Error “SIOCSIFFLAGS: Invalid argument” when executing ifconfig

I noticed this error when executing ifconfig just after turning VStarCam H6837WI on:

# ifconfig eth0 up                                           
ifconfig: SIOCSIFFLAGS: Invalid argument                                        

I didn’t investigate what is the root cause of this error, but I noticed if I execute /mnt/system/bin/encoder and reboot the board next it it will work.

Then I suspect there is some ethernet Micrel KSZ8851 PHY initialization done by encoder application.