Re: [PATCH v2 15/28] KVM: VMX: Check CPU_BASED_{INTR,NMI}_WINDOW_EXITING in setup_vmcs_config()

[Vitaly Kuznetsov]

Jim Mattson <jmattson@xxxxxxxxxx> writes:

> On Wed, Jun 29, 2022 at 8:07 AM Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> wrote:
>>
>> CPU_BASED_{INTR,NMI}_WINDOW_EXITING controls are toggled dynamically by
>> vmx_enable_{irq,nmi}_window, handle_interrupt_window(), handle_nmi_window()
>> but setup_vmcs_config() doesn't check their existence. Add the check and
>> filter the controls out in vmx_exec_control().
>>
>> No (real) functional change intended as all existing CPUs supporting
>> VMX are supposed to have these controls.
>
> I'm pretty sure vIrtual NMIs and NMI-window exiting are not available
> on Prescott or Yonah.
>

I seemed to have questioned their existence :-) But you're right, I
should've said something like "all CPUs supported by KVM" instead (as
pre-patch KVM toggles these controls unconditionally).

>> Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
> Reviewed-by: Jim Mattson <jmattson@xxxxxxxxxx>
>

Thanks!

-- 
Vitaly