5.3 Building Kernel/World

[Doug Hardie]

The instructions for building world/kernel for 4.x are straight forward 
and work fine.  However, I seem to have munged two 5.3 installations 
now.  I have been through all the UPDATING notes and the handbook and 
something is obviously not clear.

The approach I used is:

Clean install from 5.3 distribution.
make buildworld
create new config file LAFN
make buildkernel KERNCONF=LAFN
make installkernel KERNCONF=LAFN
reboot
make installworld
reboot

At that point It appeared I was using the LAFN kernel rather than 
generic.

However, tonight I tried to make a new kernel.  NO go:
ERROR: version of config(8) does not match kernel!
config version = 500012, version required = 500013

So I tried to reinstall the kernel:
make installkernel KERNCONF=LAFN
install -o root -g wheel -m 555   acpi.ko /boot/kernel
install: acpi.ko: No such file or directory

How are you supposed to build a new kernel that works?  How do I 
recover this?