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Message-ID: <b647ffbd0803141547s55fa37a1j5af4e50388d3117f@mail.gmail.com>
Date: Fri, 14 Mar 2008 23:47:05 +0100
From: "Dmitry Adamushko" <dmitry.adamushko@gmail.com>
To: "Hiroshi Shimamoto" <h-shimamoto@ct.jp.nec.com>
Subject: Re: [PATCH] sched: fix race in schedule
Cc: "Peter Zijlstra" <peterz@infradead.org>, "Ingo Molnar" <mingo@elte.hu>,
       linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org,
       hpj@urpla.net, stable <stable@kernel.org>
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On 14/03/2008, Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> wrote:
>
> [ ... ]
>
>  >> But maybe there is something esle that would be exposed by the
>  >> 'rq->curr = rq->idle' manipulation... I can't provide examples right
>  >> now though (I need to think on it).
>  >
>  > I share your concerns, I don't really like it either. Just spewing out
>  > ideas here - bad ideas it seems :-/
>  >
>  > Ingo also suggested moving the balance calls right before
>  > deactivate_task(), but that gives a whole other set of head-aches.
>  >
>
>
> Well, what will we do about this issue?
>  I see you're thinking to fix inconsistency in scheduler, right?
>  I agree about it.
>
>  However, I don't think it's good to remain this issue long time in
>  the -stable kernel.
>
>  Could you please let me know what I can do?

IMHO, the safest solution for the time being (and esp. for -stable)
would be to proceed with Hiroshi's patch. It looks safe and it does
fix a real problem.


>
> Hiroshi Shimamoto
>

-- 
Best regards,
Dmitry Adamushko
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