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From: Paolo Bonzini <pbonzini@redhat.com>
Date: Tue, 16 Apr 2024 19:52:08 +0200
Message-ID: <CABgObfbsZKRidj7P72suZRAKcNQiRwFb73hi8iELU_g7kvt4Ug@mail.gmail.com>
Subject: Re: [PATCH 07/10] KVM: VMX: Introduce test mode related to EPT
 violation VE
To: Chao Gao <chao.gao@intel.com>
Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, 
	Isaku Yamahata <isaku.yamahata@intel.com>
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On Mon, Apr 15, 2024 at 3:22=E2=80=AFPM Chao Gao <chao.gao@intel.com> wrote=
:
>
> >
> >-      if (cpu_has_secondary_exec_ctrls())
> >+      if (cpu_has_secondary_exec_ctrls()) {
> >               secondary_exec_controls_set(vmx, vmx_secondary_exec_contr=
ol(vmx));
> >+              if (secondary_exec_controls_get(vmx) &
> >+                  SECONDARY_EXEC_EPT_VIOLATION_VE) {
> >+                      if (!vmx->ve_info) {
>
> how about allocating ve_info in vmx_vcpu_create()? It is better to me bec=
ause:
>
> a. symmetry. ve_info is free'd in vmx_vcpu_free().
> b. no need to check if this is the first call of init_vmcs(). and ENOMEM =
can
> be returned on allocation failure.

There is no need to return ENOMEM however, it is okay to disable the test.

However I agree that doing it in vmx_vcpu_create(), conditional on
vmcs_config.cpu_based_2nd_exec_ctrl, is a bit cleaner.

Paolo