Removing the parser for bootpath gets rid of the broken additional interface. I expect that checking the return value of grub_ieee1275_get_property() when querying the mac also fixes it, and will investigate that shortly (as it seems the bootpath contains IP addresses, but not MAC addresses).
This is the culprit:
https:/ /git.savannah. gnu.org/ cgit/grub. git/commit/ grub-core/ net?id= 9585647a25b65f9 8db6bd22c569b34 795512f046
Removing the parser for bootpath gets rid of the broken additional interface. I expect that checking the return value of grub_ieee1275_ get_property( ) when querying the mac also fixes it, and will investigate that shortly (as it seems the bootpath contains IP addresses, but not MAC addresses).