[U-Boot] netconsole: USB Ethernet connection dropping with ping or tftpboot

["Jörg Krause" <jkrause@posteo.de>]

I followed the instructions from Marek in 'M28 U-Boot Single-Wire Debug
preview' to enable NetConsole:
http://www.denx-cs.de/?q=blogm28singlewiredebug

I'm using mxsldr to flash the u-boot.sb image to RAM. This is the dmesg
output from my host:

        [31048.492181] usb 3-13: new high-speed USB device number 24
        using xhci_hcd
        [31048.667617] cdc_ether 3-13:1.0 eth0: register 'cdc_ether' at
        usb-0000:00:14.0-13, CDC Ethernet Device, 00:19:b8:00:00:01
        [31048.669101] cdc_ether 3-13:1.0 enp0s20u13: renamed from eth0
        [31048.696758] cdc_ether 3-13:1.0 enp0s20u13: kevent 12 may have
        been dropped

I noticed the 'kevent 12 may have been dropped' message here.

Nevertheless, NetworkManager shows me a USB Ethernet connection and
using './netconsole 10.0.0.2' I am able to communicate with the device,
e.g. 'nand info' outputs correctly.

But if I use 'ping 10.0.0.1' or 'tftpboot u-boot.sb' the network
connection drops. Both commands work fine if I switch back from
netconsole to serial in-/output.

This is the output from dmesg:
        [31620.215354] usb 3-13: USB disconnect, device number 24
        [31620.215422] cdc_ether 3-13:1.0 enp0s20u13: unregister
        'cdc_ether' usb-0000:00:14.0-13, CDC Ethernet Device

Do I missed something?

Best regards
J?rg Krause