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Message-ID: <55fa888b31bae80bf72cbdbdf6f27401ea4ccc5c.camel@intel.com>
Subject: Re: [RFC PATCH v5 032/104] KVM: x86/mmu: introduce config for
 PRIVATE KVM MMU
From:   Kai Huang <kai.huang@intel.com>
To:     isaku.yamahata@intel.com, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org
Cc:     isaku.yamahata@gmail.com, Paolo Bonzini <pbonzini@redhat.com>,
        Jim Mattson <jmattson@google.com>, erdemaktas@google.com,
        Connor Kuehl <ckuehl@redhat.com>,
        Sean Christopherson <seanjc@google.com>
Date:   Fri, 01 Apr 2022 00:23:28 +1300
In-Reply-To: <770235e7fed04229b81c334e2477374374cea901.1646422845.git.isaku.yamahata@intel.com>
References: <cover.1646422845.git.isaku.yamahata@intel.com>
         <770235e7fed04229b81c334e2477374374cea901.1646422845.git.isaku.yamahata@intel.com>
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On Fri, 2022-03-04 at 11:48 -0800, isaku.yamahata@intel.com wrote:
> From: Isaku Yamahata <isaku.yamahata@intel.com>
> 
> To Keep the case of non TDX intact, introduce a new config option for
> private KVM MMU support.  At the moment, this is synonym for
> CONFIG_INTEL_TDX_HOST && CONFIG_KVM_INTEL.  The new flag make it clear
> that the config is only for x86 KVM MMU.
> 
> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
> ---
>  arch/x86/kvm/Kconfig | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
> index 2b1548da00eb..2db590845927 100644
> --- a/arch/x86/kvm/Kconfig
> +++ b/arch/x86/kvm/Kconfig
> @@ -136,4 +136,8 @@ config KVM_MMU_AUDIT
>  config KVM_EXTERNAL_WRITE_TRACKING
>  	bool
>  
> +config KVM_MMU_PRIVATE
> +	def_bool y
> +	depends on INTEL_TDX_HOST && KVM_INTEL
> +
>  endif # VIRTUALIZATION

I am really not sure why need this.  Roughly looking at MMU related patches this
new config option is hardly used.  You have many code changes related to
handling private/shared but they are not under this config option.

-- 
Thanks,
-Kai