Making kernel module

yannifan · 02-04-2007, 06:45 AM

Hello ppl,
Im new to kernel programming and have been trying to build my first kernel module 'hello world'

Im totally confused even after checking many posts.

My source file is hello.c :
#include <linux/init.h>
#include <linux/module.h>
MODULE_LICENSE("Dual BSD/GPL");

static int hello_init(void)
{
printk(KERN_ALERT "Hello World\n");
return 0;
}
static int hello_exit(void)
{
printk(KERN_ALERT "Goodbye!\n");
return 0;
}
module_init(hello_init);
module_init(hello_exit);

I installed a kernel tree from kernel.org(2.6.1
then i did "make config"
this is in /usr/src/linux-2.6.28.6

The Makefile addition is :

#Hello World module
obj-m += hello.ko
KDIR = /usr/src/linux-2.6.18.6/
SUBDIRS = $(PWD)
KVERSION = $(shell uname -r)
all:
make -C /lib/modules/$(KVERSION)/build M=$(PWD) modules
clean:
make -C /lib/modules/$(KVERSION)/build M=$(PWD) clean
modules:
$(MAKE) -C $(KDIR) M=$(SUBDIRS) $@

Im not sure if this is correct (/lib/modules/2/6/15-27-386/build exists)
The source file is in /usr/src/linux*

I have linuxheaders installed in /usr/src
ie. /usr/src/linux-headers-2.6.15-27
and linux-headers-2.6.15-27-386 exist

donno wat to do after tat!!!

Am i in the rite direction.... How do i continue???
Pls help Am using ubuntu dapper drake

Cheers

PS: sorry if its a duplicate post couldnt help.
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Franklin52 · 02-04-2007, 08:00 AM

The version of the header and source files must match your kernel.
Check your kernel version with:

Code:

uname -r

If they don't google for how to install them.

And try this Makefile:

Code:

obj-m	+= hello.o
all:
	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules

clean:
	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean

BTW the whitespace before the command make must be the tab character; eight spaces will
not suffice.

Regards