Android Systemtap 无法加载模块

Question

我正在尝试在我的 GT-i9300 上加载一个简单的 Systemtap 模块

我得到了错误

Error inserting module '/sdcard/systemtap/modules/monitor_fopen.ko': Unknown symbol in module

我采取的步骤:

---

1。在设备上获取根

我通过安装这个 Rom 来做到这一点

2。构建自定义内核

# ====================================================
# Add toolchain

user@ubuntu1210:~/Programs$ git clone https://android.googlesource.com/platform/prebuilts/gcc/linux-x86/arm/arm-linux-androideabi-4.7

user@ubuntu1210:~$ sudo gedit .bashrc


    # Toolchain
    export PATH=${PATH}:~/Programs/arm-linux-androideabi-4.7/bin


# Reboot ubuntu 
# ====================================================


# ====================================================
# Download and extract to ~/android/kernel : 
# https://github.com/SlimRoms/kernel_samsung_smdk4412.git

user@ubuntu1210:~$ cd android/kernel/kernel_samsung_smdk4412/


# ====================================================


# ====================================================
# Set configuration for compiling


user@ubuntu1210:~/android/kernel/kernel_samsung_smdk4412$ make clean -j4 ARCH=arm SUBARCH=arm CROSS_COMPILE=arm-linux-androideabi-

user@ubuntu1210:~/android/kernel/kernel_samsung_smdk4412$ make ARCH=arm SUBARCH=arm CROSS_COMPILE=arm-linux-androideabi- slim_i9300_defconfig

user@ubuntu1210:~/android/kernel/kernel_samsung_smdk4412$ gedit .config

    # Enable config parameters:
    CONFIG_DEBUG_INFO, CONFIG_KPROBES, CONFIG_RELAY, CONFIG_DEBUG_FS, CONFIG_MODULES, CONFIG_MODULE_UNLOAD


# ====================================================
# Build Kernel

user@ubuntu1210:~/android/kernel/kernel_samsung_smdk4412$ make -j4 ARCH=arm SUBARCH=arm CROSS_COMPILE=arm-linux-androideabi-

3。 Flash 构建 zImage 到设备

# Download and extract bootimg_tools.zip from
# http://forum.xda-developers.com/showpost.php?p=44670032&postcount=12
# 
# Download correct ROM .zip file and extract boot.img to the same folder as bootimg_tools

user@ubuntu1210:~/bootimg_tools$ perl split_bootimg.pl boot.img

user@ubuntu1210:~/bootimg_tools$ perl unpack_ramdisk boot.img-ramdisk.gz ramdisk

user@ubuntu1210:~/bootimg_tools$ perl repack_ramdisk ramdisk boot.img-ramdisk.cpio.gz

user@ubuntu1210:~/bootimg_tools$ cp /home/user/kernel_samsung_smdk4412/arch/arm/boot/zImage boot.img-kernel

user@ubuntu1210:~/bootimg_tools$ ./mkbootimg --kernel boot.img-kernel --ramdisk boot.img-ramdisk.cpio.gz --cmdline 'console=null androidboot.hardware=qcom user_debug=31 zcache' --base 0x80200000 --pagesize 2048 -o boot.img

# Download and install heimdall
# https://bitbucket.org/benjamin_dobell/heimdall/downloads

user@ubuntu1210:~/bootimg_tools$ adb reboot bootloader

user@ubuntu1210:~/bootimg_tools$ sudo heimdall flash --BOOT boot.img --verbose

4。在PC上安装systemtap

user@ubuntu1210:~$ mkdir systemtap
user@ubuntu1210:~$ cd systemtap/
user@ubuntu1210:~/systemtap$ git clone https://github.com/flipreverse/systemtap-android.git
user@ubuntu1210:~/systemtap$ cd systemtap-android/
user@ubuntu1210:~/systemtap/systemtap-android$ git submodule init
user@ubuntu1210:~/systemtap/systemtap-android$ git submodule update
user@ubuntu1210:~/systemtap/systemtap-android$ sh build.sh 

5.创建 .stp 文件

user@ubuntu1210:~$ cd /home/user/systemtap/systemtap-android/scripts/
user@ubuntu1210:~$ vi monitor_fopen.stp

#! /usr/bin/stap


probe begin
{
        printf("start monitoring");
}

probe end
{
        printf("end monitoring");
}

6。使用已编译的内核从 .stp 文件构建 .ko 文件

user@ubuntu1210:~$ /home/user/systemtap/systemtap-android/installed/bin/stap 
-p 4 -v  
-a arm 
-B CROSS_COMPILE=/home/user/Programs/arm-linux-androideabi-4.7/bin/arm-linux-androideabi- 
-r /home/user/android/kernel/kernel_samsung_smdk4412/ 
-j /home/user/systemtap/systemtap-android/installed/share/systemtap/tapset/ 
-R /home/user/systemtap/systemtap-android/installed/share/systemtap/runtime/ 
-t -g -m monitor_fopen /home/user/systemtap/systemtap-android/scripts/monitor_fopen.stp

7.在运行自定义内核的设备上安装 Systemtap Android App

https://github.com/flipreverse/systemtap-android-app

8.启动应用程序并授予应用程序根访问权限

Superuser.apk 应该问你 Systemtap 是否可以有 root 权限

9.将步骤6中的.ko文件推送到sdcard

user@ubuntu1210:~$ adb push monitor_fopen.ko /sdcard/systemtap/modules/monitor_fopen.ko

10。加载模块

user@ubuntu1210:~$ adb shell
shell@android:/ $ su
root@android:/ # cd /data/data/com.systemtap.android
root@android:/data/data/com.systemtap.android # sh start_stap.sh   

modulename=monitor_fopen
moduledir=/sdcard/systemtap/modules
outputname=monitor_fopen_2014.mm.dd_sss
outputdir=/sdcard/systemtap/stap_output
logdir=/sdcard/systemtap/stap_log
rundir=/sdcard/systemtap/stap_run
stapdir=/data/data/com.systemtap.android
:q!

11。读取加载模块的结果

user@ubuntu1210:~$ adb shell
shell@android:/ $ cd sdcard/systemtap/stap_log/
shell@android:/sdcard/systemtap/stap_log $ cat monitor_fopen_2014.mm.dd_sss.txt

加载的内核模块:monitor_fopen.ko输出文件:monitor_fopen_2014.mm.dd_sss.*插入模块“/sdcard/systemtap/modules/monitor_fopen.ko”时出错:模块中的未知符号

---

我不知道我在哪一步出错了。有人知道吗？

Answer 1

感谢@adelphus，他记得我使用 dmesg，我发现了错误:

Android: Unknown symbol _GLOBAL_OFFSET_TABLE_

在this site的帮助下我将内核的 Makefile 编辑为

CFLAGS_MODULE   = -fno-pic

然后重做我的 OP 中的所有其他步骤。