Re: [PATCH MANUALSEL 5.15 3/9] KVM: VMX: clear vmx_x86_ops.sync_pir_to_irr if APICv is disabled

[Paolo Bonzini]

On 12/13/21 15:19, Sasha Levin wrote:
> From: Paolo Bonzini <pbonzini@xxxxxxxxxx>
>
> [ Upstream commit e90e51d5f01d2baae5dcce280866bbb96816e978 ]
>
> There is nothing to synchronize if APICv is disabled, since neither
> other vCPUs nor assigned devices can set PIR.ON.
>
> Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> ---
>   arch/x86/kvm/vmx/vmx.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
> index dacdf2395f01a..4e212f04268bb 100644
> --- a/arch/x86/kvm/vmx/vmx.c
> +++ b/arch/x86/kvm/vmx/vmx.c
> @@ -7776,10 +7776,10 @@ static __init int hardware_setup(void)
>   		ple_window_shrink = 0;
>   	}
>   
> -	if (!cpu_has_vmx_apicv()) {
> +	if (!cpu_has_vmx_apicv())
>   		enable_apicv = 0;
> +	if (!enable_apicv)
>   		vmx_x86_ops.sync_pir_to_irr = NULL;
> -	}
>   
>   	if (cpu_has_vmx_tsc_scaling()) {
>   		kvm_has_tsc_control = true;

Acked-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>