Ubuntu
linux package

  1. Bug #1711407
  2. Comment #47

Comment 47 for bug 1711407

Revision history for this message
Jiri Horky (jiri-horky) wrote :

Hi Dan,

first of all thanks for looking into this long lasting, irritating issue.

I have tried your kernel (4.13.0-30-generic #33+hf1711407v20180118b2-Ubuntu SMP) on Ubuntu 17.10 and was able to get "unregister_netdevice: waiting for lo to become free. Usage count = 1" in less than 5 minutes :-(
Our environment spawns about 1 container a second that does either openvpn (both udp and tcp) or ipsec tunnel testing.
I don't see any debug output in the kernel log, the lines are just old ordinary:

[ 910.690908] unregister_netdevice: waiting for lo to become free. Usage count = 1
[ 920.806382] unregister_netdevice: waiting for lo to become free. Usage count = 1
[ 930.945869] unregister_netdevice: waiting for lo to become free. Usage count = 1
[ 941.025341] unregister_netdevice: waiting for lo to become free. Usage count = 1
[ 951.104797] unregister_netdevice: waiting for lo to become free. Usage count = 1
[ 961.184286] unregister_netdevice: waiting for lo to become free. Usage count = 1
[ 971.263749] unregister_netdevice: waiting for lo to become free. Usage count = 1

I don't even see any "net_free:" or "net_alloc:" messages in the log (and I checked the referrenced git and your recent patch and it does not seem to be there either).

PLease let me know how to enable the debug messages, so we can finally trace it down.

Thanks
Jiri Horky