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Message-ID: <6bffcb0e0703261050i7e89607fo32f825b79821e5ea@mail.gmail.com>
Date: Mon, 26 Mar 2007 19:50:41 +0200
From: "Michal Piotrowski" <michal.k.k.piotrowski@gmail.com>
To: "Ingo Molnar" <mingo@elte.hu>
Subject: Re: [patch] hrtimers debug patch
Cc: "Nick Piggin" <npiggin@suse.de>,
       "Linus Torvalds" <torvalds@linux-foundation.org>,
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       "Andrew Morton" <akpm@linux-foundation.org>,
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On 26/03/07, Ingo Molnar <mingo@elte.hu> wrote:
>
> * Michal Piotrowski <michal.k.k.piotrowski@gmail.com> wrote:
>
> > Stardust is down, console log and config attached.
>
> thanks! I have stared at hrtimer.c a few more hours and the good news is
> that i found a narrow SMP race. The bad news is that i dont think it
> could explain your bug symptoms: the worst-case effect of the race
> should be an incorrect timeout on the current CPU - not a KTIME_MAX
> thing like your logs show.
>
> But maybe i didnt think through the effects of the bug well enough, and
> your box has a HT CPU, with HT CPUs being pretty good at triggering
> narrow SMP races - so maybe we are lucky? Fix attached below. Patch is
> build and boot-tested.

Thanks. Verification may take some time.

>
>         Ingo
>

Regards,
Michal

-- 
Michal K. K. Piotrowski
LTG - Linux Testers Group (PL)
(http://www.stardust.webpages.pl/ltg/)
LTG - Linux Testers Group (EN)
(http://www.stardust.webpages.pl/linux_testers_group_en/)