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Message-ID: <552F0480.6020106@linux.intel.com>
Date: Thu, 16 Apr 2015 08:38:24 +0800
From: Xiao Guangrong <guangrong.xiao@linux.intel.com>
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To: Paolo Bonzini <pbonzini@redhat.com>,
        Andres Lagar-Cavilla <andreslc@google.com>
CC: Wanpeng Li <wanpeng.li@linux.intel.com>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, Eric Northup <digitaleric@google.com>
Subject: Re: [PATCH] KVM: MMU: fix comment in kvm_mmu_zap_collapsible_spte
References: <1428046825-6905-1-git-send-email-wanpeng.li@linux.intel.com>	<CAJu=L59ogYcW_VGVXeEyjVY65ExNrr_P61TdnpdXuWe9cHEpNw@mail.gmail.com>	<552B1FC3.4070604@linux.intel.com> <CAJu=L5_=TSJxsJbcHC=uhmGY2wo+CAjBSPSoxZC0YoOQ=9UvXQ@mail.gmail.com> <552C91BA.1010703@linux.intel.com> <552E7E4C.5020804@redhat.com>
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On 04/15/2015 11:05 PM, Paolo Bonzini wrote:
>
>
>> -         * Only EPT supported for now; otherwise, one would need to
>> -         * find out efficiently whether the guest page tables are
>> -         * also using huge pages.
>> +         * We can not do huge page mapping for the indirect shadow
>> +         * page (sp) found on the last rmap (level = 1 ) since
>> +         * indirect sp is synced with the page table in guest and
>> +         * indirect sp->level = 1 means the guest page table is
>> +         * using 4K page size mapping.
>
> What about:
>
> +		 * We cannot do huge page mapping for indirect shadow pages,
> +		 * which are found on the last rmap (level = 1) when not using
> +		 * tdp; such shadow pages are synced with the page table in
> +		 * the guest, and the guest page table is using 4K page size
> +		 * mapping if the indirect sp has level = 1.

Yeah, much better. Thanks for your improvement, Paolo!