Linux内核编译，模块尺寸变大的解决办法

现象：    

    最近在研究Linux的裁剪定制，编译内核的时候发现编译后同样的模块比以前内核版本的大好多，比如下面这个例子：

[root@CentOS5 ~]# find /lib/modules/ -name ext3.ko

/lib/modules/3.8.8-chensh3.0/kernel/fs/ext3/ext3.ko

/lib/modules/2.6.18-308.el5/kernel/fs/ext3/ext3.ko

[root@CentOS5 ~]# ll -h /lib/modules/3.8.8-chensh3.0/kernel/fs/ext3/ext3.ko

-rw-r--r-- 1 root root 3.7M 09-08 07:33 /lib/modules/3.8.8-chensh3.0/kernel/fs/ext3/ext3.ko

[root@CentOS5 ~]# ll -h /lib/modules/2.6.18-308.el5/kernel/fs/ext3/ext3.ko

-rwxr--r-- 1 root root 226K 2012-02-22 /lib/modules/2.6.18-308.el5/kernel/fs/ext3/ext3.ko

[root@CentOS5 ~]# 

问题分析和解决办法：

    The default kernel configuration is configured to support as many hardware as possible. A non-stripped kernel with default configuration resulted in a size of 1897996 kB (including kernel + modules). When stripping many unnecessary drivers and options, it resulted in a size of 892892 kB which is a size reduction of 53% compared to the stock kernel.

    When installing the kernel modules, append the INSTALL_MOD_STRIP=1 option. This will strip all debugging symbols and reduced the size by 92% for me (from 892892 kB to 69356 kB). Note this will only affects modules to be installed and not the kernel (vmlinuz) itself.

Use the INSTALL_MOD_STRIP option for removing debugging symbols:

# make INSTALL_MOD_STRIP=1 modules_install

Similarly, for building the deb packages:

# make INSTALL_MOD_STRIP=1 deb-pkg