Re: [PATCH] Hotplug CPU prep III: daemonize idle tasks

[Rusty Russell]

In message <[e-mail]> you write:
> I tried a version of __daemonize in 2.4. It panics in
> schedule()
> 
>         prepare_to_switch();
>         {
>                 struct mm_struct *mm = next->mm;
>                 struct mm_struct *oldmm = prev->active_mm;
>                 if (!mm) {
>                         if (next->active_mm) BUG();
> 
> I got hit by the BUG() in 2.4, I think prepare_to_switch has
> moved to specific archs in 2.5. A quick look showed that
> this issue no longer exists in 2.5.

Uhhh... there are many other problems if you are trying to do this on
a "live" process.  idle process creation is a special case because it
has never been run yet.

This is not a generic "daemonize this task" mechanism!
Rusty.
--
  Anyone who quotes me in their sig is an idiot. -- Rusty Russell.