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Date: Thu, 16 Apr 2015 16:14:40 +0800
From: Wanpeng Li <wanpeng.li@linux.intel.com>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>,
        Andres Lagar-Cavilla <andreslc@google.com>,
        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
Message-ID: <20150416081440.GA3575@kernel>
Reply-To: Wanpeng Li <wanpeng.li@linux.intel.com>
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On Wed, Apr 15, 2015 at 05:05:48PM +0200, 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.

Reviewed-by: Wanpeng Li <wanpeng.li@linux.intel.com>