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Date:   Wed, 13 Jul 2022 17:14:46 -0700
From:   Isaku Yamahata <isaku.yamahata@gmail.com>
To:     Kai Huang <kai.huang@intel.com>
Cc:     Isaku Yamahata <isaku.yamahata@gmail.com>,
        isaku.yamahata@intel.com, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, Paolo Bonzini <pbonzini@redhat.com>,
        Rick Edgecombe <rick.p.edgecombe@intel.com>
Subject: Re: [PATCH v7 033/102] KVM: x86/mmu: Add address conversion
 functions for TDX shared bits
Message-ID: <20220714001446.GR1379820@ls.amr.corp.intel.com>
References: <cover.1656366337.git.isaku.yamahata@intel.com>
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 <6cc36b662dffaf0aa2a2f389f073daa2d63a530b.camel@intel.com>
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On Wed, Jul 13, 2022 at 10:41:33PM +1200,
Kai Huang <kai.huang@intel.com> wrote:

> 
> > > 
> > > And by applying this patch, nothing will prevent you to turn on INTEL_TDX_HOST
> > > and KVM_INTEL, which also turns on KVM_MMU_PRIVATE.
> > > 
> > > So 'kvm_arch::gfn_shared_mask' is guaranteed to be 0?  If not, can legal
> > > (shared) GFN for normal VM be potentially treated as private?
> > > 
> > > If yes, perhaps explicitly call out in changelog so people don't need to worry
> > > about?
> > 
> > struct kvm that includes struct kvm_arch is guaranteed to be zero.
> > 
> > Here is the updated commit message.
> > 
> > Author: Isaku Yamahata <isaku.yamahata@intel.com>
> > Date:   Tue Jul 12 00:10:13 2022 -0700
> > 
> >     KVM: x86/mmu: Add address conversion functions for TDX shared bit of GPA
> >     
> >     TDX repurposes one GPA bit (51 bit or 47 bit based on configuration) to
> >     indicate the GPA is private(if cleared) or shared (if set) with VMM.  If
> >     GPA.shared is set, GPA is converted existing conventional EPT pointed by
> >     EPTP.  If GPA.shared bit is cleared, GPA is converted by TDX module.
> >     VMM has to issue SEAMCALLs to operate.
> 
> Sorry what does "GPA is converted ..." mean?

Oops. typo. I meant GPA is covered by ...

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