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Date: Mon, 9 Apr 2012 22:16:30 +0900
From: Takuya Yoshikawa <takuya.yoshikawa@gmail.com>
To: Avi Kivity <avi@redhat.com>
Cc: Xiao Guangrong <xiaoguangrong.eric@gmail.com>,
        Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>,
        Marcelo Tosatti <mtosatti@redhat.com>,
        LKML <linux-kernel@vger.kernel.org>, KVM <kvm@vger.kernel.org>
Subject: Re: [PATCH 09/13] KVM: MMU: get expected spte out of mmu-lock
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On Mon, 09 Apr 2012 15:28:47 +0300
Avi Kivity <avi@redhat.com> wrote:

> Ah, so it's protecting two paths at the same time: rmap.write_protect ->
> fast page fault, and lock(sptep) -> write protect.
> 
> The whole thing needs to be documented very carefully in locking.txt,
> otherwise mmu.c will be write-protected to everyone except you.

Before changing mmu_lock usage, better describe it in locking.txt.

I guess from mmu.c git history, it is already restricted to a few
people who can describe that.

	Takuya