http://www.pleaseguide.me/367/how-to-get-the-source-code-of-ubuntu
在按书作测试，有难点一一解决。
Ubuntu's Source code can be found here http://archive.ubuntu.com/
And to access kernel source code:
1. Make sure you have the source code repository enabled. To do this, go to System>Administration>Software Sources and check the source code repository. Reload the package information.
2. Open a terminal window and type
sudo apt-get install linux-source-2.x.xx
Replace 2.x.xx with the kernel version. If you don't know what your kernel version is, use the following command:
uname -r
The output will be something like this "2.6.27-9-generic"
In this case you will have to replace 2.x.xx with 2.6.27
And to access kernel source code:
1. Make sure you have the source code repository enabled. To do this, go to System>Administration>Software Sources and check the source code repository. Reload the package information.
2. Open a terminal window and type
sudo apt-get install linux-source-2.x.xx
Replace 2.x.xx with the kernel version. If you don't know what your kernel version is, use the following command:
uname -r
The output will be something like this "2.6.27-9-generic"
In this case you will have to replace 2.x.xx with 2.6.27