From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.fraser@eu.citrix.com>
Subject: Re: please revert c/s 17686
Date: Fri, 13 Jun 2008 09:24:44 +0100
Message-ID: <C477ED5C.19C30%keir.fraser@eu.citrix.com>
References: <48524817.76E4.0078.0@novell.com>
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To: Jan Beulich <jbeulich@novell.com>, Gang Wei <gang.wei@intel.com>, xen-devel@lists.xensource.com
Cc: Ke Yu <ke.yu@intel.com>
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On 13/6/08 09:12, "Jan Beulich" <jbeulich@novell.com> wrote:

>>> I missed that warning printk. It does indeed look odd.
>> 
>> As to this warning printk, we can simply replace it with an assert.
> 
> That would make things worse, not better - the condition simply must be
> allowed (as said before, otherwise you won't be able to bring all CPUs
> at once into C3).

I think that C2/C3 are entered with IRQs disabled, but IRQ pending will kick
the CPU out of C2/C3 nonetheless. That CPU will then execute
hpet_broadcast_exit() before local_irq_enable() and hence the warning printk
will never actually fire. So it would be correct as a BUG_ON().

Is this correct, Wei?

 -- Keir