Linux how to debug OS freeze issue

Question

I am working on a kernel module and a user-space application to test that module.

The problem is that during testing my system hangs/freeze.

I have placed lots of debug prints in the code.

The last message that is printed is just before linux select call in my user-space application. Does select somehow freeze the system?

So, How can i debug that where is problem? whether the problem is on user-space application or kernel module?

Answer 1

As n.m mentioned, your userspace program can't freeze Linux, so its an error in your kernel module. The best way to debug this is to use a kernel debugger, and figure out what your module is doing wrong.

Common errors are uninitialized pointers that your module passes to the kernel or locking issues, so take a close look at those.

Answer 2

A userspace program cannot, by definition, freeze Linux. There's a bug in the kernel.