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Date:   Thu, 15 Dec 2022 19:58:23 -0800
From:   Isaku Yamahata <isaku.yamahata@gmail.com>
To:     Binbin Wu <binbin.wu@linux.intel.com>
Cc:     isaku.yamahata@intel.com, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, isaku.yamahata@gmail.com,
        Paolo Bonzini <pbonzini@redhat.com>, erdemaktas@google.com,
        Sean Christopherson <seanjc@google.com>,
        Sagi Shahar <sagis@google.com>,
        David Matlack <dmatlack@google.com>
Subject: Re: [PATCH v10 106/108] Documentation/virt/kvm: Document on Trust
 Domain Extensions(TDX)
Message-ID: <20221216035823.GE527635@ls.amr.corp.intel.com>
References: <cover.1667110240.git.isaku.yamahata@intel.com>
 <fcf376f0f7703d06b6e7466e95cea624b58f746a.1667110240.git.isaku.yamahata@intel.com>
 <faf65da9-aeb4-d7b2-0e60-995848e47d14@linux.intel.com>
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On Fri, Nov 25, 2022 at 11:49:08AM +0800,
Binbin Wu <binbin.wu@linux.intel.com> wrote:

> > +New KVM API, ioctl (sub)command, to manage TD VMs
> > +-------------------------------------------------
> > +Additional KVM API
> API -> APIs
> >   are needed to control TD VMs. The operations on TD
> > +VMs are specific to TDX.
> > +
> > +- Piggyback and repurpose KVM_MEMORY_ENCRYPT_OP
> > +
> > +  Although not all operation isn't memory encryption,
> 
> How to understand it?
> 
> 
> > repupose to get

How about the followings?

New KVM API, ioctl (sub)command, to manage TD VMs
-------------------------------------------------
Additional KVM APIs are needed to control TD VMs. The operations on TD
VMs are specific to TDX.

- Piggyback and repurpose KVM_MEMORY_ENCRYPT_OP

  Although operations for TD VMs aren't necessarily related to memory
  encryption, define sub operations of KVM_MEMORY_ENCRYPT_OP for TDX specific
  ioctls.

  Pros:

  - No major change in common x86 KVM code.
  - Follows the SEV case.

  Cons:

  - The sub operations of KVM_MEMORY_ENCRYPT_OP aren't necessarily memory
    encryption, but operations on TD VMs.


-- 
Isaku Yamahata <isaku.yamahata@gmail.com>