From: Guillaume Nault gnault@redhat.com
[ Upstream commit 18dfc667550fe9c032a6dcc3402b50e691e18029 ]
The cleanup() function takes care of killing processes launched by the test functions. It relies on variables like ${tcpdump_pids} to get the relevant PIDs. But tests are run in their own subshell, so updated *_pids values are invisible to other shells. Therefore cleanup() never sees any process to kill:
$ ./tools/testing/selftests/net/pmtu.sh -t pmtu_ipv4_exception TEST: ipv4: PMTU exceptions [ OK ] TEST: ipv4: PMTU exceptions - nexthop objects [ OK ]
$ pgrep -af tcpdump 6084 tcpdump -s 0 -i veth_A-R1 -w pmtu_ipv4_exception_veth_A-R1.pcap 6085 tcpdump -s 0 -i veth_R1-A -w pmtu_ipv4_exception_veth_R1-A.pcap 6086 tcpdump -s 0 -i veth_R1-B -w pmtu_ipv4_exception_veth_R1-B.pcap 6087 tcpdump -s 0 -i veth_B-R1 -w pmtu_ipv4_exception_veth_B-R1.pcap 6088 tcpdump -s 0 -i veth_A-R2 -w pmtu_ipv4_exception_veth_A-R2.pcap 6089 tcpdump -s 0 -i veth_R2-A -w pmtu_ipv4_exception_veth_R2-A.pcap 6090 tcpdump -s 0 -i veth_R2-B -w pmtu_ipv4_exception_veth_R2-B.pcap 6091 tcpdump -s 0 -i veth_B-R2 -w pmtu_ipv4_exception_veth_B-R2.pcap 6228 tcpdump -s 0 -i veth_A-R1 -w pmtu_ipv4_exception_veth_A-R1.pcap 6229 tcpdump -s 0 -i veth_R1-A -w pmtu_ipv4_exception_veth_R1-A.pcap 6230 tcpdump -s 0 -i veth_R1-B -w pmtu_ipv4_exception_veth_R1-B.pcap 6231 tcpdump -s 0 -i veth_B-R1 -w pmtu_ipv4_exception_veth_B-R1.pcap 6232 tcpdump -s 0 -i veth_A-R2 -w pmtu_ipv4_exception_veth_A-R2.pcap 6233 tcpdump -s 0 -i veth_R2-A -w pmtu_ipv4_exception_veth_R2-A.pcap 6234 tcpdump -s 0 -i veth_R2-B -w pmtu_ipv4_exception_veth_R2-B.pcap 6235 tcpdump -s 0 -i veth_B-R2 -w pmtu_ipv4_exception_veth_B-R2.pcap
Fix this by running cleanup() in the context of the test subshell. Now that each test cleans the environment after completion, there's no need for calling cleanup() again when the next test starts. So let's drop it from the setup() function. This is okay because cleanup() is also called when pmtu.sh starts, so even the first test starts in a clean environment.
Also, use tcpdump's immediate mode. Otherwise it might not have time to process buffered packets, resulting in missing packets or even empty pcap files for short tests.
Note: PAUSE_ON_FAIL is still evaluated before cleanup(), so one can still inspect the test environment upon failure when using -p.
Fixes: a92a0a7b8e7c ("selftests: pmtu: Simplify cleanup and namespace names") Signed-off-by: Guillaume Nault gnault@redhat.com Reviewed-by: Shuah Khan skhan@linuxfoundation.org Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- tools/testing/selftests/net/pmtu.sh | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/net/pmtu.sh b/tools/testing/selftests/net/pmtu.sh index 3429767cadcd..88be9083b923 100755 --- a/tools/testing/selftests/net/pmtu.sh +++ b/tools/testing/selftests/net/pmtu.sh @@ -579,7 +579,6 @@ setup_routing() { setup() { [ "$(id -u)" -ne 0 ] && echo " need to run as root" && return $ksft_skip
- cleanup for arg do eval setup_${arg} || { echo " ${arg} not supported"; return 1; } done @@ -590,7 +589,7 @@ trace() {
for arg do [ "${ns_cmd}" = "" ] && ns_cmd="${arg}" && continue - ${ns_cmd} tcpdump -s 0 -i "${arg}" -w "${name}_${arg}.pcap" 2> /dev/null & + ${ns_cmd} tcpdump --immediate-mode -s 0 -i "${arg}" -w "${name}_${arg}.pcap" 2> /dev/null & tcpdump_pids="${tcpdump_pids} $!" ns_cmd= done @@ -1182,6 +1181,10 @@ run_test() {
unset IFS
+ # Since cleanup() relies on variables modified by this subshell, it + # has to run in this context. + trap cleanup EXIT + if [ "$VERBOSE" = "1" ]; then printf "\n##########################################################################\n\n" fi