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Date: Fri, 18 Sep 2009 16:38:33 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
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To: Oleg Nesterov <oleg@redhat.com>
cc: Wu Fei <at.wufei@gmail.com>, Ingo Molnar <mingo@elte.hu>,
       "Eric W. Biederman" <ebiederm@xmission.com>, arjan@infradead.org,
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       Andrew Morton <akpm@linux-foundation.org>,
       linux-tip-commits@vger.kernel.org,
       Rusty Russell <rusty@rustcorp.com.au>
Subject: Re: [PATCH 0/1] kthreads: simplify !kthreadd_task logic, kill
 kthreadd_task_init_done
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On Sat, 19 Sep 2009, Oleg Nesterov wrote:
>
> On 09/18, Linus Torvalds wrote:
> >
> > As to why pid == 0 wouldn't work, I don't know, but I'll take your word
> > for it.
> 
> Say, admin wants to renice kthreadd or change its affinity. And we can't
> show kthread in /proc if its pid is 0.

Ok, so it's a "that's not good" kind of situation, rather than a "it 
wouldn't work" one. Fair enough.

Of course, another way to do this would be to simply use CLONE_STOPPED to 
create the 'init' task first, but not wake it up - and then wake it up 
only after kthreadd exists.

I'm sure there are other things we could do ;)

		Linus