4af4c0b93c
On some boards there is no eeprom to hold the nvram, in this case instead a board specific nvram is loaded from /lib/firmware. On most boards the macaddr=... setting in the /lib/firmware nvram file is ignored because the wifi/bt chip has a unique MAC programmed into the chip itself. But in some cases the actual MAC from the /lib/firmware nvram file gets used, leading to MAC conflicts. The MAC addresses in the troublesome nvram files seem to all come from the same nvram file template, so we can detect this by checking for the template nvram file MAC. Detect that the default MAC address is being used and replace it with a random MAC address to avoid MAC address conflicts. Note that udev will detect this is a random MAC based on /sys/class/net/wlan0/addr_assign_type and then replace this with a MAC based on hashing the netdev-name + the machine-id. So that the MAC address is both guaranteed to be unique per machine while it is still the same/persistent at each boot (assuming the default Link.MACAddressPolicy=persistent udev setting). Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Arend van Spriel <arend.vanspriel@broadcom.com> Signed-off-by: Kalle Valo <kvalo@kernel.org> Link: https://lore.kernel.org/r/20220708133712.102179-2-hdegoede@redhat.com