Several forwarding tests (e.g., gre_multipath.sh) initialize both IPv4
and IPv6 addresses using simple_if_init, but only clean up IPv4
in simple_if_fini. This leaves stale IPv6 addresses on the interfaces,
which causes subsequent tests to fail when they encounter unexpected
address configuration.
The issue can be reproduced by running tests in sequence:
# run_kselftest.sh -t net/forwarding:ipip_hier_gre.sh
# run_kselftest.sh -t net/forwarding:min_max_mtu.sh
TAP version 13
1..1
# timeout set to 0
# selftests: net/forwarding: min_max_mtu.sh
# TEST: ping [ OK ]
# TEST: ping6 [ OK ]
# TEST: Test maximum MTU configuration [ OK ]
# TEST: Test traffic, packet size is maximum MTU [FAIL]
# Ping6, packet size: 65487 succeeded, but should have failed
# TEST: Test minimum MTU configuration [ OK ]
# TEST: Test traffic, packet size is minimum MTU [ OK ]
not ok 1 selftests: net/forwarding: min_max_mtu.sh # exit=1
Fix this by removing the unused IPv6 argument from simple_if_init in
tests that don't use IPv6 (gre_multipath.sh, ipip_lib.sh), and by
adding the missing IPv6 argument to simple_if_fini in tests that
use IPv6 (gre_multipath_nh.sh, gre_multipath_nh_res.sh).
Signed-off-by: Aleksei Oladko <aleksey.oladko@virtuozzo.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260305211000.515301-1-aleksey.oladko@virtuozzo.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
21c0dc7cdd