From mboxrd@z Thu Jan  1 00:00:00 1970
From: Lai Jiangshan <laijs@cn.fujitsu.com>
Subject: Re: [RFC PATCH 2/2] kvm, x86: use ro page and don't copy shared page
Date: Thu, 10 Jun 2010 10:47:07 +0800
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Cc: Marcelo Tosatti <mtosatti@redhat.com>, kvm@vger.kernel.org
To: Avi Kivity <avi@redhat.com>
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Avi Kivity wrote:

> Wierd.  For what gfn/pfns does this trigger?
> 

It is ZERO_PAGE which also has Reserved bit, not mmio page.
The pte is set write-protected, I still don't know why it cause the system
hangup.

set_spte() {
	if (tdp_enabled)
		spte |= kvm_x86_ops->get_mt_mask(vcpu, gfn,
			kvm_is_mmio_pfn(pfn));

	/* guest can write to the page because of this statement? */
}