[PATCH net-next] selftests: net: add ipv6 RA route to ECMP merge test

[PATCH net-next] selftests: net: add ipv6 RA route to ECMP merge test

[Fernando Fernandez Mancera]

As commit bbf4a17ad9ff ("ipv6: Fix ECMP sibling count mismatch when
clearing RTF_ADDRCONF") pointed out, RA routes are not elegible for ECMP
merging.

Add a test scenario mixing RA and static routes with gateway to check
that they are not getting merged.

Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
---
 tools/testing/selftests/net/fib_tests.sh | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/tools/testing/selftests/net/fib_tests.sh b/tools/testing/selftests/net/fib_tests.sh
index c5694cc4ddd2..1262ee1ea09b 100755
--- a/tools/testing/selftests/net/fib_tests.sh
+++ b/tools/testing/selftests/net/fib_tests.sh
@@ -1534,6 +1534,23 @@ fib6_ra_to_static()
 
 	log_test $ret 0 "ipv6 promote RA route to static"
 
+	# Prepare for RA route with gateway
+	$NS_EXEC sysctl -wq net.ipv6.conf.veth1.accept_ra_rt_info_max_plen=64
+
+	# Add initial route to cause ECMP merging
+	$IP -6 route add 2001:12::/64 via fe80::dead:beef dev veth1
+
+	$NS_EXEC ra6 -i veth2 -d 2001:10::1 -R 2001:12::/64#1#120
+
+	# Routes are not merged as RA routes are not elegible for ECMP
+	check_rt_num 2 "$($IP -6 route list | grep -c "2001:12::/64 via")"
+
+	$IP -6 route append 2001:12::/64 via fe80::dead:feeb dev veth1
+
+	check_rt_num 2 "$($IP -6 route list | grep -c "nexthop via")"
+
+	log_test "$ret" 0 "ipv6 RA route with nexthop do not merge into ECMP with static"
+
 	set +e
 
 	cleanup &> /dev/null
-- 
2.53.0

Re: [PATCH net-next] selftests: net: add ipv6 RA route to ECMP merge test

[Jakub Kicinski]

On Mon, 23 Feb 2026 16:09:50 +0100 Fernando Fernandez Mancera wrote:
> +	# Prepare for RA route with gateway
> +	$NS_EXEC sysctl -wq net.ipv6.conf.veth1.accept_ra_rt_info_max_plen=64

This fails for us:

# 95.85 [+2.11]     TEST: ipv6 promote RA route to static                               [ OK ]
# 95.85 [+0.01] sysctl: cannot stat /proc/sys/net/ipv6/conf/veth1/accept_ra_rt_info_max_plen: No such file or directory
not ok 1 selftests: net: fib_tests.sh # exit=1

https://netdev-ctrl.bots.linux.dev/logs/vmksft/net/results/531161/10-fib-tests-sh/stdout
-- 
pw-bot: cr

Re: [PATCH net-next] selftests: net: add ipv6 RA route to ECMP merge test

[Fernando Fernandez Mancera]

On 2/23/26 7:39 PM, Jakub Kicinski wrote:
> On Mon, 23 Feb 2026 16:09:50 +0100 Fernando Fernandez Mancera wrote:
>> +	# Prepare for RA route with gateway
>> +	$NS_EXEC sysctl -wq net.ipv6.conf.veth1.accept_ra_rt_info_max_plen=64
> 
> This fails for us:
> 
> # 95.85 [+2.11]     TEST: ipv6 promote RA route to static                               [ OK ]
> # 95.85 [+0.01] sysctl: cannot stat /proc/sys/net/ipv6/conf/veth1/accept_ra_rt_info_max_plen: No such file or directory
> not ok 1 selftests: net: fib_tests.sh # exit=1
> 
> https://netdev-ctrl.bots.linux.dev/logs/vmksft/net/results/531161/10-fib-tests-sh/stdout

Hm, I see. CONFIG_IPV6_ROUTE_INFO seems to be missing. I am adjusting it.

Thanks,
Fernando.