Re: [PATCH v5 10/12] x86/mtrr/main.c: Ask the first online CPU tosave mtrr

[H. Peter Anvin]

On 01/12/2012 04:33 AM, Brian Gerst wrote:
> On Wed, Jan 11, 2012 at 12:04 PM, Fenghua Yu <fenghua.yu@xxxxxxxxx> wrote:
>> From: Fenghua Yu <fenghua.yu@xxxxxxxxx>
>>
>> Ask the first online CPU to save mtrr instead of asking BSP. BSP could be
>> offline when mtrr_save_state() is called.
> 
> If you can use any non-boot cpu to save the MTRRs why not just use the
> current cpu?  They should all be in sync anyways.
> 

A much bigger question: why do we ever bother saving the MTRR state per
se?  We examine the MTRR state -- we have to -- during boot, and it
should never diverge from the state set by the OS from that point on --
we'll need to set it back to that.  So we should just keep track of what
the correct MTRR state is at all times.

	-hpa


-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.

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