A hello program for the Android Kernel module compilation method and test results in the simulator

Hello module Source:

#include <linux/init.h>

#include <linux/module.h>

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);

Compile Hello.ko module Makefile code:

Obj-m: = hello.o

All

Make Arch=arm extra_cflags= "-d_config_arm_-fno-pic"-C $ (Kdir) m=$ (PWD) modules

Clean

$ (make)-C $ (Kdir) m=$ (PWD) Cleanhe

Make Hello.ko function:

Make cross_compile=arm-linux-androideabi-kdir=/opt/hackandroid/goldfish_0228

Note:kdir is kernel path. What ' s kernel path??? Please refer to:http://blog.csdn.net/yygydjkthh/article/details/20172023

Tested on Android emulator:

Run Android Emulator:

EMULATOR-AVD Android4.2.2-kernel Arch/arm/boot/zimage

Push Hello.ko to Emulator:

testhello$ ADB push hello.ko/data/local

kb/s (2648 bytes in 0.042s)

Note:what is Zimage?  How get the Zimage??? Please refer to:http://blog.csdn.net/yygydjkthh/article/details/20172023

testhello$ adb shell

root@android:/# CD data/local/

Root@android:/data/local # ls

Hello.ko

Root@android:/data/local # Insmod Hello.ko

Root@android:/data/local # Dmesg-c

<1>hello,world

Root@android:/data/local # Lsmod

Hello 702 0-live 0x00000000 (PO)

Root@android:/data/local # Rmmod Hello

Root@android:/data/local # Dmesg-c

<1>goodbye, Cruel World

Root@android:/data/local # Lsmod

Root@android:/data/local #

<1>hello,world

So, that ' s OK, good night: _).

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