Debug application and kernel on android device using gdb

README.md

@@ -36,6 +36,8 @@
 
 [Script](./script)
 
+[GDB on android](./android_gdb.md)
+
 ## 使用方法(单独编译模块)或者放到内核目录中编译
 
 - make CC=your_compiler_path KERNELDIR=your_kernel_dir

android_gdb.md

@@ -0,0 +1,90 @@
+# 在android上使用gdb调试
+
+## android源码中的gdb和gdbserver工具
+
+gdbserver(GNU gdbserver (GDB) 7.6)
+
+	prebuilts/misc/android-arm/gdbserver/gdbserver
+
+gdb(GNU gdb (GDB) 7.6)
+
+	prebuilts/gcc/linux-x86/arm/arm-eabi-4.8/bin/arm-eabi-gdb
+
+## 应用调试(使用ADB转发端口连接)
+
+### 在target上准备被调试程序
+
+在开发板上启动gdbserver监听已经运行的程序的pid(比如911)
+
+	gdbserver :1234 --attach 911
+
+或者是手动执行该被调试程序
+
+	gdbserver :1234 app_need_to_be_debug
+
+### 在host上设置连接方法
+
+启动gdb
+
+	./prebuilts/gcc/linux-x86/arm/arm-eabi-4.8/bin/arm-eabi-gdb -tui
+
+host TCP端口4321转发到remote TCP端口1234,也可以在未启动gdb前配置好
+
+	(gdb) shell adb forward tcp:4321 tcp:1234
+
+连接远程target
+
+	(gdb) target remote localhost:4321
+
+库文件绝对路径
+
+	set solib-absolute-prefix /android_src/out/target/product/rk3288/symbols
+
+库文件相对路径
+
+	set solib-search-path /android_src/out/target/product/rk3288/symbols/system/lib
+
+加载调试二进制文件(io)对应源码目录(external/io)
+
+	(gdb) file /android_src/out/target/product/rk3288/symbols/system/xbin/io
+
+## 通过串口调试内核
+
+### 配置内核
+
+配置如下选项
+
+	CONFIG_KGDB=y
+	CONFIG_CONSOLE_POLL=y
+	CONFIG_HAVE_ARCH_KGDB=y
+	CONFIG_KGDB_SERIAL_CONSOLE=y
+	CONFIG_KGDB_KDB=y
+	CONFIG_KDB_CONTINUE_CATASTROPHIC=0
+
+### TARGET上打开KGDB调试开关
+
+关闭watchdog
+
+	echo 0 > /proc/sys/kernel/watchdog
+
+设置kgdb over console(其中ttyFIQ0是调试串口)
+
+	echo 'ttyFIQ0,115200' > /sys/module/kgdboc/parameters/kgdboc
+
+开启kgdb
+
+	echo g > /proc/sysrq-trigger
+
+### HOST上调试
+
+在android上使用SDK里的gdb工具
+
+	prebuilts/gcc/linux-x86/arm/arm-eabi-4.8/bin/arm-eabi-gdb -tui
+
+通过串口连接到TARGET(由于使用的是调试串口,所以需要关掉调试串口)
+
+	(gdb) target remote /dev/ttyUSB0
+
+加载未压缩的内核
+
+	file vmlinux