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Date: Wed, 13 Aug 2008 18:25:53 +0200
From: Ingo Molnar <mingo@elte.hu>
To: "Luck, Tony" <tony.luck@intel.com>
Cc: Nishanth Aravamudan <nacc@us.ibm.com>,
       "linux-ia64@vger.kernel.org" <linux-ia64@vger.kernel.org>,
       LKML <linux-kernel@vger.kernel.org>
Subject: Re: [BISECTION RESULT] sched: revert cpu_clock to
	pre-27ec4407790d075c325e1f4da0a19c56953cce23 state
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* Luck, Tony <tony.luck@intel.com> wrote:

> > I'm happy to test any better patches.
> 
> Linus just took a patch from my tree that should solve this
> once and for all for ia64.
> 
> commit 10617bbe84628eb18ab5f723d3ba35005adde143
> Author: Tony Luck <tony.luck@intel.com>
> Date:   Tue Aug 12 10:34:20 2008 -0700
> 
>     [IA64] Ensure cpu0 can access per-cpu variables in early boot code
> 
> 
> When you get a chance please test with your config against this
> tree just to confirm that this is fixed.

there's also Peter's other patch upstream since yesterday (and included 
in -rc3) which should solve the same problem:

| commit c1955a3d4762e7a9bf84035eb3c4886a900f0d15
| Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
| Date:   Mon Aug 11 08:59:03 2008 +0200
|
|    sched_clock: delay using sched_clock()
|
|    Some arch's can't handle sched_clock() being called too early - delay
|    this until sched_clock_init() has been called.

so i'd be mighty surprised if this dual firepower of commits didnt at 
least weaken this bug somewhat! ;-)

	Ingo