Re: BUG: tools/testing/selftests/net/l2_tos_ttl_inherit.sh hangs when selftest restarted

From: Guillaume Nault
Date: Sun Jan 08 2023 - 09:05:51 EST


On Sun, Jan 08, 2023 at 10:11:25AM +0100, Mirsad Goran Todorovac wrote:
> [root@pc-mtodorov marvin]# tcpdump --immediate-mode -p -v -i veth0 -n
> dropped privs to tcpdump
> tcpdump: listening on veth0, link-type EN10MB (Ethernet), capture size 262144 bytes
> 08:30:22.835825 IP (tos 0x0, ttl 64, id 2490, offset 0, flags [none], proto UDP (17), length 78)
> 198.18.0.1.35195 > 198.18.0.2.vxlan: VXLAN, flags [I] (0x08), vni 100
> ARP, Ethernet (len 6), IPv4 (len 4), Request who-has 198.19.0.2 tell 198.19.0.1, length 28
> 08:30:22.835926 IP (tos 0x0, ttl 64, id 1388, offset 0, flags [none], proto UDP (17), length 78)
> 198.18.0.2.35195 > 198.18.0.1.vxlan: VXLAN, flags [I] (0x08), vni 100
> ARP, Ethernet (len 6), IPv4 (len 4), Reply 198.19.0.2 is-at a6:45:d5:c4:93:1f, length 28
> 08:30:22.835976 IP (tos 0xc0, ttl 64, id 29533, offset 0, flags [none], proto ICMP (1), length 106)
> 198.18.0.1 > 198.18.0.2: ICMP host 198.18.0.1 unreachable - admin prohibited filter, length 86
> IP (tos 0x0, ttl 64, id 1388, offset 0, flags [none], proto UDP (17), length 78)
> 198.18.0.2.35195 > 198.18.0.1.vxlan: VXLAN, flags [I] (0x08), vni 100
> ARP, Ethernet (len 6), IPv4 (len 4), Reply 198.19.0.2 is-at a6:45:d5:c4:93:1f, length 28

For some reasons, your host doesn't accept the VXLAN packets received
over veth0. I guess there are some firewalling rules incompatible with
this tests script.

> > -------- >8 --------
> >
> > Isolate testing environment and ensure everything is cleaned up on
> > exit.
> >
> > diff --git a/tools/testing/selftests/net/l2_tos_ttl_inherit.sh b/tools/testing/selftests/net/l2_tos_ttl_inherit.sh

> Wow, Guillaueme, this patch actually made things unstuck :)

Great! The patch isolates the testing environment, making it less
dependent from the host that runs it. So the routing and firewalling
configurations don't interfere anymore.

> The entire tools/tests/selftests/net section now had a PASS w "OK", save for a couple of tests here:
>
> not ok 1 selftests: nci: nci_dev # exit=1
> not ok 12 selftests: net: nat6to4.o
> not ok 13 selftests: net: run_netsocktests # exit=1
> not ok 29 selftests: net: udpgro_bench.sh # exit=255
> not ok 30 selftests: net: udpgro.sh # exit=255
> not ok 37 selftests: net: fcnal-test.sh # TIMEOUT 1500 seconds
> not ok 38 selftests: net: l2tp.sh # exit=2
> not ok 46 selftests: net: icmp_redirect.sh # exit=1
> not ok 55 selftests: net: vrf_route_leaking.sh # exit=1
> not ok 59 selftests: net: udpgro_fwd.sh # exit=1
> not ok 60 selftests: net: udpgro_frglist.sh # exit=255
> not ok 61 selftests: net: veth.sh # exit=1
> not ok 68 selftests: net: srv6_end_dt46_l3vpn_test.sh # exit=1
> not ok 69 selftests: net: srv6_end_dt4_l3vpn_test.sh # exit=1
> not ok 75 selftests: net: arp_ndisc_evict_nocarrier.sh # exit=255
> not ok 83 selftests: net: test_ingress_egress_chaining.sh # exit=1
> not ok 1 selftests: net/hsr: hsr_ping.sh # TIMEOUT 45 seconds
> not ok 3 selftests: net/mptcp: mptcp_join.sh # exit=1
>
> If you are interested in additional diagnostics, this is a very interesting part of the
> Linux kernel testing ...
>
> There was apparent hang in selftest/net/fcnal-test.sh as well.
> I can help you with the diagnostics if you wish? Thanks.
>
> If I could make them all work both on Ubuntu 22.10 kinetic kudu and AlmaLinux 8.7
> stone smilodon (CentOS fork), this would be a milestone for me :)

I'm surprised you have so many failures. Feel free to report them
individually. Don't forget to Cc the authors of the scripts. Just
pay attention not to overwhelm people.

I can probably help with the l2tp.sh failure and maybe with the
fcnal-test.sh hang. Please report them in their own mail thread.

> Have a nice day!
>
> Regards,
> Mirsad
>
> --
> Mirsad Goran Todorovac
> Sistem inženjer
> Grafički fakultet | Akademija likovnih umjetnosti
> Sveučilište u Zagrebu
>
> System engineer
> Faculty of Graphic Arts | Academy of Fine Arts
> University of Zagreb, Republic of Croatia
> The European Union
>
>