Same as @prezes_kk since OS 3.9 update and the Load Average increase up to 6.0 in Luci status.
2017-12-14T15:34:06+01:00 emerg kernel[]: [30807.660633] unregister_netdevice: waiting for lo to become free. Usage count = 1
2017-12-14T15:34:16+01:00 emerg kernel[]: [30817.840659] unregister_netdevice: waiting for lo to become free. Usage count = 1
2017-12-14T15:34:26+01:00 emerg kernel[]: [30828.020635] unregister_netdevice: waiting for lo to become free. Usage count = 1
2017-12-14T15:34:37+01:00 emerg kernel[]: [30838.250634] unregister_netdevice: waiting for lo to become free. Usage count = 1
2017-12-14T15:34:47+01:00 emerg kernel[]: [30848.440637] unregister_netdevice: waiting for lo to become free. Usage count = 1
2017-12-14T15:34:57+01:00 emerg kernel[]: [30858.640633] unregister_netdevice: waiting for lo to become free. Usage count = 1
