I want to study linux kernel,but i am a freshman.Who can provide some
methods and experience for me?
Thanks for your help!

Start here: http://kernelnewbies.org/

Linux Kernel in a Nutshell You can download a pdf free, or buy the book from O'Reilly.

if you have c programming experience,
first prepare a debugging environment with KGDB,
then boot with kernel, using gdb.

Someone in the forum told me about the free kernel book too at http://www.kroah.com/lkn and I downloaded it and have been trying to understand it. I have been able to build the kernel 2.4.36 with it. Without some free books like that and the forum I think that I would have forgotten about Linux and had my mom and dad M$crosoft ME to Vista.

I want to learn more about it too.
"boot with kernel, using gdb"

I have no idea how to boot the Linux kernel with gdb. Can someone explain to me how to do that in a clear way so that I do not mess it up like I did when I tried to compile the kernel?

R.Love - Linux Kernel Development 2nd ed. may help

"newtovanilla," good sir or madam, relax!

I mean that sincerely and with not-a-trace of disrespect to you.

The reality of this situation is that you are diving into something totally-new to your present experience, and therefore, "details are going to be hitting you in the face" just as surely as if your family car had just encountered a cloud of Junebugs while you were driving down the Interstate at 75MPH.

What you need to try to master is ... sorting it all out. In the short run, you're going to be inundated with apparently disconnected details all competing for attention. You'll go stir-crazy if you try to satisfy them.

I suggest that you get a loose-leaf notebook and a number-two pencil. (Seriously. It works for me.) When a thing you don't understand comes whizzing by ... write it down, (yes, in pencil) and once you've written it down you can "let it go."

For instance: this bit about "gdb." Okay, no answer yet, maybe no answer for several weeks: let it go. Don't go chasing after that rabbit. Instead, continue to gather information. Write down in that notebook as a task-specific journal. Capture the questions and leave space for answers. Periodically re-read the whole thing.

It works.

Join the Kernel.org mailing list.

http://kernel.org/pub/linux/docs/lkml/

http://www.makelinux.net/kernel_map

and continue here:
http://kernelnewbies.org/KernelHacking

Sorry for the late answer.

What I mean is once you set up a kernel debugging
environment(source level debugging environment),
you can set breakpoint, evaluate any variable,
step into and over in runtime just like any application.
So running kernel boot process line by line is possible.
(It may took days and nights booting line by line)

There are several options for that debugging environment.

Try this first.

http://kgdb.linsyssoft.com/quickstart.htm

It is also easier, debugging with UML.
User Mode Linux is a user space build of kernel.
just like any compiled linux application. So you can debug it with gdb.

The other option is kgdb + qemu sytle.
Google "howto kgdb with qemu" for that.

But you need to remember this operation needs c programming
experience. If not, it would be painful and discouraging.

Good luck.