> so it may be that the mi_ref is getting scribbled on somewhere else.
It's worth investigating, but might not be related to this particular issue. Detaching a driver instance is not the only way to change MTU. bge_m_setprop(DLD_PROP_DEFMTU) only returns EBUSY when bgep->bge_mac_state == BGE_MAC_STARTED. If you stop the mac then call mi_setprop, it should reinitialize with the the value. I think we should work this angle first. -Artem
