I would suggest rewording the message a bit to something like:

Defer if_up() until after the interface's if_ioctl method is called.

This ensures the interface is initialized by the interface driver before
it can be used by the rest of the system.

In D8905#185507, @jhb wrote:

I would suggest rewording the message a bit to something like:

Defer if_up() until after the interface's if_ioctl method is called.

This ensures the interface is initialized by the interface driver before
it can be used by the rest of the system.

Done. Thank you.

Seems fine to me; will let someone else approve.