From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: [PATCH 11/11] KVM: MMU: improve write flooding detected
Date: Thu, 25 Aug 2011 07:42:10 +0300
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Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>,
	LKML <linux-kernel@vger.kernel.org>, KVM <kvm@vger.kernel.org>
To: Marcelo Tosatti <mtosatti@redhat.com>
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On 08/25/2011 05:04 AM, Marcelo Tosatti wrote:
> >
> >  It could increase the flood count independently of the accessed bit of
> >  the spte being updated, zapping after 3 attempts as it is now.
> >
> >  But additionally reset the flood count if the gpte appears to be valid
> >  (points to an existant gfn if the present bit is set, or if its zeroed).
>
> Well not zero, as thats a common pattern for non ptes.
>

On 32-bit with 4GB RAM, practically anything is a valid gpte.

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.