kernel threads

[sopel39]

Hi

I have some newbie questions about kernel threads in kernel 2.6 created with "kernel_thread" function.

1. Let's say user program "hello_world" called some system function "do_it". Then kernel function "sys_do_it" creates thread using "kernel_thread". Is the new thread child of the process "hello_world"?

2. Does kernel threads have same semantics as pthreads?

3. I read that kernel threads have initially blocked signals. I know that i have to unblock signals in kernel thread, but how do i receive them?

4. In my example if kernel thread is child of "hello_world" then what happens when i unblock signal SIGTERM (in what context signal handler function will be executed and who will receive it (process "hello_world" or my kernel thread))? Can kernel thread steal signal before process "hello_world" handle it?

5. How do i wait for kernel thread to finish? Can kernel thread's be zombies?

6. How do i gracefully finish execution of kernel thread (what do i have to call in kernel thread function)?

Thank very much
Sopel39

[kerim46]

I have searched over the net but could not find a good explanation of how to terminate a kernel thread.

For an academic project, I have created several kernel thread during system boot, and then try to kill them.

I use do_exit() in thread function to let thread to terminate itself bu I got this error
"unable to handle kernel paging request at virtual address 6f635f6f
printing eip:
.........
"

I used kill_proc(...) but got the same kind of error.

what is the true way to terminate a kernel thread?