From mboxrd@z Thu Jan  1 00:00:00 1970
From: llj098@gmail.com (lijin liu)
Date: Mon, 20 Dec 2010 16:27:11 +0800
Subject: add_timer crashes the kernel,Why?
Message-ID: <AANLkTi=419O_8qyNP91XzL+OutqU2Uv20c3qhSg1Fz3w@mail.gmail.com>
To: kernelnewbies@lists.kernelnewbies.org
List-Id: kernelnewbies.lists.kernelnewbies.org

Hello everyone!

I want to use the timer in my kernel module. I read the book  _Linux
kernel development 3rd version_  and LDD 3rd version.

Both the two books tell me write the code like this:

struct timer_list my_timer;
init_timer(&my_timer);

my_timer.expires = jiffies + wait;
my_timer.data = 0;
my_timer.function=my_function;

//active the timer:
add_timer(&timer);


When I insmod the module, the kernel crashed, and when I change my
code to *mod_timer* rather than add_timer.

It just works!

But why the add_timer crash the kernel?