[Android Q&A, Help & Troubleshooting] meglome:
Don't really know that much about this but I can see the stuff in the logs. Thanks for your help.

Here's what happens when I have the wifi connected and plug in the Lan.

[ 6087.391000] duplex
[ 6087.391000] 100m
[ 6087.392000] ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
[ 6087.395000] changed the Multicast,mcount=2
[ 6087.399000] add mac address:33:33:00:00:00:01,bit=1
[ 6087.404000] add mac address:01:00:5e:00:00:01,bit=32
[ 6087.408000] set hash low=2,high=1
[ 6087.412000] changed the filter setting to :4
[ 6087.418000] changed the Multicast,mcount=3
[ 6087.420000] add mac address:33:33:ff:cd:ee:af,bit=60
[ 6087.425000] add mac address:33:33:00:00:00:01,bit=1
[ 6087.430000] add mac address:01:00:5e:00:00:01,bit=32
[ 6087.435000] set hash low=2,high=10000001
[ 6087.439000] changed the filter setting to :4
[ 6087.518000] changed the Multicast,mcount=3
[ 6087.518000] add mac address:33:33:ff:cd:ee:af,bit=60
[ 6087.521000] add mac address:33:33:00:00:00:01,bit=1
[ 6087.526000] add mac address:01:00:5e:00:00:01,bit=32
[ 6087.531000] set hash low=2,high=10000001
[ 6087.535000] changed the filter setting to :4
[ 6087.561000] cpufreq-meson: transition: 300000 --> 400000
[ 6087.812000] changed the Multicast,mcount=3
[ 6087.812000] add mac address:33:33:ff:cd:ee:af,bit=60
[ 6087.816000] add mac address:33:33:00:00:00:01,bit=1
[ 6087.821000] add mac address:01:00:5e:00:00:01,bit=32
[ 6087.826000] set hash low=2,high=10000001
[ 6087.830000] changed the filter setting to :4
[ 6087.834000] netdev_close
[ 6087.836000] NET MDA is stoped,val=8502!
[ 6087.841000] eth0: closed

And here's what happens when I turn off the wifi.

[ 6212.214000] init: service 'dhcpcd_wlan0' is being killed
[ 6212.221000] init: waitpid returned pid 12221, status = 00000009
[ 6212.222000] init: process 'dhcpcd_wlan0', pid 12221 exited
[ 6212.228000] -871x_drv - drv_close, bup=1
[ 6212.243000] rtl8192c_set_FwJoinBssReport_cmd mstatus(0)
[ 6212.322000] init: service 'wpa_supplicant' is being killed
[ 6212.325000] init: waitpid returned pid 12199, status = 00000009
[ 6212.328000] init: process 'wpa_supplicant', pid 12199 exited
[ 6212.584000] netdev_open
[ 6212.584000] NET MDA descpter start addr=e227e800
[ 6212.586000] write mac add to:e3ca1848: 00 01 23 cd ee af |..#...|
[ 6212.592000] Current DMA mode=0
[ 6212.595000] eth0: opened (irq 8).
[ 6212.598000] changed the Multicast,mcount=1
[ 6212.599000] add mac address:01:00:5e:00:00:01,bit=32
[ 6212.604000] set hash low=0,high=1
[ 6212.607000] changed the filter setting to :4
[ 6212.612000] ADDRCONF(NETDEV_UP): eth0: link is not ready
[ 6212.634000] changed the Multicast,mcount=1
[ 6212.634000] add mac address:01:00:5e:00:00:01,bit=32
[ 6212.638000] set hash low=0,high=1
[ 6212.641000] changed the filter setting to :4
[ 6212.682000] +rtw_drv_halt
[ 6212.682000] ##########rtw_suspend_lock_uninit###########
[ 6212.684000] usbcore: deregistering interface driver rtl8192cu
[ 6212.690000] ###=> usb_read_port_complete => urb status(-108)
[ 6212.722000] +rtw_dev_remove
[ 6212.722000] rtw_sta_flush
[ 6212.944000] changed the Multicast,mcount=1
[ 6212.944000] add mac address:01:00:5e:00:00:01,bit=32
[ 6212.947000] set hash low=0,high=1
[ 6212.950000] changed the filter setting to :4
[ 6212.981000] ===> rtw_dev_unload
[ 6212.981000] usb_read_port_cancel
[ 6212.982000] usb_write_port_cancel
[ 6212.986000] ###> rtw_cmd_thread break.................
[ 6212.991000] ==> rtl8192cu_hal_deinit
[ 6212.994000] bkeepfwalive(0)
[ 6212.997000] card disble HWSM...........
[ 6213.006000] changed the Multicast,mcount=1
[ 6213.006000] add mac address:01:00:5e:00:00:01,bit=32
[ 6213.010000] set hash low=0,high=1
[ 6213.013000] changed the filter setting to :4
[ 6213.040000] <=== rtw_dev_unload
[ 6213.040000] +r871xu_dev_remove, hw_init_completed=0
[ 6213.044000] free_recv_skb_queue not empty, 4
[ 6213.047000] rtw_unregister_early_suspend
[ 6213.070000] =====> rtl8192c_free_hal_data =====
[ 6213.070000] <===== rtl8192c_free_hal_data =====
[ 6213.074000] usb attached..., try to reset usb device
[ 6213.261000] usb 2-1: reset high speed USB device using dwc_otg and address 3
[ 6213.472000] -r871xu_dev_remove, done
[ 6213.473000] -rtw_drv_halt
[ 6213.761000] cpufreq-meson: transition: 1000000 --> 900000
[ 6213.961000] cpufreq-meson: transition: 900000 --> 800000
[ 6213.981000] wifi 0
[ 6214.161000] usb 2-1: USB disconnect, address 3
[ 6214.361000] cpufreq-meson: transition: 800000 --> 700000
[ 6214.611000] duplex
[ 6214.611000] 100m
[ 6214.611000] ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
[ 6214.615000] changed the Multicast,mcount=2
[ 6214.619000] add mac address:33:33:00:00:00:01,bit=1
[ 6214.624000] add mac address:01:00:5e:00:00:01,bit=32
[ 6214.628000] set hash low=2,high=1
[ 6214.632000] changed the filter setting to :4
[ 6214.636000] changed the Multicast,mcount=3
[ 6214.640000] add mac address:33:33:ff:cd:ee:af,bit=60
[ 6214.645000] add mac address:33:33:00:00:00:01,bit=1
[ 6214.650000] add mac address:01:00:5e:00:00:01,bit=32
[ 6214.655000] set hash low=2,high=10000001
[ 6214.659000] changed the filter setting to :4
[ 6214.700000] changed the Multicast,mcount=3
[ 6214.700000] add mac address:33:33:ff:cd:ee:af,bit=60
[ 6214.703000] add mac address:33:33:00:00:00:01,bit=1
[ 6214.708000] add mac address:01:00:5e:00:00:01,bit=32
[ 6214.713000] set hash low=2,high=10000001
[ 6214.717000] changed the filter setting to :4