From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wanpeng Li <wanpeng.li@linux.intel.com>
Subject: Re: EPT Accessed bit
Date: Wed, 13 Aug 2014 11:20:19 +0800
Message-ID: <20140813032019.GA32167@kernel>
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To: Umesh Deshpande <udeshpa1@binghamton.edu>
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Hi Umesh,
On Tue, Aug 12, 2014 at 08:07:48PM -0500, Umesh Deshpande wrote:
>Hi,
>
>>>From the Intel processor manual I read that accessed bit has been
>introduced in EPT. The Redhat 6 release notes mention that "Extended
>Page Table age bits enables a host to make smarter choices for
>swapping memory under memory pressure".  I couldn't find any related
>patches on KVM or LKML. I was wondering if using the EPT accessed bit
>requires any support from KVM to allow the host kernel to determine
>and swap out the inactive VM pages.
>

IIUC, host tracks the EPT A bit through mmu notifier.

Regards,
Wanpeng Li 

>Thanks,
>Umesh
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