Linux(fedora 10)Hello World模块

一个内核模块的例子：

#include <linux/init.h>
#include <linux/module.h>
MODULE_LICENSE("GPL");
static int hello_init(void)
{
    printk(KERN_ALERT"hello,world!/n");
    return 0;
}
static void hello_exit(void)
{
    printk(KERN_ALERT"Goodbye,cruel world!/n");
}
module_init(hello_init);
module_exit(hello_exit);

Makefile文件

ifneq ($(KERNELRELEASE),)
obj-m := hello.o
else
KERNELDIR ?= /usr/src/kernels/$(shell uname -r)
PWD := $(shell pwd)
INSTALLDIR = /opt/rootfs/lib/modules
modules:
  $(MAKE) -C $(KERNELDIR) M=$(PWD) modules
modules_install:
  cp hello.ko $(INSTALLDIR)
clean:
  rm -rf *.o *~core .depend .*.cmd *.ko *.mod.c .tmp_versions
.PHONY:modules modules_install clean
endif

在shell下

[root@localhost hello_driver]# 
  make
 
 
 

  make -C /usr/src/kernels/2.6.27.5-117.fc10.i686 M=/opt/hello_driver modules
 
 
 

  make[1]: Entering directory `/usr/src/kernels/2.6.27.5-117.fc10.i686'
 
 
 

    CC [M]  /opt/hello_driver/hello.o
 
 
 

    Building modules, stage 2.
 
 
 

    MODPOST 1 modules
 
 
 

    CC      /opt/hello_driver/hello.mod.o
 
 
 

    LD [M]  /opt/hello_driver/hello.ko
 
 
 

  make[1]: Leaving directory `/usr/src/kernels/2.6.27.5-117.fc10.i686'
 
 
 

  [root@localhost hello_driver]#
   ls
 
 
 

  hello.c   hello.mod.c  hello.o   Makefile~       modules.order
 
 
 

  hello.ko  hello.mod.o  Makefile  Module.markers  Module.symvers
 
 
 

  [root@localhost hello_driver]#
   insmod hello.ko
 
 
 

  [root@localhost hello_driver]# 
  lsmod | grep hello
 
 
 

  hello                   5248  0 
 
 
 

  [root@localhost hello_driver]# 
  rmmod hello
 
 
 

  [root@localhost hello_driver]# 
  tail -n 2 /var/log/messages
 
 
 

  Jun 23 19:33:39 localhost kernel: hello,world!
 
 
 

  Jun 23 19:33:55 localhost kernel: Goodbye,cruel world!
 
 
 

  [root@localhost hello_driver]#
   dmesg | tail