diff mbox series

[v4,08/24] KVM: nVMX: Ignore SIPI that arrives in L2 when vCPU is not in WFS

Message ID 20220723005137.1649592-9-seanjc@google.com (mailing list archive)
State New, archived
Headers show
Series KVM: x86: Event/exception fixes and cleanups | expand

Commit Message

Sean Christopherson July 23, 2022, 12:51 a.m. UTC 
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: bf0cd88ce363 ("KVM: x86: emulate wait-for-SIPI and SIPI-VMExit")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
---
 arch/x86/kvm/vmx/nested.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 6b4368d96d9e..46ea7740bb9e 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -3932,10 +3932,12 @@  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;
+			return 0;
+		}
+		/* Fallthrough, the SIPI is completely ignored. */
 	}
 
 	/*