I'm trying to build module.

But here's some issues.

ERROR: Kernel configuration is invalid. include/generated/autoconf.h or include/config/auto.conf are missing. Run 'make oldconfig && make prepare' on kernel src to fix it.

WARNING: Symbol version dump ./Module.symvers is missing; modules will have no dependencies and modversions.`

And here's my makefile

ifeq ($(KERNELRELEASE),)


KERNELDIR ?= /lib/modules/$(shell uname -r)/build
PWD := $(shell pwd)

modules:
    $(MAKE) -C $(KERNELDIR) M=$(PWD) modules

modules_install:
    $(MAKE) -C $(KERNELDIR) M=$(PWD) modules_install

clean:
    rm -rf *.o *~ core .depend .*.cmd *.ko *.mod.c .tmp_versions

.PHONY: modules modules_install clean

else
    # called from kernel build system: just declare what our modules are
    obj-m := hello.o hellop.o seq.o jit.o jiq.o sleepy.o complete.o \
             silly.o faulty.o kdatasize.o kdataalign.o
endif

I tried building like this:

export KERNELDIR=/path/to/extern/linux/source
make

How can I solve this problem?