From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH v3 1/4] KVM: nVMX: Rework interception of IRQs and NMIs
Date: Fri, 07 Mar 2014 20:48:00 +0100
Message-ID: <531A2270.6010406@redhat.com>
References: <cover.1394218994.git.jan.kiszka@siemens.com> <c5b0a3c53c6d19092d1313fc7a6e807031ea9054.1394218994.git.jan.kiszka@siemens.com>
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Cc: kvm <kvm@vger.kernel.org>
To: Jan Kiszka <jan.kiszka@siemens.com>,
	Gleb Natapov <gleb@kernel.org>,
	Marcelo Tosatti <mtosatti@redhat.com>
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Il 07/03/2014 20:03, Jan Kiszka ha scritto:
> @@ -4631,22 +4631,8 @@ static void vmx_set_nmi_mask(struct kvm_vcpu *vcpu, bool masked)
>
>  static int vmx_nmi_allowed(struct kvm_vcpu *vcpu)
>  {
> -	if (is_guest_mode(vcpu)) {
> -		if (to_vmx(vcpu)->nested.nested_run_pending)
> -			return 0;
> -		if (nested_exit_on_nmi(vcpu)) {
> -			nested_vmx_vmexit(vcpu, EXIT_REASON_EXCEPTION_NMI,
> -					  NMI_VECTOR | INTR_TYPE_NMI_INTR |
> -					  INTR_INFO_VALID_MASK, 0);
> -			/*
> -			 * The NMI-triggered VM exit counts as injection:
> -			 * clear this one and block further NMIs.
> -			 */
> -			vcpu->arch.nmi_pending = 0;
> -			vmx_set_nmi_mask(vcpu, true);
> -			return 0;
> -		}
> -	}
> +	if (to_vmx(vcpu)->nested.nested_run_pending)
> +		return 0;
>
>  	if (!cpu_has_virtual_nmis() && to_vmx(vcpu)->soft_vnmi_blocked)
>  		return 0;
> @@ -4658,19 +4644,8 @@ static int vmx_nmi_allowed(struct kvm_vcpu *vcpu)
>
>  static int vmx_interrupt_allowed(struct kvm_vcpu *vcpu)
>  {
> -	if (is_guest_mode(vcpu)) {
> -		if (to_vmx(vcpu)->nested.nested_run_pending)
> -			return 0;
> -		if (nested_exit_on_intr(vcpu)) {
> -			nested_vmx_vmexit(vcpu, EXIT_REASON_EXTERNAL_INTERRUPT,
> -					  0, 0);
> -			/*
> -			 * fall through to normal code, but now in L1, not L2
> -			 */
> -		}
> -	}
> -
> -	return (vmcs_readl(GUEST_RFLAGS) & X86_EFLAGS_IF) &&
> +	return (!to_vmx(vcpu)->nested.nested_run_pending &&
> +		vmcs_readl(GUEST_RFLAGS) & X86_EFLAGS_IF) &&
>  		!(vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) &
>  			(GUEST_INTR_STATE_STI | GUEST_INTR_STATE_MOV_SS));

The checks on nested_run_pending are not needed anymore and can be 
replaced with a WARN_ON.  Otherwise,

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>

Paolo