module_register: cannot register pci/igb from if_igb.ko

[Alexey Prokopchuk]

Hi all.

My English is not very good, excuse me if I said something wrong

I have igb and em ethernet cards and kernel compiled with if_igb and 
if_em as modules. When both modules if_igb and if_em present in loader 
conf I see following message:

module_register: cannot register pci/em from if_igb.ko; already loaded 
from if_em.ko
Module pci/em failed to register: 17
module_register: cannot register pci/igb from if_igb.ko; already loaded 
from if_em.ko
Module pci/igb failed to register: 17

I tried to leave only if_em in loader.conf and noticed that igb device 
working, but module if_igb.ko does not loaded in kernel. So, I have only 
if_em.ko loaded and both em and igb cards working.
I'm confused and now I don't understand which driver should work with 
which device...