Commit 81601495 authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
Browse files

KVM: x86: Use kvm_queue_exception_e() to queue #DF 



Queue #DF by recursing on kvm_multiple_exception() by way of
kvm_queue_exception_e() instead of open coding the behavior.  This will
allow KVM to Just Work when a future commit moves exception interception
checks (for L2 => L1) into kvm_multiple_exception().

No functional change intended.

Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Reviewed-by: default avatarMaxim Levitsky <mlevitsk@redhat.com>
Link: https://lore.kernel.org/r/20220830231614.3580124-17-seanjc@google.com


Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 72c14e00

arch/x86/kvm/x86.c

+9 −12
Original line number Diff line number Diff line
@@ -667,26 +667,23 @@ static void kvm_multiple_exception(struct kvm_vcpu *vcpu, 
	}

	class1 = exception_class(prev_nr);

	class2 = exception_class(nr);

	if ((class1 == EXCPT_CONTRIBUTORY && class2 == EXCPT_CONTRIBUTORY)

		|| (class1 == EXCPT_PF && class2 != EXCPT_BENIGN)) {

	if ((class1 == EXCPT_CONTRIBUTORY && class2 == EXCPT_CONTRIBUTORY) ||

	    (class1 == EXCPT_PF && class2 != EXCPT_BENIGN)) {

		/*

		 * Generate double fault per SDM Table 5-5.  Set

		 * exception.pending = true so that the double fault

		 * can trigger a nested vmexit.

		 * Synthesize #DF.  Clear the previously injected or pending

		 * exception so as not to incorrectly trigger shutdown.

		 */

		vcpu->arch.exception.pending = true;

		vcpu->arch.exception.injected = false;

		vcpu->arch.exception.has_error_code = true;

		vcpu->arch.exception.vector = DF_VECTOR;

		vcpu->arch.exception.error_code = 0;

		vcpu->arch.exception.has_payload = false;

		vcpu->arch.exception.payload = 0;

	} else

		vcpu->arch.exception.pending = false;



		kvm_queue_exception_e(vcpu, DF_VECTOR, 0);

	} else {

		/* replace previous exception with a new one in a hope

		   that instruction re-execution will regenerate lost

		   exception */

		goto queue;

	}

}



void kvm_queue_exception(struct kvm_vcpu *vcpu, unsigned nr)

{