From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Date: Mon, 04 Aug 2008 22:02:49 +0000
Subject: Re: [BISECTION RESULT] sched: revert cpu_clock to
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To: tony.luck@intel.com
Cc: nacc@us.ibm.com, mingo@elte.hu, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org

From: "Luck, Tony" <tony.luck@intel.com>
Date: Mon, 4 Aug 2008 15:00:47 -0700

> > I'd bet resonable sums of money that we are (once again) accessing
> > per-cpu variables in code before ia64 has a chance to initialize
> > things so that they can actually work. :-(
> 
> I tried this simple hack to check ... per-cpu variables are
> not usable until cpu_init() sets up the "ar.k3" register on
> ia64.  So this hack checks to see if it is set before calling
> cpu_clock():

Can you guys on IA64 possibly set ar.k3 simply to zero or to some
other similar value which cancels out the per-cpu computation?

That's what sparc64 and other platforms do.