATE:=yes}
-MCD=${MCD:=smcrouted}
-MC_CLI=${MC_CLI:=smcroutectl}
-PING_COUNT=${PING_COUNT:=10}
-PING_TIMEOUT=${PING_TIMEOUT:=5}
-WAIT_TIMEOUT=${WAIT_TIMEOUT:=20}
-INTERFACE_TIMEOUT=${INTERFACE_TIMEOUT:=600}
-LOW_AGEING_TIME=${LOW_AGEING_TIME:=1000}
-REQUIRE_JQ=${REQUIRE_JQ:=yes}
-REQUIRE_MZ=${REQUIRE_MZ:=yes}
-REQUIRE_MTOOLS=${REQUIRE_MTOOLS:=no}
-STABLE_MAC_ADDRS=${STABLE_MAC_ADDRS:=no}
-TCPDUMP_EXTRA_FLAGS=${TCPDUMP_EXTRA_FLAGS:=}
-TROUTE6=${TROUTE6:=traceroute6}
+# Networking utilities.
+: "${PING:=ping}"
+: "${PING6:=ping6}"	# Some distros just use ping.
+: "${ARPING:=arping}"
+: "${TROUTE6:=traceroute6}"
+
+# Packet generator.
+: "${MZ:=mausezahn}"	# Some distributions use 'mz'.
+: "${MZ_DELAY:=0}"
+
+# Host configuration tools.
+: "${TEAMD:=teamd}"
+: "${MCD:=smcrouted}"
+: "${MC_CLI:=smcroutectl}"
+
+# Constants for netdevice bring-up:
+# Default time in seconds to wait for an interface to come up before giving up
+# and bailing out. Used during initial setup.
+: "${INTERFACE_TIMEOUT:=600}"
+# Like INTERFACE_TIMEOUT, but default for ad-hoc waiting in testing scripts.
+: "${WAIT_TIMEOUT:=20}"
+# Time to wait after interfaces participating in the test are all UP.
+: "${WAIT_TIME:=5}"
+
+# Whether to pause on, respectively, after a failure and before cleanup.
+: "${PAUSE_ON_FAIL:=no}"
+: "${PAUSE_ON_CLEANUP:=no}"
+
+# Whether to create virtual interfaces, and what netdevice type they should be.
+: "${NETIF_CREATE:=yes}"
+: "${NETIF_TYPE:=veth}"
+
+# Constants for ping tests:
+# How many packets should be sent.
+: "${PING_COUNT:=10}"
+# Timeout (in seconds) before ping exits regardless of how many packets have
+# been sent or received
+: "${PING_TIMEOUT:=5}"
+
+# Minimum ageing_time (in centiseconds) supported by hardware
+: "${LOW_AGEING_TIME:=1000}"
+
+# Whether to check for availability of certain tools.
+: "${REQUIRE_JQ:=yes}"
+: "${REQUIRE_MZ:=yes}"
+: "${REQUIRE_MTOOLS:=no}"
+
+# Whether to override MAC addresses on interfaces participating in the test.
+: "${STABLE_MAC_ADDRS:=no}"
+
+# Flags for tcpdump
+: "${TCPDUMP_EXTRA_FLAGS:=}"
+
+# Flags for TC filters.
+: "${TC_FLAG:=skip_hw}"
+
+# Whether the machine is "slow" -- i.e. might be incapable of running tests
+# involving heavy traffic. This might be the case on a debug kernel, a VM, or
+# e.g. a low-power board.
+: "${KSFT_MACHINE_SLOW:=no}"
 
 net_forwarding_dir=$(dirname "$(readlink -e "${BASH_SOURCE[0]}")")
 
@@ -205,17 +259,6 @@ check_port_mab_support()
 	fi
 }
 
-skip_on_veth()
-{
-	local kind=$(ip -j -d link show dev ${NETIFS[p1]} |
-		jq -r '.[].linkinfo.info_kind')
-
-	if [[ $kind == veth ]]; then
-		echo "SKIP: Test cannot be run with veth pairs"
-		exit $ksft_skip
-	fi
-}
-
 if [[ "$(id -u)" -ne 0 ]]; then
 	echo "SKIP: need root privileges"
 	exit $ksft_skip
@@ -358,14 +401,31 @@ EXIT_STATUS=0
 # Per-test return value. Clear at the beginning of each test.
 RET=0
 
+ret_set_ksft_status()
+{
+	local ksft_status=$1; shift
+	local msg=$1; shift
+
+	RET=$(ksft_status_merge $RET $ksft_status)
+	if (( $? )); then
+		retmsg=$msg
+	fi
+}
+
+# Whether FAILs should be interpreted as XFAILs. Internal.
+FAIL_TO_XFAIL=
+
 check_err()
 {
 	local err=$1
 	local msg=$2
 
-	if [[ $RET -eq 0 && $err -ne 0 ]]; then
-		RET=$err
-		retmsg=$msg
+	if ((err)); then
+		if [[ $FAIL_TO_XFAIL = yes ]]; then
+			ret_set_ksft_status $ksft_xfail "$msg"
+		else
+			ret_set_ksft_status $ksft_fail "$msg"
+		fi
 	fi
 }
 
@@ -374,10 +434,7 @@ check_fail()
 	local err=$1
 	local msg=$2
 
-	if [[ $RET -eq 0 && $err -eq 0 ]]; then
-		RET=1
-		retmsg=$msg
-	fi
+	check_err $((!err)) "$msg"
 }
 
 check_err_fail()
@@ -393,6 +450,85 @@ check_err_fail()
 	fi
 }
 
+xfail_on_slow()
+{
+	if [[ $KSFT_MACHINE_SLOW = yes ]]; then
+		FAIL_TO_XFAIL=yes "$@"
+	else
+		"$@"
+	fi
+}
+
+xfail_on_veth()
+{
+	local dev=$1; shift
+	local kind
+
+	kind=$(ip -j -d link show dev $dev |
+			jq -r '.[].linkinfo.info_kind')
+	if [[ $kind = veth ]]; then
+		FAIL_TO_XFAIL=yes "$@"
+	else
+		"$@"
+	fi
+}
+
+log_test_result()
+{
+	local test_name=$1; shift
+	local opt_str=$1; shift
+	local result=$1; shift
+	local retmsg=$1; shift
+
+	printf "TEST: %-60s  [%s]\n" "$test_name $opt_str" "$result"
+	if [[ $retmsg ]]; then
+		printf "\t%s\n" "$retmsg"
+	fi
+}
+
+pause_on_fail()
+{
+	if [[ $PAUSE_ON_FAIL == yes ]]; then
+		echo "Hit enter to continue, 'q' to quit"
+		read a
+		[[ $a == q ]] && exit 1
+	fi
+}
+
+handle_test_result_pass()
+{
+	local test_name=$1; shift
+	local opt_str=$1; shift
+
+	log_test_result "$test_name" "$opt_str" " OK "
+}
+
+handle_test_result_fail()
+{
+	local test_name=$1; shift
+	local opt_str=$1; shift
+
+	log_test_result "$test_name" "$opt_str" FAIL "$retmsg"
+	pause_on_fail
+}
+
+handle_test_result_xfail()
+{
+	local test_name=$1; shift
+	local opt_str=$1; shift
+
+	log_test_result "$test_name" "$opt_str" XFAIL "$retmsg"
+	pause_on_fail
+}
+
+handle_test_result_skip()
+{
+	local test_name=$1; shift
+	local opt_str=$1; shift
+
+	log_test_result "$test_name" "$opt_str" SKIP "$retmsg"
+}
+
 log_test()
 {
 	local test_name=$1
@@ -402,31 +538,28 @@ log_test()
 		opt_str="($opt_str)"
 	fi
 
-	if [[ $RET -ne 0 ]]; then
-		EXIT_STATUS=1
-		printf "TEST: %-60s  [FAIL]\n" "$test_name $opt_str"
-		if [[ ! -z "$retmsg" ]]; then
-			printf "\t%s\n" "$retmsg"
-		fi
-		if [ "${PAUSE_ON_FAIL}" = "yes" ]; then
-			echo "Hit enter to continue, 'q' to quit"
-			read a
-			[ "$a" = "q" ] && exit 1
-		fi
-		return 1
+	if ((RET == ksft_pass)); then
+		handle_test_result_pass "$test_name" "$opt_str"
+	elif ((RET == ksft_xfail)); then
+		handle_test_result_xfail "$test_name" "$opt_str"
+	elif ((RET == ksft_skip)); then
+		handle_test_result_skip "$test_name" "$opt_str"
+	else
+		handle_test_result_fail "$test_name" "$opt_str"
 	fi
 
-	printf "TEST: %-60s  [ OK ]\n" "$test_name $opt_str"
-	return 0
+	EXIT_STATUS=$(ksft_exit_status_merge $EXIT_STATUS $RET)
+	return $RET
 }
 
 log_test_skip()
 {
-	local test_name=$1
-	local opt_str=$2
+	RET=$ksft_skip retmsg= log_test "$@"
+}
 
-	printf "TEST: %-60s  [SKIP]\n" "$test_name $opt_str"
-	return 0
+log_test_xfail()
+{
+	RET=$ksft_xfail retmsg= log_test "$@"
 }
 
 log_info()
diff --git a/tools/testing/selftests/net/forwarding/lib_sh_test.sh b/tools/testing/selftests/net/forwarding/lib_sh_test.sh
new file mode 100755
index 00000000000000..ff2accccaf4d43
--- /dev/null
+++ b/tools/testing/selftests/net/forwarding/lib_sh_test.sh
@@ -0,0 +1,208 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+# This tests the operation of lib.sh itself.
+
+ALL_TESTS="
+	test_ret
+	test_exit_status
+"
+NUM_NETIFS=0
+source lib.sh
+
+# Simulated checks.
+
+do_test()
+{
+	local msg=$1; shift
+
+	"$@"
+	check_err $? "$msg"
+}
+
+tpass()
+{
+	do_test "tpass" true
+}
+
+tfail()
+{
+	do_test "tfail" false
+}
+
+txfail()
+{
+	FAIL_TO_XFAIL=yes do_test "txfail" false
+}
+
+# Simulated tests.
+
+pass()
+{
+	RET=0
+	do_test "true" true
+	log_test "true"
+}
+
+fail()
+{
+	RET=0
+	do_test "false" false
+	log_test "false"
+}
+
+xfail()
+{
+	RET=0
+	FAIL_TO_XFAIL=yes do_test "xfalse" false
+	log_test "xfalse"
+}
+
+skip()
+{
+	RET=0
+	log_test_skip "skip"
+}
+
+slow_xfail()
+{
+	RET=0
+	xfail_on_slow do_test "slow_false" false
+	log_test "slow_false"
+}
+
+# lib.sh tests.
+
+ret_tests_run()
+{
+	local t
+
+	RET=0
+	retmsg=
+	for t in "$@"; do
+		$t
+	done
+	echo "$retmsg"
+	return $RET
+}
+
+ret_subtest()
+{
+	local expect_ret=$1; shift
+	local expect_retmsg=$1; shift
+	local -a tests=( "$@" )
+
+	local status_names=(pass fail xfail xpass skip)
+	local ret
+	local out
+
+	RET=0
+
+	# Run this in a subshell, so that our environment is intact.
+	out=$(ret_tests_run "${tests[@]}")
+	ret=$?
+
+	(( ret == expect_ret ))
+	check_err $? "RET=$ret expected $expect_ret"
+
+	[[ $out == $expect_retmsg ]]
+	check_err $? "retmsg=$out expected $expect_retmsg"
+
+	log_test "RET $(echo ${tests[@]}) -> ${status_names[$ret]}"
+}
+
+test_ret()
+{
+	ret_subtest $ksft_pass ""
+
+	ret_subtest $ksft_pass "" tpass
+	ret_subtest $ksft_fail "tfail" tfail
+	ret_subtest $ksft_xfail "txfail" txfail
+
+	ret_subtest $ksft_pass "" tpass tpass
+	ret_subtest $ksft_fail "tfail" tpass tfail
+	ret_subtest $ksft_xfail "txfail" tpass txfail
+
+	ret_subtest $ksft_fail "tfail" tfail tpass
+	ret_subtest $ksft_xfail "txfail" txfail tpass
+
+	ret_subtest $ksft_fail "tfail" tfail tfail
+	ret_subtest $ksft_fail "tfail" tfail txfail
+
+	ret_subtest $ksft_fail "tfail" txfail tfail
+
+	ret_subtest $ksft_xfail "txfail" txfail txfail
+}
+
+exit_status_tests_run()
+{
+	EXIT_STATUS=0
+	tests_run > /dev/null
+	return $EXIT_STATUS
+}
+
+exit_status_subtest()
+{
+	local expect_exit_status=$1; shift
+	local tests=$1; shift
+	local what=$1; shift
+
+	local status_names=(pass fail xfail xpass skip)
+	local exit_status
+	local out
+
+	RET=0
+
+	# Run this in a subshell, so that our environment is intact.
+	out=$(TESTS="$tests" exit_status_tests_run)
+	exit_status=$?
+
+	(( exit_status == expect_exit_status ))
+	check_err $? "EXIT_STATUS=$exit_status, expected $expect_exit_status"
+
+	log_test "EXIT_STATUS $tests$what -> ${status_names[$exit_status]}"
+}
+
+test_exit_status()
+{
+	exit_status_subtest $ksft_pass ":"
+
+	exit_status_subtest $ksft_pass "pass"
+	exit_status_subtest $ksft_fail "fail"
+	exit_status_subtest $ksft_pass "xfail"
+	exit_status_subtest $ksft_skip "skip"
+
+	exit_status_subtest $ksft_pass "pass pass"
+	exit_status_subtest $ksft_fail "pass fail"
+	exit_status_subtest $ksft_pass "pass xfail"
+	exit_status_subtest $ksft_skip "pass skip"
+
+	exit_status_subtest $ksft_fail "fail pass"
+	exit_status_subtest $ksft_pass "xfail pass"
+	exit_status_subtest $ksft_skip "skip pass"
+
+	exit_status_subtest $ksft_fail "fail fail"
+	exit_status_subtest $ksft_fail "fail xfail"
+	exit_status_subtest $ksft_fail "fail skip"
+
+	exit_status_subtest $ksft_fail "xfail fail"
+	exit_status_subtest $ksft_fail "skip fail"
+
+	exit_status_subtest $ksft_pass "xfail xfail"
+	exit_status_subtest $ksft_skip "xfail skip"
+	exit_status_subtest $ksft_skip "skip xfail"
+
+	exit_status_subtest $ksft_skip "skip skip"
+
+	KSFT_MACHINE_SLOW=yes \
+		exit_status_subtest $ksft_pass "slow_xfail" ": slow"
+
+	KSFT_MACHINE_SLOW=no \
+		exit_status_subtest $ksft_fail "slow_xfail" ": fast"
+}
+
+trap pre_cleanup EXIT
+
+tests_run
+
+exit $EXIT_STATUS
diff --git a/tools/testing/selftests/net/forwarding/router_mpath_nh_lib.sh b/tools/testing/selftests/net/forwarding/router_mpath_nh_lib.sh
index 7e7d62161c345a..2903294d8bca0c 100644
--- a/tools/testing/selftests/net/forwarding/router_mpath_nh_lib.sh
+++ b/tools/testing/selftests/net/forwarding/router_mpath_nh_lib.sh
@@ -56,21 +56,12 @@ nh_stats_test_dispatch_swhw()
 	local group_id=$1; shift
 	local mz="$@"
 
-	local used
-
 	nh_stats_do_test "$what" "$nh1_id" "$nh2_id" "$group_id" \
 			 nh_stats_get "${mz[@]}"
 
-	used=$(ip -s -j -d nexthop show id $group_id |
-		   jq '.[].hw_stats.used')
-	kind=$(ip -j -d link show dev $rp11 |
-		   jq -r '.[].linkinfo.info_kind')
-	if [[ $used == true ]]; then
+	xfail_on_veth $rp11 \
 		nh_stats_do_test "HW $what" "$nh1_id" "$nh2_id" "$group_id" \
 				 nh_stats_get_hw "${mz[@]}"
-	elif [[ $kind == veth ]]; then
-		log_test_skip "HW stats not offloaded on veth topology"
-	fi
 }
 
 nh_stats_test_dispatch()
@@ -83,7 +74,6 @@ nh_stats_test_dispatch()
 	local mz="$@"
 
 	local enabled
-	local kind
 
 	if ! ip nexthop help 2>&1 | grep -q hw_stats; then
 		log_test_skip "NH stats test: ip doesn't support HW stats"
diff --git a/tools/testing/selftests/net/forwarding/sch_ets_tests.sh b/tools/testing/selftests/net/forwarding/sch_ets_tests.sh
index cdf689e99458e0..f9d26a7911bb7b 100644
--- a/tools/testing/selftests/net/forwarding/sch_ets_tests.sh
+++ b/tools/testing/selftests/net/forwarding/sch_ets_tests.sh
@@ -199,25 +199,28 @@ ets_set_dwrr_two_bands()
 ets_test_strict()
 {
 	ets_set_strict
-	ets_dwrr_test_01
-	ets_dwrr_test_12
+	xfail_on_slow ets_dwrr_test_01
+	xfail_on_slow ets_dwrr_test_12
 }
 
 ets_test_mixed()
 {
 	ets_set_mixed
-	ets_dwrr_test_01
-	ets_dwrr_test_12
+	xfail_on_slow ets_dwrr_test_01
+	xfail_on_slow ets_dwrr_test_12
 }
 
 ets_test_dwrr()
 {
 	ets_set_dwrr_uniform
-	ets_dwrr_test_012
+	xfail_on_slow ets_dwrr_test_012
+
 	ets_set_dwrr_varying
-	ets_dwrr_test_012
+	xfail_on_slow ets_dwrr_test_012
+
 	ets_change_quantum
-	ets_dwrr_test_012
+	xfail_on_slow ets_dwrr_test_012
+
 	ets_set_dwrr_two_bands
-	ets_dwrr_test_01
+	xfail_on_slow ets_dwrr_test_01
 }
diff --git a/tools/testing/selftests/net/forwarding/sch_red.sh b/tools/testing/selftests/net/forwarding/sch_red.sh
index 81f31179ac8878..17f28644568eba 100755
--- a/tools/testing/selftests/net/forwarding/sch_red.sh
+++ b/tools/testing/selftests/net/forwarding/sch_red.sh
@@ -451,35 +451,35 @@ uninstall_qdisc()
 ecn_test()
 {
 	install_qdisc ecn
-	do_ecn_test $BACKLOG
+	xfail_on_slow do_ecn_test $BACKLOG
 	uninstall_qdisc
 }
 
 ecn_nodrop_test()
 {
 	install_qdisc ecn nodrop
-	do_ecn_nodrop_test $BACKLOG
+	xfail_on_slow do_ecn_nodrop_test $BACKLOG
 	uninstall_qdisc
 }
 
 red_test()
 {
 	install_qdisc
-	do_red_test $BACKLOG
+	xfail_on_slow do_red_test $BACKLOG
 	uninstall_qdisc
 }
 
 red_qevent_test()
 {
 	install_qdisc qevent early_drop block 10
-	do_red_qevent_test $BACKLOG
+	xfail_on_slow do_red_qevent_test $BACKLOG
 	uninstall_qdisc
 }
 
 ecn_qevent_test()
 {
 	install_qdisc ecn qevent mark block 10
-	do_ecn_qevent_test $BACKLOG
+	xfail_on_slow do_ecn_qevent_test $BACKLOG
 	uninstall_qdisc
 }
 
diff --git a/tools/testing/selftests/net/forwarding/sch_tbf_core.sh b/tools/testing/selftests/net/forwarding/sch_tbf_core.sh
index d1f26cb7cd73b7..9cd884d4a5dec1 100644
--- a/tools/testing/selftests/net/forwarding/sch_tbf_core.sh
+++ b/tools/testing/selftests/net/forwarding/sch_tbf_core.sh
@@ -227,7 +227,7 @@ do_tbf_test()
 	local nr=$(rate $t2 $t3 10)
 	local nr_pct=$((100 * (nr - er) / er))
 	((-5 <= nr_pct && nr_pct <= 5))
-	check_err $? "Expected rate $(humanize $er), got $(humanize $nr), which is $nr_pct% off. Required accuracy is +-5%."
+	xfail_on_slow check_err $? "Expected rate $(humanize $er), got $(humanize $nr), which is $nr_pct% off. Required accuracy is +-5%."
 
 	log_test "TC $((vlan - 10)): TBF rate ${mbit}Mbit"
 }
diff --git a/tools/testing/selftests/net/forwarding/tc_common.sh b/tools/testing/selftests/net/forwarding/tc_common.sh
index bce8bb8d2b6f3c..2e3326edfa9a01 100644
--- a/tools/testing/selftests/net/forwarding/tc_common.sh
+++ b/tools/testing/selftests/net/forwarding/tc_common.sh
@@ -4,7 +4,7 @@
 CHECK_TC="yes"
 
 # Can be overridden by the configuration file. See lib.sh
-TC_HIT_TIMEOUT=${TC_HIT_TIMEOUT:=1000} # ms
+: "${TC_HIT_TIMEOUT:=1000}" # ms
 
 tc_check_packets()
 {
diff --git a/tools/testing/selftests/net/forwarding/tc_tunnel_key.sh b/tools/testing/selftests/net/forwarding/tc_tunnel_key.sh
index 5a5dd90348195c..79775b10b99f1e 100755
--- a/tools/testing/selftests/net/forwarding/tc_tunnel_key.sh
+++ b/tools/testing/selftests/net/forwarding/tc_tunnel_key.sh
@@ -1,7 +1,5 @@
 #!/bin/bash
 # SPDX-License-Identifier: GPL-2.0
-# Kselftest framework requirement - SKIP code is 4.
-ksft_skip=4
 
 ALL_TESTS="tunnel_key_nofrag_test"
 
diff --git a/tools/testing/selftests/net/lib.sh b/tools/testing/selftests/net/lib.sh
index f9fe182dfbd44e..b7f7b8695165b4 100644
--- a/tools/testing/selftests/net/lib.sh
+++ b/tools/testing/selftests/net/lib.sh
@@ -4,16 +4,60 @@
 ##############################################################################
 # Defines
 
-WAIT_TIMEOUT=${WAIT_TIMEOUT:=20}
+: "${WAIT_TIMEOUT:=20}"
+
 BUSYWAIT_TIMEOUT=$((WAIT_TIMEOUT * 1000)) # ms
 
-# Kselftest framework requirement - SKIP code is 4.
+# Kselftest framework constants.
+ksft_pass=0
+ksft_fail=1
+ksft_xfail=2
 ksft_skip=4
+
 # namespace list created by setup_ns
 NS_LIST=""
 
 ##############################################################################
 # Helpers
+
+__ksft_status_merge()
+{
+	local a=$1; shift
+	local b=$1; shift
+	local -A weights
+	local weight=0
+
+	for i in "$@"; do
+		weights[$i]=$((weight++))
+	done
+
+	if [[ ${weights[$a]} > ${weights[$b]} ]]; then
+		echo "$a"
+		return 0
+	else
+		echo "$b"
+		return 1
+	fi
+}
+
+ksft_status_merge()
+{
+	local a=$1; shift
+	local b=$1; shift
+
+	__ksft_status_merge "$a" "$b" \
+		$ksft_pass $ksft_xfail $ksft_skip $ksft_fail
+}
+
+ksft_exit_status_merge()
+{
+	local a=$1; shift
+	local b=$1; shift
+
+	__ksft_status_merge "$a" "$b" \
+		$ksft_xfail $ksft_pass $ksft_skip $ksft_fail
+}
+
 busywait()
 {
 	local timeout=$1; shift