[PATCH net-next v2] selftests: net: local_termination: annotate the expected failures

[Jakub Kicinski <kuba@xxxxxxxxxx>]

Vladimir said when adding this test:

  The bridge driver fares particularly badly [...] mainly because
  it does not implement IFF_UNICAST_FLT.

See commit 90b9566aa5cd ("selftests: forwarding: add a test for
local_termination.sh").

We don't want to hide the known gaps, but having a test which
always fails prevents us from catching regressions. Report
the cases we know may fail as XFAIL.

Reviewed-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
Tested-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
---
CC: liuhangbin@xxxxxxxxx
CC: shuah@xxxxxxxxxx
CC: linux-kselftest@xxxxxxxxxxxxxxx

v2:
 - remove duplicated log_test_xfail
v1: https://lore.kernel.org/all/20240509235553.5740-1-kuba@xxxxxxxxxx/
---
 .../net/forwarding/local_termination.sh       | 21 ++++++++++++++-----
 1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/tools/testing/selftests/net/forwarding/local_termination.sh b/tools/testing/selftests/net/forwarding/local_termination.sh
index c5b0cbc85b3e..4bba9c78db3e 100755
--- a/tools/testing/selftests/net/forwarding/local_termination.sh
+++ b/tools/testing/selftests/net/forwarding/local_termination.sh
@@ -73,6 +73,10 @@ check_rcv()
 	local pattern=$3
 	local should_receive=$4
 	local should_fail=
+	local xfail_sw=$5
+
+	local kind=$(ip -j -d link show dev $if_name |
+			 jq -r '.[].linkinfo.info_kind')
 
 	[ $should_receive = true ] && should_fail=0 || should_fail=1
 	RET=0
@@ -81,7 +85,14 @@ check_rcv()
 
 	check_err_fail "$should_fail" "$?" "reception"
 
-	log_test "$if_name: $type"
+	# If not a SW interface, ignore the XFAIL allowance
+	[ "$kind" != veth ] && [ "$kind" != bridge ] && xfail_sw=
+
+	if [ $RET -ne 0 ] && [ "$xfail_sw" == true ]; then
+	    log_test_xfail "$if_name: $type"
+	else
+	    log_test "$if_name: $type"
+	fi
 }
 
 mc_route_prepare()
@@ -157,7 +168,7 @@ run_test()
 
 	check_rcv $rcv_if_name "Unicast IPv4 to unknown MAC address" \
 		"$smac > $UNKNOWN_UC_ADDR1, ethertype IPv4 (0x0800)" \
-		false
+		false true
 
 	check_rcv $rcv_if_name "Unicast IPv4 to unknown MAC address, promisc" \
 		"$smac > $UNKNOWN_UC_ADDR2, ethertype IPv4 (0x0800)" \
@@ -165,7 +176,7 @@ run_test()
 
 	check_rcv $rcv_if_name "Unicast IPv4 to unknown MAC address, allmulti" \
 		"$smac > $UNKNOWN_UC_ADDR3, ethertype IPv4 (0x0800)" \
-		false
+		false true
 
 	check_rcv $rcv_if_name "Multicast IPv4 to joined group" \
 		"$smac > $JOINED_MACV4_MC_ADDR, ethertype IPv4 (0x0800)" \
@@ -173,7 +184,7 @@ run_test()
 
 	check_rcv $rcv_if_name "Multicast IPv4 to unknown group" \
 		"$smac > $UNKNOWN_MACV4_MC_ADDR1, ethertype IPv4 (0x0800)" \
-		false
+		false true
 
 	check_rcv $rcv_if_name "Multicast IPv4 to unknown group, promisc" \
 		"$smac > $UNKNOWN_MACV4_MC_ADDR2, ethertype IPv4 (0x0800)" \
@@ -189,7 +200,7 @@ run_test()
 
 	check_rcv $rcv_if_name "Multicast IPv6 to unknown group" \
 		"$smac > $UNKNOWN_MACV6_MC_ADDR1, ethertype IPv6 (0x86dd)" \
-		false
+		false true
 
 	check_rcv $rcv_if_name "Multicast IPv6 to unknown group, promisc" \
 		"$smac > $UNKNOWN_MACV6_MC_ADDR2, ethertype IPv6 (0x86dd)" \
-- 
2.45.0