Commit 55714cdd authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

KVM: nSVM: Move SMI vmexit handling to svm_check_nested_events() 



Unlike VMX, SVM allows a hypervisor to take a SMI vmexit without having
any special SMM-monitor enablement sequence.  Therefore, it has to be
handled like interrupts and NMIs.  Check for an unblocked SMI in
svm_check_nested_events() so that pending SMIs are correctly prioritized
over IRQs and NMIs when the latter events will trigger VM-Exit.

Note that there is no need to test explicitly for SMI vmexits, because
guests always runs outside SMM and therefore can never get an SMI while
they are blocked.

Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent bbdad0b5

arch/x86/kvm/svm/nested.c

+16 −0
Original line number Diff line number Diff line
@@ -799,6 +799,15 @@ int nested_svm_check_exception(struct vcpu_svm *svm, unsigned nr, 
	return vmexit;

}



static void nested_svm_smi(struct vcpu_svm *svm)

{

	svm->vmcb->control.exit_code = SVM_EXIT_SMI;

	svm->vmcb->control.exit_info_1 = 0;

	svm->vmcb->control.exit_info_2 = 0;



	nested_svm_vmexit(svm);

}



static void nested_svm_nmi(struct vcpu_svm *svm)

{

	svm->vmcb->control.exit_code = SVM_EXIT_NMI;
@@ -831,6 +840,13 @@ static int svm_check_nested_events(struct kvm_vcpu *vcpu) 
		kvm_event_needs_reinjection(vcpu) || svm->nested.exit_required ||

		svm->nested.nested_run_pending;



	if (vcpu->arch.smi_pending && nested_exit_on_smi(svm)) {

		if (block_nested_events)

			return -EBUSY;

		nested_svm_smi(svm);

		return 0;

	}



	if (vcpu->arch.nmi_pending && nested_exit_on_nmi(svm)) {

		if (block_nested_events)

			return -EBUSY;

arch/x86/kvm/svm/svm.c

+0 −8
Original line number Diff line number Diff line
@@ -3778,14 +3778,6 @@ static bool svm_smi_allowed(struct kvm_vcpu *vcpu) 
	if (!gif_set(svm))

		return false;



	if (is_guest_mode(&svm->vcpu) &&

	    svm->nested.intercept & (1ULL << INTERCEPT_SMI)) {

		/* TODO: Might need to set exit_info_1 and exit_info_2 here */

		svm->vmcb->control.exit_code = SVM_EXIT_SMI;

		svm->nested.exit_required = true;

		return false;

	}



	return !is_smm(vcpu);

}

arch/x86/kvm/svm/svm.h

+5 −0
Original line number Diff line number Diff line
@@ -378,6 +378,11 @@ static inline bool svm_nested_virtualize_tpr(struct kvm_vcpu *vcpu) 
	return is_guest_mode(vcpu) && (vcpu->arch.hflags & HF_VINTR_MASK);

}



static inline bool nested_exit_on_smi(struct vcpu_svm *svm)

{

	return (svm->nested.intercept & (1ULL << INTERCEPT_SMI));

}



static inline bool nested_exit_on_nmi(struct vcpu_svm *svm)

{

	return (svm->nested.intercept & (1ULL << INTERCEPT_NMI));

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