Re: kernel_thread ()

Theodore Y. Ts'o (tytso@MIT.EDU)
Fri, 11 Jul 1997 18:15:58 -0400

Date: Thu, 10 Jul 1997 12:46:04 +0530 (GMT+0530)
From: Chirayu Patel <>

I am currently developing a BSD sockets like interface within the Linux
kernel, so that it can be easier to embed application layer protocols
within the kernel. This will enable to make dedicated Linux servers,
dedicated for speed. (Please do not argue on this...I might be wrong...the
main purpose of this exercise to know more about the Linux kernel)

I suspect the reason why no one sent you a reply is becuase (a) you're
proposing to do something which most experienced kernel programmers
would say is a bad thing, and then (b) you said, please do not argue
with me on this.

So I said, "OK", and deleted your e-mail message.

The bottom line is that the kernel programming environment is very
different from the user programming environment; this is not surprising,
given that it is the kernel that provides services such as "signals".
So you don't have signal handlers in a kernel thread; kernel threads are
non-preemptible (this means that if a kernel thread gets into an
infinite loop, the entire system grinds to a halt). If you have kernel
code that wants to be "interrupted" by a signal, it is the kernel's code
responsibility to periodically check current->signal.

- Ted