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Date: Wed, 25 Jul 2007 10:55:52 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>, linux-kernel@vger.kernel.org,
       Linus Torvalds <torvalds@linux-foundation.org>, stable@kernel.org,
       Greg KH <greg@kroah.com>, Chris Wright <chrisw@sous-sol.org>
Subject: Re: [patch] fix the softlockup watchdog to actually work
Message-ID: <20070725085552.GA22965@elte.hu>
References: <20070717114453.GA8212@elte.hu> <469CCF8F.4010107@goop.org> <20070717154934.GA24231@elte.hu> <20070725014912.35c7e325.akpm@linux-foundation.org> <20070725085204.GA22067@elte.hu>
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* Ingo Molnar <mingo@elte.hu> wrote:

> > Still isn't working.  I'm getting random meaningless softlockup 
> > trippings coming out for no apparent reason.
> 
> hm, you still havent applied the other 4 patches i sent:
> 
>  softlockup-fix.patch
> 
>  softlockup-add-irq-regs-h.patch
>  softlockup-better-printout.patch
>  softlockup-cleanups.patch
>  softlockup-use-cpu-clock.patch
> 
> they are all necessary.
> 
> softlockup-use-cpu-clock.patch could easily solve the present problem 
> you have: as i pointed it out it is _wrong_ to use sched_clock(), 
> because sched_clock() is not a reliable clocksource. Especially on 
> your VAIO.

note: the cpu_clock() API is in v2.6.23-rc1 already so the above patches 
work fine as-is.

[ for -stable, my other patch should be used that restores jiffies use
  in softirq.c. ]

	Ingo