Commit c2086eca authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
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KVM: nVMX: Ignore SIPI that arrives in L2 when vCPU is not in WFS 



Fall through to handling other pending exception/events for L2 if SIPI
is pending while the CPU is not in Wait-for-SIPI.  KVM correctly ignores
the event, but incorrectly returns immediately, e.g. a SIPI coincident
with another event could lead to KVM incorrectly routing the event to L1
instead of L2.

Fixes: bf0cd88c ("KVM: x86: emulate wait-for-SIPI and SIPI-VMExit")
Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Reviewed-by: default avatarMaxim Levitsky <mlevitsk@redhat.com>
Link: https://lore.kernel.org/r/20220830231614.3580124-11-seanjc@google.com


Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 0701ec90

arch/x86/kvm/vmx/nested.c

+4 −2
Original line number Diff line number Diff line
@@ -3978,11 +3978,13 @@ static int vmx_check_nested_events(struct kvm_vcpu *vcpu) 
			return -EBUSY;



		clear_bit(KVM_APIC_SIPI, &apic->pending_events);

		if (vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED)

		if (vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED) {

			nested_vmx_vmexit(vcpu, EXIT_REASON_SIPI_SIGNAL, 0,

						apic->sipi_vector & 0xFFUL);

			return 0;

		}

		/* Fallthrough, the SIPI is completely ignored. */

	}



	/*

	 * Process exceptions that are higher priority than Monitor Trap Flag: