Date:   Mon, 27 Feb 2023 13:22:00 -0800
From:   Isaku Yamahata <isaku.yamahata@gmail.com>
To:     "Huang, Kai" <kai.huang@intel.com>
Cc:     "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "Yamahata, Isaku" <isaku.yamahata@intel.com>,
        "pbonzini@redhat.com" <pbonzini@redhat.com>,
        "Shahar, Sagi" <sagis@google.com>,
        "Aktas, Erdem" <erdemaktas@google.com>,
        "isaku.yamahata@gmail.com" <isaku.yamahata@gmail.com>,
        "dmatlack@google.com" <dmatlack@google.com>,
        "Christopherson,, Sean" <seanjc@google.com>
Subject: Re: [PATCH v11 016/113] KVM: TDX: Add place holder for TDX VM
 specific mem_enc_op ioctl
Message-ID: <20230227212200.GE4175971@ls.amr.corp.intel.com>
References: <cover.1673539699.git.isaku.yamahata@intel.com>
 <e846968f2e1c554b3ecc1a876e0bb691727d34fc.1673539699.git.isaku.yamahata@intel.com>
 <19645255d65fdfd184b92b5192cac83a27c430fb.camel@intel.com>
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On Thu, Jan 19, 2023 at 02:40:17AM +0000,
"Huang, Kai" <kai.huang@intel.com> wrote:

> > diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
> > index 16053ec3e0ae..781fbc896120 100644
> > --- a/arch/x86/kvm/vmx/main.c
> > +++ b/arch/x86/kvm/vmx/main.c
> > @@ -37,6 +37,14 @@ static int vt_vm_init(struct kvm *kvm)
> >  	return vmx_vm_init(kvm);
> >  }
> >  
> > +static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
> > +{
> > +	if (!is_td(kvm))
> > +		return -ENOTTY;
> > +
> > +	return tdx_vm_ioctl(kvm, argp);
> > +}
> > +
> >  struct kvm_x86_ops vt_x86_ops __initdata = {
> >  	.name = KBUILD_MODNAME,
> >  
> > @@ -179,6 +187,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
> >  	.vcpu_deliver_sipi_vector = kvm_vcpu_deliver_sipi_vector,
> >  
> >  	.dev_mem_enc_ioctl = tdx_dev_ioctl,
> > +	.mem_enc_ioctl = vt_mem_enc_ioctl,
> >  };
> 
> IIUC, now both AMD and Intel have mem_enc_ioctl() callback implemented, so the
> KVM_X86_OP_OPTIONAL() of it can be changed to KVM_X86_OP(), and the function
> pointer check can be removed in the IOCTL:

Makes sense. Merged the following patch into the patch. Thanks for it.


> 
> diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-
> ops.h
> index 8dc345cc6318..a59852fb5e2a 100644
> --- a/arch/x86/include/asm/kvm-x86-ops.h
> +++ b/arch/x86/include/asm/kvm-x86-ops.h
> @@ -116,7 +116,7 @@ KVM_X86_OP(enter_smm)
>  KVM_X86_OP(leave_smm)
>  KVM_X86_OP(enable_smi_window)
>  #endif
> -KVM_X86_OP_OPTIONAL(mem_enc_ioctl)
> +KVM_X86_OP(mem_enc_ioctl)
>  KVM_X86_OP_OPTIONAL(mem_enc_register_region)
>  KVM_X86_OP_OPTIONAL(mem_enc_unregister_region)
>  KVM_X86_OP_OPTIONAL(vm_copy_enc_context_from)
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index c936f8d28a53..dfa279e35478 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -6937,10 +6937,6 @@ long kvm_arch_vm_ioctl(struct file *filp,
>                 goto out;
>         }
>         case KVM_MEMORY_ENCRYPT_OP: {
> -               r = -ENOTTY;
> -               if (!kvm_x86_ops.mem_enc_ioctl)
> -                       goto out;
> -
>                 r = static_call(kvm_x86_mem_enc_ioctl)(kvm, argp);
>                 break;
>         }
> 
> [snip]
> 

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