*The i/f is in `fib_2` netns*, and the stack trace indicates that *it's waiting in `netlink_wait_allrefs()`*. `*dmesg*` shows that an (at the point of hanging) *unlisted interface* is *waiting for refcnt to drop to zero*. * from `*ps aux*` > sirpa 4986 0.0 0.2 463432 20520 ? Dl 12:43 0:00 * from `*dmesg*` > [ 853.064007] unregister_netdevice: waiting for eth10.333 to become > free. Usage count = 3 > [ 863.312007] unregister_netdevice: waiting for eth10.333 to become > free. Usage count = 3 * from */proc/<dpsd pid>/stack* > [<0>] msleep+0x15/0x18 > [<0>] netdev_run_todo+0x144/0x24c > [<0>] rtnetlink_rcv_msg+0x209/0x23e > [<0>] netlink_rcv_skb+0x56/0xa9 > [<0>] netlink_unicast+0x10a/0x199 > [<0>] netlink_sendmsg+0x2cf/0x310 > [<0>] sock_sendmsg+0x14/0x1e > [<0>] __sys_sendto+0xba/0xe1 > [<0>] __x64_sys_sendto+0x1f/0x22 > [<0>] do_syscall_64+0x79/0x12e > [<0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 > [<0>] 0xffffffffffffffff *The interface seen in dmesg does not show up in the output of* `ifconfig`: > root@du1:/# ip netns exec fib_2 ifconfig > eth11.336 Link encap:Ethernet HWaddr 98:a4:04:4f:7f:4a > UP BROADCAST MULTICAST MTU:1500 Metric:1 > RX packets:0 errors:0 dropped:0 overruns:0 frame:0 > TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 > collisions:0 txqueuelen:1000 > RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) > > eth12.339 Link encap:Ethernet HWaddr 98:a4:04:4f:7f:4b > UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 > RX packets:0 errors:0 dropped:0 overruns:0 frame:0 > TX packets:282 errors:0 dropped:0 overruns:0 carrier:0 > collisions:0 txqueuelen:1000 > RX bytes:0 (0.0 B) TX bytes:18876 (18.4 KiB) > > lo Link encap:Local Loopback > inet addr:127.0.0.1 Mask:255.0.0.0 > inet6 addr: ::1/128 Scope:Host > UP LOOPBACK RUNNING MTU:16436 Metric:1 > RX packets:360 errors:0 dropped:0 overruns:0 frame:0 > TX packets:360 errors:0 dropped:0 overruns:0 carrier:0 > collisions:0 txqueuelen:1000 > RX bytes:37838 (36.9 KiB) TX bytes:37838 (36.9 KiB) PRELIMINARY INVESTIGATION: ==================================================================== The investigation done points to *currently unresolved netdev/namespace clean-up issue*. See: [https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1711407] --> unregister_netdevice: waiting for lo to become free [https://lkml.org/lkml/2018/8/15/387] --> unregister_netdevice: waiting for DEV to become free Specifically this comment: [https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1711407/comments/7]
Please see the attachments for additional logs: tn_dpsd_dmesg.txt tn_dpsd_ifconfig_a.txt tn_dpsd_netstat.txt tn_dpsd_syslog.txt tn_dpsd_top.txt
