cmsg_ipv6 test requests tcpdump to capture 4 packets, and sends until tcpdump quits. Only the first packet is "real", however, and the rest are basic UDP packets. So if tcpdump doesn't start in time it will miss the real packet and only capture the UDP ones. This makes the test fail on slow machine (no KVM or with debug enabled) 100% of the time, while it passes in fast environments. Repeat the "real" / expected packet. Fixes: 9657ad09e1fa ("selftests: net: test IPV6_TCLASS") Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> --- CC: shuah@xxxxxxxxxx CC: linux-kselftest@xxxxxxxxxxxxxxx --- tools/testing/selftests/net/cmsg_ipv6.sh | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/net/cmsg_ipv6.sh b/tools/testing/selftests/net/cmsg_ipv6.sh index f30bd57d5e38..8bc23fb4c82b 100755 --- a/tools/testing/selftests/net/cmsg_ipv6.sh +++ b/tools/testing/selftests/net/cmsg_ipv6.sh @@ -89,7 +89,7 @@ for ovr in setsock cmsg both diff; do check_result $? 0 "TCLASS $prot $ovr - pass" while [ -d /proc/$BG ]; do - $NSEXE ./cmsg_sender -6 -p u $TGT6 1234 + $NSEXE ./cmsg_sender -6 -p $p $m $((TOS2)) $TGT6 1234 done tcpdump -r $TMPF -v 2>&1 | grep "class $TOS2" >> /dev/null @@ -126,7 +126,7 @@ for ovr in setsock cmsg both diff; do check_result $? 0 "HOPLIMIT $prot $ovr - pass" while [ -d /proc/$BG ]; do - $NSEXE ./cmsg_sender -6 -p u $TGT6 1234 + $NSEXE ./cmsg_sender -6 -p $p $m $LIM $TGT6 1234 done tcpdump -r $TMPF -v 2>&1 | grep "hlim $LIM[^0-9]" >> /dev/null -- 2.43.0