From mboxrd@z Thu Jan  1 00:00:00 1970
From: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Subject: Re: [PATCH 1/5] KVM: vmx: fix ept reserved bits for 1-GByte page
Date: Mon, 18 Aug 2014 18:52:10 +0800
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Cc: Gleb Natapov <gleb@kernel.org>, hpa@zytor.com, x86@kernel.org,
	kvm@vger.kernel.org, linux-kernel@vger.kernel.org
To: Wanpeng Li <wanpeng.li@linux.intel.com>,
	Paolo Bonzini <pbonzini@redhat.com>
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On 08/18/2014 05:50 PM, Wanpeng Li wrote:
> EPT misconfig handler in kvm will check which reason lead to EPT 
> misconfiguration after vmexit. One of the reasons is that an EPT 
> paging-structure entry is configured with settings reserved for 
> future functionality. However, the handler can't identify if 
> paging-structure entry of reserved bits for 1-GByte page are 
> configured, since PDPTE which point to 1-GByte page will reserve 
> bits 29:12 instead of bits 7:3 which are reserved for PDPTE that 
> references an EPT Page Directory. This patch fix it by reserve 
> bits 29:12 for 1-GByte page. 

That mask is only set in the lowest pte for 4K page, i think it
is not a problem, no?