Re: [PATCH v11 016/113] KVM: TDX: Add place holder for TDX VM specific mem_enc_op ioctl

From: Isaku Yamahata
Date: Mon Feb 27 2023 - 16:22:11 EST


On Thu, Jan 19, 2023 at 02:40:17AM +0000,
"Huang, Kai" <kai.huang@xxxxxxxxx> 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@xxxxxxxxx>