From mboxrd@z Thu Jan  1 00:00:00 1970
From: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Subject: Re: [PATCH v2 07/22] KVM: MMU: cache mmio info on page fault path
Date: Wed, 29 Jun 2011 19:09:36 +0800
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Cc: Marcelo Tosatti <mtosatti@redhat.com>,
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To: Avi Kivity <avi@redhat.com>
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On 06/29/2011 04:48 PM, Avi Kivity wrote:
> On 06/22/2011 05:31 PM, Xiao Guangrong wrote:
>> If the page fault is caused by mmio, we can cache the mmio info, later, we do
>> not need to walk guest page table and quickly know it is a mmio fault while we
>> emulate the mmio instruction
> 
> Does this work if the mmio spans two pages?
> 

If the mmio spans two pages, we already split the emulation into two parts,
and the mmio cache info is only matched for one page, so i thinks it works
well :-)