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Date:   Mon, 7 Aug 2023 07:30:03 -0700
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Subject: Re: [PATCH v3 10/12] x86/virt/tdx: Wire up basic SEAMCALL functions
From:   Sean Christopherson <seanjc@google.com>
To:     Kai Huang <kai.huang@intel.com>
Cc:     "kirill.shutemov@linux.intel.com" <kirill.shutemov@linux.intel.com>,
        Dave Hansen <dave.hansen@intel.com>,
        "x86@kernel.org" <x86@kernel.org>, "bp@alien8.de" <bp@alien8.de>,
        "peterz@infradead.org" <peterz@infradead.org>,
        "hpa@zytor.com" <hpa@zytor.com>,
        "mingo@redhat.com" <mingo@redhat.com>,
        "tglx@linutronix.de" <tglx@linutronix.de>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "pbonzini@redhat.com" <pbonzini@redhat.com>,
        Isaku Yamahata <isaku.yamahata@intel.com>,
        "sathyanarayanan.kuppuswamy@linux.intel.com" 
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        "n.borisov.lkml@gmail.com" <n.borisov.lkml@gmail.com>
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On Mon, Aug 07, 2023, Kai Huang wrote:
> 
> > >  
> > > +config INTEL_TDX_HOST
> > > +	bool "Intel Trust Domain Extensions (TDX) host support"
> > > +	depends on CPU_SUP_INTEL
> > > +	depends on X86_64
> > > +	depends on KVM_INTEL
> > 
> > Hm. I expected KVM_INTEL to depend on CPU_SUP_INTEL, but apparently no.
> > Any reasons why?
> 
> Hmm.. Not sure :-)

Centuar and Zhaoxin CPUs also support VMX.

  commit 8f63aaf5c493c6502a058585cdfa3c71cdf8c44a
  Author: Sean Christopherson <seanjc@google.com>
  Date:   Fri Dec 20 20:45:13 2019 -0800

    KVM: VMX: Allow KVM_INTEL when building for Centaur and/or Zhaoxin CPUs
    
    Change the dependency for KVM_INTEL, i.e. KVM w/ VMX, from Intel CPUs to
    any CPU that supports the IA32_FEAT_CTL MSR and thus VMX functionality.
    This effectively allows building KVM_INTEL for Centaur and Zhaoxin CPUs.