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Subject: Re: [PATCH 00/22] Introduce the TDP MMU
To:     Ben Gardon <bgardon@google.com>
Cc:     LKML <linux-kernel@vger.kernel.org>, kvm <kvm@vger.kernel.org>,
        Cannon Matthews <cannonmatthews@google.com>,
        Peter Xu <peterx@redhat.com>,
        Sean Christopherson <sean.j.christopherson@intel.com>,
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        Peter Feiner <pfeiner@google.com>,
        Junaid Shahid <junaids@google.com>,
        Jim Mattson <jmattson@google.com>,
        Yulei Zhang <yulei.kernel@gmail.com>,
        Wanpeng Li <kernellwp@gmail.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Xiao Guangrong <xiaoguangrong.eric@gmail.com>
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From:   Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <b6c18282-4fc7-5c66-9a34-f066823114e5@redhat.com>
Date:   Tue, 29 Sep 2020 20:10:07 +0200
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On 29/09/20 19:40, Ben Gardon wrote:
> I'll get to work responding to your comments and preparing a v2.

Please do respond to the comments, but I've actually already done most
of the changes (I'm bad at reviewing code without tinkering).  NX
recovery seems broken, but we can leave it out in the beginning as it's
fairly self contained.

I was going to post today, but I was undecided about whether to leave
out NX or try and fix it.

>> One feature that I noticed is missing is the shrinker.  What are your
>> plans (or opinions) around it?
> I assume by the shrinker you mean the page table quota that controls
> how many pages the MMU can use at a time to back guest memory?
> I think the shrinker is less important for the TDP MMU as there is an
> implicit limit on how much memory it will use to back guest memory.

Good point.  That's why I asked for opinions too.

Paolo