Re: is reparent_to_init a good thing to do?

Rob Landley
2001-10-10T09:12:50Z

On Tuesday 09 October 2001 12:13, Andrew Morton wrote:

> I think yes, more kernel threads need to use this function. Most
> particularly, threads which are parented by a userspace application
> and which can terminate. For example, the nfsd threads.
>
> Right now, it's probably the case that nfsd threads will turn
> into zombies when they terminate, *if* their parent is still
> running. But of course, most kernel threads are parented
> by very short-lived userspace applications, so nobody has
> ever noticed.

Or long lived kernel threads from short lived login sessions.

You have a headless gateway box for your local subnet, administered via ssh
from a machine on the local subnet. So you SSH into the box through eth1,
ifconfig eth0 down back up again. If eth0 is an rtl8039too, this fires off a
kernel thread (which, before reparent_to_init, was parented to your ssh login
session).

Now exit the login session. SSH does not exit until all the child processes
exit, so it just hangs there until you kill it from another console window...

Rob