Seems to be a block on network on __skb_wait_for_more_packets
$cat /proc/3833/wchan __skb_wait_for_more_packets
From strace POV that is a wait in accept that does not unblock:
$ sudo strace -rT -p 3833 strace: Process 3833 attached 0.000000 accept(6, NULL, NULL <hangs>
The logs are no help: /tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-stderr => empty /tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-stdout => matches the console
$ cat /tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-stdout make: Entering directory '/tmp/autopkgtest.epy1pq/autopkgtest_tmp' cc -O2 -Wall -g -fPIC -c -o client.o client.c cc -O2 -Wall -g -fPIC -shared -o clknetsim.so client.o -ldl -lm g++ -O2 -Wall -g -fPIC -c -o clock.o clock.cc g++ -O2 -Wall -g -fPIC -c -o node.o node.cc g++ -O2 -Wall -g -fPIC -c -o generator.o generator.cc g++ -O2 -Wall -g -fPIC -c -o network.o network.cc g++ -O2 -Wall -g -fPIC -c -o server.o server.cc g++ -O2 -Wall -g -fPIC -c -o stats.o stats.cc g++ -O2 -Wall -g -fPIC -o clknetsim clock.o node.o generator.o network.o server.o stats.o make: Leaving directory '/tmp/autopkgtest.epy1pq/autopkgtest_tmp' 001-defaults <hang>
Noisy PS output:
4 0 506 1 20 0 2600 1920 - Ss ttyS1 0:00 /bin/sh 1 0 3690 506 20 0 2600 128 - S+ ttyS1 0:00 \_ /bin/sh 4 0 3691 3690 20 0 8172 3660 - S+ ttyS1 0:00 \_ su -s /bin/bash ubuntu -c set -e; export USER=`id -nu`; . /etc/profile >/dev/null 2>&1 || true; . ~/.profile >/dev/null 2>&1 || true; buildtree="/tmp/autopkgtest.epy1pq/build.KhE/src"; mkdir -p -m 1777 -- "/tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-artifacts"; export AUTOPKGTEST_ARTIFA CTS="/tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-artifacts"; export ADT_ARTIFACTS="$AUTOPKGTEST_ARTIFACTS"; mkdir -p -m 755 "/tmp/autopkgtest.epy1pq/autopkgtest_tmp"; export AUTOP KGTEST_TMP="/tmp/autopkgtest.epy1pq/autopkgtest_tmp"; export ADTTMP="$AUTOPKGTEST_TMP"; export DEBIAN_FRONTEND=noninteractive; export LANG=C.UTF-8; export DEB_BUILD_OPTIONS=parallel=2; unset LANGUAGE LC_CTYPE LC_NUMERIC LC_TIME LC_COLLATE LC_MONETARY LC_MESSAGES LC_PAPER LC_NAME LC_ADDRESS LC_TELEPHONE LC_MEASUREMENT LC_IDENTIFICATION LC_ALL;rm -f /tmp/autopkgtest_script_pi d; set -C; echo $$ > /tmp/autopkgtest_script_pid; set +C; trap "rm -f /tmp/autopkgtest_script_pid" EXIT INT QUIT PIPE; cd "$buildtree"; chmod +x /tmp/autopkgtest.epy1pq/build.KhE/src/debian/ tests/upstream-simulation-test-suite; touch /tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-stdout /tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-stderr; /tmp/autopkgtest.epy1 pq/build.KhE/src/debian/tests/upstream-simulation-test-suite 2> >(tee -a /tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-stderr >&2) > >(tee -a /tmp/autopkgtest.epy1pq/upstream-simula tion-test-suite-stdout); 4 1000 3720 3691 20 0 8608 3852 do_wai Ss ? 0:00 \_ bash -c set -e; export USER=`id -nu`; . /etc/profile >/dev/null 2>&1 || true; . ~/.profile >/dev/null 2> &1 || true; buildtree="/tmp/autopkgtest.epy1pq/build.KhE/src"; mkdir -p -m 1777 -- "/tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-artifacts"; export AUTOPKGTEST_ARTIFACTS="/tmp/auto pkgtest.epy1pq/upstream-simulation-test-suite-artifacts"; export ADT_ARTIFACTS="$AUTOPKGTEST_ARTIFACTS"; mkdir -p -m 755 "/tmp/autopkgtest.epy1pq/autopkgtest_tmp"; export AUTOPKGTEST_TMP="/t mp/autopkgtest.epy1pq/autopkgtest_tmp"; export ADTTMP="$AUTOPKGTEST_TMP"; export DEBIAN_FRONTEND=noninteractive; export LANG=C.UTF-8; export DEB_BUILD_OPTIONS=parallel=2; unset LANGUAGE LC_C TYPE LC_NUMERIC LC_TIME LC_COLLATE LC_MONETARY LC_MESSAGES LC_PAPER LC_NAME LC_ADDRESS LC_TELEPHONE LC_MEASUREMENT LC_IDENTIFICATION LC_ALL;rm -f /tmp/autopkgtest_script_pid; set -C; ech o $$ > /tmp/autopkgtest_script_pid; set +C; trap "rm -f /tmp/autopkgtest_script_pid" EXIT INT QUIT PIPE; cd "$buildtree"; chmod +x /tmp/autopkgtest.epy1pq/build.KhE/src/debian/tests/upstream -simulation-test-suite; touch /tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-stdout /tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-stderr; /tmp/autopkgtest.epy1pq/build.KhE/s rc/debian/tests/upstream-simulation-test-suite 2> >(tee -a /tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-stderr >&2) > >(tee -a /tmp/autopkgtest.epy1pq/upstream-simulation-test-suit e-stdout); 0 1000 3728 3720 20 0 2600 732 do_wai S ? 0:00 \_ /bin/sh /tmp/autopkgtest.epy1pq/build.KhE/src/debian/tests/upstream-simulation-test-suite 1 1000 3729 3728 20 0 8608 1896 do_wai S ? 0:00 \_ bash -c set -e; export USER=`id -nu`; . /etc/profile >/dev/null 2>&1 || true; . ~/.profile >/dev /null 2>&1 || true; buildtree="/tmp/autopkgtest.epy1pq/build.KhE/src"; mkdir -p -m 1777 -- "/tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-artifacts"; export AUTOPKGTEST_ARTIFACTS="/ tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-artifacts"; export ADT_ARTIFACTS="$AUTOPKGTEST_ARTIFACTS"; mkdir -p -m 755 "/tmp/autopkgtest.epy1pq/autopkgtest_tmp"; export AUTOPKGTEST _TMP="/tmp/autopkgtest.epy1pq/autopkgtest_tmp"; export ADTTMP="$AUTOPKGTEST_TMP"; export DEBIAN_FRONTEND=noninteractive; export LANG=C.UTF-8; export DEB_BUILD_OPTIONS=parallel=2; unset LANGU AGE LC_CTYPE LC_NUMERIC LC_TIME LC_COLLATE LC_MONETARY LC_MESSAGES LC_PAPER LC_NAME LC_ADDRESS LC_TELEPHONE LC_MEASUREMENT LC_IDENTIFICATION LC_ALL;rm -f /tmp/autopkgtest_script_pid; set -C; echo $$ > /tmp/autopkgtest_script_pid; set +C; trap "rm -f /tmp/autopkgtest_script_pid" EXIT INT QUIT PIPE; cd "$buildtree"; chmod +x /tmp/autopkgtest.epy1pq/build.KhE/src/debian/tests/ upstream-simulation-test-suite; touch /tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-stdout /tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-stderr; /tmp/autopkgtest.epy1pq/bui ld.KhE/src/debian/tests/upstream-simulation-test-suite 2> >(tee -a /tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-stderr >&2) > >(tee -a /tmp/autopkgtest.epy1pq/upstream-simulation-t est-suite-stdout); 0 1000 3730 3729 20 0 7228 848 pipe_w S ? 0:00 | \_ tee -a /tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-stderr 1 1000 3731 3728 20 0 8608 1756 do_wai S ? 0:00 \_ bash -c set -e; export USER=`id -nu`; . /etc/profile >/dev/null 2>&1 || true; . ~/.profile >/dev /null 2>&1 || true; buildtree="/tmp/autopkgtest.epy1pq/build.KhE/src"; mkdir -p -m 1777 -- "/tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-artifacts"; export AUTOPKGTEST_ARTIFACTS="/ tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-artifacts"; export ADT_ARTIFACTS="$AUTOPKGTEST_ARTIFACTS"; mkdir -p -m 755 "/tmp/autopkgtest.epy1pq/autopkgtest_tmp"; export AUTOPKGTEST _TMP="/tmp/autopkgtest.epy1pq/autopkgtest_tmp"; export ADTTMP="$AUTOPKGTEST_TMP"; export DEBIAN_FRONTEND=noninteractive; export LANG=C.UTF-8; export DEB_BUILD_OPTIONS=parallel=2; unset LANGU AGE LC_CTYPE LC_NUMERIC LC_TIME LC_COLLATE LC_MONETARY LC_MESSAGES LC_PAPER LC_NAME LC_ADDRESS LC_TELEPHONE LC_MEASUREMENT LC_IDENTIFICATION LC_ALL;rm -f /tmp/autopkgtest_script_pid; set -C; echo $$ > /tmp/autopkgtest_script_pid; set +C; trap "rm -f /tmp/autopkgtest_script_pid" EXIT INT QUIT PIPE; cd "$buildtree"; chmod +x /tmp/autopkgtest.epy1pq/build.KhE/src/debian/tests/ upstream-simulation-test-suite; touch /tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-stdout /tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-stderr; /tmp/autopkgtest.epy1pq/bui ld.KhE/src/debian/tests/upstream-simulation-test-suite 2> >(tee -a /tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-stderr >&2) > >(tee -a /tmp/autopkgtest.epy1pq/upstream-simulation-t est-suite-stdout); 0 1000 3732 3731 20 0 7228 780 pipe_w S ? 0:00 | \_ tee -a /tmp/autopkgtest.epy1pq/upstream-simulation-test-suite-stdout 0 1000 3794 3728 20 0 8608 3300 do_wai S ? 0:00 \_ /bin/bash ./run -i 20 -m 2 0 1000 3798 3794 20 0 9136 3992 do_wai S ? 0:00 \_ /bin/bash ./001-defaults 0 1000 3833 3798 20 0 5928 1864 skb_wa S ? 0:00 \_ /tmp/autopkgtest.epy1pq/autopkgtest_tmp/clknetsim -o tmp/log.offset -f tmp/log.freq -p tmp/log.packets -R 1 -r 210 -l 10000 -s tmp/sock tmp/conf 2
Seems to be a block on network on __skb_wait_ for_more_ packets
$cat /proc/3833/wchan for_more_ packets
__skb_wait_
From strace POV that is a wait in accept that does not unblock:
$ sudo strace -rT -p 3833
strace: Process 3833 attached
0.000000 accept(6, NULL, NULL
<hangs>
The logs are no help: t.epy1pq/ upstream- simulation- test-suite- stderr => empty t.epy1pq/ upstream- simulation- test-suite- stdout => matches the console
/tmp/autopkgtes
/tmp/autopkgtes
$ cat /tmp/autopkgtes t.epy1pq/ upstream- simulation- test-suite- stdout st.epy1pq/ autopkgtest_ tmp' st.epy1pq/ autopkgtest_ tmp'
make: Entering directory '/tmp/autopkgte
cc -O2 -Wall -g -fPIC -c -o client.o client.c
cc -O2 -Wall -g -fPIC -shared -o clknetsim.so client.o -ldl -lm
g++ -O2 -Wall -g -fPIC -c -o clock.o clock.cc
g++ -O2 -Wall -g -fPIC -c -o node.o node.cc
g++ -O2 -Wall -g -fPIC -c -o generator.o generator.cc
g++ -O2 -Wall -g -fPIC -c -o network.o network.cc
g++ -O2 -Wall -g -fPIC -c -o server.o server.cc
g++ -O2 -Wall -g -fPIC -c -o stats.o stats.cc
g++ -O2 -Wall -g -fPIC -o clknetsim clock.o node.o generator.o network.o server.o stats.o
make: Leaving directory '/tmp/autopkgte
001-defaults
<hang>
Noisy PS output:
4 0 506 1 20 0 2600 1920 - Ss ttyS1 0:00 /bin/sh "/tmp/autopkgte st.epy1pq/ build.KhE/ src"; mkdir -p -m 1777 -- "/tmp/autopkgte st.epy1pq/ upstream- simulation- test-suite- artifacts" ; export AUTOPKGTEST_ARTIFA autopkgtest. epy1pq/ upstream- simulation- test-suite- artifacts" ; export ADT_ARTIFACTS= "$AUTOPKGTEST_ ARTIFACTS" ; mkdir -p -m 755 "/tmp/autopkgte st.epy1pq/ autopkgtest_ tmp"; export AUTOP TMP="/tmp/ autopkgtest. epy1pq/ autopkgtest_ tmp"; export ADTTMP= "$AUTOPKGTEST_ TMP"; export DEBIAN_ FRONTEND= noninteractive; export LANG=C.UTF-8; export DEB_BUILD_ OPTIONS= parallel= 2; unset t_script_ pi t_script_ pid; set +C; trap "rm -f /tmp/autopkgtes t_script_ pid" EXIT INT QUIT PIPE; cd "$buildtree"; chmod +x /tmp/autopkgtes t.epy1pq/ build.KhE/ src/debian/ simulation- test-suite; touch /tmp/autopkgtes t.epy1pq/ upstream- simulation- test-suite- stdout /tmp/autopkgtes t.epy1pq/ upstream- simulation- test-suite- stderr; /tmp/autopkgtes t.epy1 KhE/src/ debian/ tests/upstream- simulation- test-suite 2> >(tee -a /tmp/autopkgtes t.epy1pq/ upstream- simulation- test-suite- stderr >&2) > >(tee -a /tmp/autopkgtes t.epy1pq/ upstream- simula suite-stdout) ; "/tmp/autopkgte st.epy1pq/ build.KhE/ src"; mkdir -p -m 1777 -- "/tmp/autopkgte st.epy1pq/ upstream- simulation- test-suite- artifacts" ; export AUTOPKGTEST_ ARTIFACTS= "/tmp/auto epy1pq/ upstream- simulation- test-suite- artifacts" ; export ADT_ARTIFACTS= "$AUTOPKGTEST_ ARTIFACTS" ; mkdir -p -m 755 "/tmp/autopkgte st.epy1pq/ autopkgtest_ tmp"; export AUTOPKGTEST_TMP="/t epy1pq/ autopkgtest_ tmp"; export ADTTMP= "$AUTOPKGTEST_ TMP"; export DEBIAN_ FRONTEND= noninteractive; export LANG=C.UTF-8; export DEB_BUILD_ OPTIONS= parallel= 2; unset LANGUAGE LC_C t_script_ pid; set -C; ech t_script_ pid; set +C; trap "rm -f /tmp/autopkgtes t_script_ pid" EXIT INT QUIT PIPE; cd "$buildtree"; chmod +x /tmp/autopkgtes t.epy1pq/ build.KhE/ src/debian/ tests/upstream test-suite; touch /tmp/autopkgtes t.epy1pq/ upstream- simulation- test-suite- stdout /tmp/autopkgtes t.epy1pq/ upstream- simulation- test-suite- stderr; /tmp/autopkgtes t.epy1pq/ build.KhE/ s tests/upstream- simulation- test-suite 2> >(tee -a /tmp/autopkgtes t.epy1pq/ upstream- simulation- test-suite- stderr >&2) > >(tee -a /tmp/autopkgtes t.epy1pq/ upstream- simulation- test-suit t.epy1pq/ build.KhE/ src/debian/ tests/upstream- simulation- test-suite "/tmp/autopkgte st.epy1pq/ build.KhE/ src"; mkdir -p -m 1777 -- "/tmp/autopkgte st.epy1pq/ upstream- simulation- test-suite- artifacts" ; export AUTOPKGTEST_ ARTIFACTS= "/ .epy1pq/ upstream- simulation- test-suite- artifacts" ; export ADT_ARTIFACTS= "$AUTOPKGTEST_ ARTIFACTS" ; mkdir -p -m 755 "/tmp/autopkgte st.epy1pq/ autopkgtest_ tmp"; export AUTOPKGTEST tmp/autopkgtest .epy1pq/ autopkgtest_ tmp"; export ADTTMP= "$AUTOPKGTEST_ TMP"; export DEBIAN_ FRONTEND= noninteractive; export LANG=C.UTF-8; export DEB_BUILD_ OPTIONS= parallel= 2; unset LANGU t_script_ pid; set t_script_ pid; set +C; trap "rm -f /tmp/autopkgtes t_script_ pid" EXIT INT QUIT PIPE; cd "$buildtree"; chmod +x /tmp/autopkgtes t.epy1pq/ build.KhE/ src/debian/ tests/ simulation- test-suite; touch /tmp/autopkgtes t.epy1pq/ upstream- simulation- test-suite- stdout /tmp/autopkgtes t.epy1pq/ upstream- simulation- test-suite- stderr; /tmp/autopkgtes t.epy1pq/ bui src/debian/ tests/upstream- simulation- test-suite 2> >(tee -a /tmp/autopkgtes t.epy1pq/ upstream- simulation- test-suite- stderr >&2) > >(tee -a /tmp/autopkgtes t.epy1pq/ upstream- simulation- t t.epy1pq/ upstream- simulation- test-suite- stderr "/tmp/autopkgte st.epy1pq/ build.KhE/ src"; mkdir -p -m 1777 -- "/tmp/autopkgte st.epy1pq/ upstream- simulation- test-suite- artifacts" ; export AUTOPKGTEST_ ARTIFACTS= "/ .epy1pq/ upstream- simulation- test-suite- artifacts" ; export ADT_ARTIFACTS= "$AUTOPKGTEST_ ARTIFACTS" ; mkdir -p -m 755 "/tmp/autopkgte st.epy1pq/ autopkgtest_ tmp"; export AUTOPKGTEST tmp/autopkgtest .epy1pq/ autopkgtest_ tmp"; export ADTTMP= "$AUTOPKGTEST_ TMP"; export DEBIAN_ FRONTEND= noninteractive; export LANG=C.UTF-8; export DEB_BUILD_ OPTIONS= parallel= 2; unset LANGU t_script_ pid; set t_script_ pid; set +C; trap "rm -f /tmp/autopkgtes t_script_ pid" EXIT INT QUIT PIPE; cd "$buildtree"; chmod +x /tmp/autopkgtes t.epy1pq/ build.KhE/ src/debian/ tests/ simulation- test-suite; touch /tmp/autopkgtes t.epy1pq/ upstream- simulation- test-suite- stdout /tmp/autopkgtes t.epy1pq/ upstream- simulation- test-suite- stderr; /tmp/autopkgtes t.epy1pq/ bui src/debian/ tests/upstream- simulation- test-suite 2> >(tee -a /tmp/autopkgtes t.epy1pq/ upstream- simulation- test-suite- stderr >&2) > >(tee -a /tmp/autopkgtes t.epy1pq/ upstream- simulation- t t.epy1pq/ upstream- simulation- test-suite- stdout t.epy1pq/ autopkgtest_ tmp/clknetsim -o tmp/log.offset -f tmp/log.freq -p tmp/log.packets -R 1 -r 210 -l 10000 -s tmp/sock tmp/conf 2
1 0 3690 506 20 0 2600 128 - S+ ttyS1 0:00 \_ /bin/sh
4 0 3691 3690 20 0 8172 3660 - S+ ttyS1 0:00 \_ su -s /bin/bash ubuntu -c set -e; export USER=`id -nu`; . /etc/profile >/dev/null 2>&1 || true; . ~/.profile
>/dev/null 2>&1 || true; buildtree=
CTS="/tmp/
KGTEST_
LANGUAGE LC_CTYPE LC_NUMERIC LC_TIME LC_COLLATE LC_MONETARY LC_MESSAGES LC_PAPER LC_NAME LC_ADDRESS LC_TELEPHONE LC_MEASUREMENT LC_IDENTIFICATION LC_ALL;rm -f /tmp/autopkgtes
d; set -C; echo $$ > /tmp/autopkgtes
tests/upstream-
pq/build.
tion-test-
4 1000 3720 3691 20 0 8608 3852 do_wai Ss ? 0:00 \_ bash -c set -e; export USER=`id -nu`; . /etc/profile >/dev/null 2>&1 || true; . ~/.profile >/dev/null 2>
&1 || true; buildtree=
pkgtest.
mp/autopkgtest.
TYPE LC_NUMERIC LC_TIME LC_COLLATE LC_MONETARY LC_MESSAGES LC_PAPER LC_NAME LC_ADDRESS LC_TELEPHONE LC_MEASUREMENT LC_IDENTIFICATION LC_ALL;rm -f /tmp/autopkgtes
o $$ > /tmp/autopkgtes
-simulation-
rc/debian/
e-stdout);
0 1000 3728 3720 20 0 2600 732 do_wai S ? 0:00 \_ /bin/sh /tmp/autopkgtes
1 1000 3729 3728 20 0 8608 1896 do_wai S ? 0:00 \_ bash -c set -e; export USER=`id -nu`; . /etc/profile >/dev/null 2>&1 || true; . ~/.profile >/dev
/null 2>&1 || true; buildtree=
tmp/autopkgtest
_TMP="/
AGE LC_CTYPE LC_NUMERIC LC_TIME LC_COLLATE LC_MONETARY LC_MESSAGES LC_PAPER LC_NAME LC_ADDRESS LC_TELEPHONE LC_MEASUREMENT LC_IDENTIFICATION LC_ALL;rm -f /tmp/autopkgtes
-C; echo $$ > /tmp/autopkgtes
upstream-
ld.KhE/
est-suite-stdout);
0 1000 3730 3729 20 0 7228 848 pipe_w S ? 0:00 | \_ tee -a /tmp/autopkgtes
1 1000 3731 3728 20 0 8608 1756 do_wai S ? 0:00 \_ bash -c set -e; export USER=`id -nu`; . /etc/profile >/dev/null 2>&1 || true; . ~/.profile >/dev
/null 2>&1 || true; buildtree=
tmp/autopkgtest
_TMP="/
AGE LC_CTYPE LC_NUMERIC LC_TIME LC_COLLATE LC_MONETARY LC_MESSAGES LC_PAPER LC_NAME LC_ADDRESS LC_TELEPHONE LC_MEASUREMENT LC_IDENTIFICATION LC_ALL;rm -f /tmp/autopkgtes
-C; echo $$ > /tmp/autopkgtes
upstream-
ld.KhE/
est-suite-stdout);
0 1000 3732 3731 20 0 7228 780 pipe_w S ? 0:00 | \_ tee -a /tmp/autopkgtes
0 1000 3794 3728 20 0 8608 3300 do_wai S ? 0:00 \_ /bin/bash ./run -i 20 -m 2
0 1000 3798 3794 20 0 9136 3992 do_wai S ? 0:00 \_ /bin/bash ./001-defaults
0 1000 3833 3798 20 0 5928 1864 skb_wa S ? 0:00 \_ /tmp/autopkgtes