From mboxrd@z Thu Jan  1 00:00:00 1970
From: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Subject: Re: [PATCH v5 11/14] nEPT: MMU context for nested EPT
Date: Thu, 01 Aug 2013 17:16:07 +0800
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Cc: kvm@vger.kernel.org, Jun Nakajima <jun.nakajima@intel.com>,
	Yang Zhang <yang.z.zhang@intel.com>, pbonzini@redhat.com
To: Gleb Natapov <gleb@redhat.com>
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On 07/31/2013 10:48 PM, Gleb Natapov wrote:
> From: Nadav Har'El <nyh@il.ibm.com>
> 
> KVM's existing shadow MMU code already supports nested TDP. To use it, we
> need to set up a new "MMU context" for nested EPT, and create a few callbacks
> for it (nested_ept_*()). This context should also use the EPT versions of
> the page table access functions (defined in the previous patch).
> Then, we need to switch back and forth between this nested context and the
> regular MMU context when switching between L1 and L2 (when L1 runs this L2
> with EPT).

This patch looks good to me.

Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>

But i am confused that update_permission_bitmask() is not adjusted in this
series. That function depends on kvm_read_cr4_bits(X86_CR4_SMEP) and
is_write_protection(), these two functions should read the registers from
L2 guest, using the L2 status to check L1's page table seems strange.
The same issue is in nested npt. Anything i missed?