Compiling kernel

[Dan Jones <ddjones@riddlemaster.org>]

Attempting to compile kernel 2.4.20 under testing.  Getting the
following linker error:

ld -m elf_i386 -T /usr/src/kernel-source-2.4.20/arch/i386/vmlinux.lds
-e stext arch/i386/kernel/head.o arch/i386/kernel/init_task.o
init/main.o init/version.o init/do_mounts.o \
	--start-group \
	arch/i386/kernel/kernel.o arch/i386/mm/mm.o kernel/kernel.o mm/mm.o
fs/fs.o ipc/ipc.o \
	 drivers/char/char.o drivers/block/block.o drivers/misc/misc.o
drivers/net/net.o drivers/media/media.o drivers/ide/idedriver.o
drivers/cdrom/driver.o drivers/pci/driver.o drivers/pnp/pnp.o
drivers/video/video.o drivers/input/inputdrv.o \
	net/network.o \
	/usr/src/kernel-source-2.4.20/arch/i386/lib/lib.a
/usr/src/kernel-source-2.4.20/lib/lib.a
/usr/src/kernel-source-2.4.20/arch/i386/lib/lib.a \
	--end-group \
	-o vmlinux
net/network.o(.text+0xdc67): In function `rtnetlink_rcv':
: undefined reference to `rtnetlink_rcv_skb'
make: *** [vmlinux] Error 1

I assume that I need to enable an option that I have disabled but I'm
not sure which one.