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Date: Thu, 22 Jun 2006 21:25:52 +0100 (BST)
From: Hugh Dickins <hugh@veritas.com>
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To: Nick Piggin <nickpiggin@yahoo.com.au>
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       ashok.raj@intel.com, ak@suse.de, mingo@elte.hu
Subject: Re: [PATCH] stop on cpu lost
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On Fri, 23 Jun 2006, Nick Piggin wrote:
> > >Hugh Dickins wrote:
> > >
> > > >I'd expect tasks bound to the unplugged cpu simply not to be run
> > > >until "that" cpu is plugged back in.
> > 
> > I wasn't meaning "kill -9" for the swsusp case, but for the general
> > unplug cpu case.  We have a number of homeless tasks, which the admin
> > might want to run again when "the" cpu is plugged back in; or might
> > want to kill off without having to plug a cpu back in.
> 
> Possible maybe... I presumed that would lead to a nightmare of
> resource deadlocks (think mutexes).

Yes, that's what I've naively overlooked - thanks.

But _maybe_ there's still a case for allowing such tasks to run
_in_kernel_ on a wrong cpu, to release resources, and to be killed.

Hugh