Hello, Since the move of 3 commits from part 2 to part 3 (see "[GIT] reduce patchset 2 (up to kselftests)" thread), the first IPv6 test, on the commit introducing the kselftests, causes a crash. It is easy to reproduce: $ git checkout $(git log -1 --format=%H --grep "mptcp: add basic kselftest for mptcp" origin/net-next..origin/export) $ make -C tools/testing/selftests TARGETS=net/mptcp run_tests ## or if you have the scripts from the "scripts" branch: $ ./Dockerfile.virtme.sh virtme.sh Here is what I got: ns1 MPTCP -> ns1 (dead:beef:1::1:10003) MPTCP [ 59.569727] general protection fault: 0000 [#1] SMP NOPTI [ 59.570060] CPU: 0 PID: 354 Comm: mptcp_connect Not tainted 5.4.0-rc7+ #321 [ 59.570060] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 59.570060] RIP: 0010:__ipv6_sock_mc_close+0x82/0x100 [ 59.570060] Code: 4c 89 fa e8 d0 e3 ff ff 4d 85 ff 75 44 3e 41 83 2c 24 40 48 8d 7b 30 be 30 00 00 00 e8 47 b8 75 ff 48 8b 5d 58 48 85 db 74 34 <48> 8b 43 18 4c 89 f7 48 89 45 58 8b 73 10 e8 5b 9f ec ff 48 85 c0 [ 59.570060] RSP: 0018:ffffa8948021be20 EFLAGS: 00010206 [ 59.570060] RAX: 0000000000000001 RBX: 2185dbe0e23218d4 RCX: 0000000000000001 [ 59.570060] RDX: ffffa0c39edcd280 RSI: ffffa0c39e6b0380 RDI: ffffffff9c8fde20 [ 59.570060] RBP: ffffa0c39df244f8 R08: 0000000000000000 R09: 0000000000000000 [ 59.570060] R10: ffffa0c39e6b0380 R11: ffffa0c39deb3f10 R12: ffffa0c39df24140 [ 59.570060] R13: ffffa0c39df24000 R14: ffffa0c39ddb8000 R15: ffffa0c39e676c00 [ 59.570060] FS: 00007f09acb80500(0000) GS:ffffa0c39f200000(0000) knlGS:0000000000000000 [ 59.570060] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 59.570060] CR2: 00007fb168761e60 CR3: 000000001deda000 CR4: 00000000003406f0 [ 59.570060] Call Trace: [ 59.570060] ipv6_sock_mc_close+0x37/0x40 [ 59.570060] inet6_release+0x16/0x30 [ 59.570060] __sock_release+0x38/0xb0 [ 59.570060] sock_close+0xc/0x10 [ 59.570060] __fput+0xb1/0x240 [ 59.570060] task_work_run+0x79/0xa0 [ 59.570060] exit_to_usermode_loop+0xa5/0xb0 [ 59.570060] do_syscall_64+0xf4/0x120 [ 59.570060] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 59.570060] RIP: 0033:0x7f09ac67f8d4 [ 59.570060] Code: eb 89 e8 cf 43 02 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 8d 05 31 00 2e 00 8b 00 85 c0 75 13 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 3c f3 c3 66 90 53 89 fb 48 83 ec 10 e8 f4 fd [ 59.570060] RSP: 002b:00007ffcf9398688 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 [ 59.570060] RAX: 0000000000000000 RBX: 00007ffcf93986b8 RCX: 00007f09ac67f8d4 [ 59.570060] RDX: 0000000000000000 RSI: 00007ffcf939a6c0 RDI: 0000000000000003 [ 59.570060] RBP: 0000000000000003 R08: 00007f09ac95a20c R09: 00007f09ac95a240 [ 59.570060] R10: fffffffffffff7e5 R11: 0000000000000246 R12: 00007ffcf939a6c0 [ 59.570060] R13: 0000000000000000 R14: 0000000000000000 R15: 000000000000008f [ 59.570060] Modules linked in: [ 60.149224] ---[ end trace 5333410f2d3e653b ]--- [ 60.162408] RIP: 0010:__ipv6_sock_mc_close+0x82/0x100 [ 60.176519] Code: 4c 89 fa e8 d0 e3 ff ff 4d 85 ff 75 44 3e 41 83 2c 24 40 48 8d 7b 30 be 30 00 00 00 e8 47 b8 75 ff 48 8b 5d 58 48 85 db 74 34 <48> 8b 43 18 4c 89 f7 48 89 45 58 8b 73 10 e8 5b 9f ec ff 48 85 c0 [ 60.227674] RSP: 0018:ffffa8948021be20 EFLAGS: 00010206 [ 60.242295] RAX: 0000000000000001 RBX: 2185dbe0e23218d4 RCX: 0000000000000001 [ 60.262192] RDX: ffffa0c39edcd280 RSI: ffffa0c39e6b0380 RDI: ffffffff9c8fde20 [ 60.281343] RBP: ffffa0c39df244f8 R08: 0000000000000000 R09: 0000000000000000 [ 60.300763] R10: ffffa0c39e6b0380 R11: ffffa0c39deb3f10 R12: ffffa0c39df24140 [ 60.320332] R13: ffffa0c39df24000 R14: ffffa0c39ddb8000 R15: ffffa0c39e676c00 [ 60.339678] FS: 00007f09acb80500(0000) GS:ffffa0c39f200000(0000) knlGS:0000000000000000 [ 60.361732] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 60.377509] CR2: 00007fb168761e60 CR3: 000000001deda000 CR4: 00000000003406f0 ./mptcp_connect.sh: line 360: 354 Segmentation fault ip netns exec ${connector_ns} ./mptcp_connect -t $timeout -p $port -s ${cl_proto} $connect_addr < "$cin" > "$cout" (duration 980ms) [ FAIL ] client exit code 139, server 0 \nnetns ns1-5dd5919f-pDmJLu socket stat for 10003: State Recv-Q Send-Q Local Address:Port Peer Address:Port TIME-WAIT 0 0 [dead:beef:1::1]:10003 [dead:beef:1::1]:36930 timer:(timewait,58sec,0) cwnd:2 reordering:0 \nnetns ns1-5dd5919f-pDmJLu socket stat for 10003: State Recv-Q Send-Q Local Address:Port Peer Address:Port FAIL: Could not even run loopback v6 test Is there someone who would like to have a look? :-) Thank you! Cheers, Matt -- Matthieu Baerts | R&D Engineer matthieu.baerts(a)tessares.net Tessares SA | Hybrid Access Solutions www.tessares.net 1 Avenue Jean Monnet, 1348 Louvain-la-Neuve, Belgium