Hello Paolo Bonzini,
The patch c9d40913ac5a: "KVM: x86: enable event window in
inject_pending_event" from May 22, 2020, leads to the following
static checker warning:
arch/x86/kvm/x86.c:10530 kvm_can_do_async_pf()
warn: signedness bug returning '(-16)'
arch/x86/kvm/x86.c
10516 bool kvm_can_do_async_pf(struct kvm_vcpu *vcpu)
10517 {
10518 if (unlikely(!lapic_in_kernel(vcpu) ||
10519 kvm_event_needs_reinjection(vcpu) ||
10520 vcpu->arch.exception.pending))
10521 return false;
10522
10523 if (kvm_hlt_in_guest(vcpu->kvm) && !kvm_can_deliver_async_pf(vcpu))
10524 return false;
10525
10526 /*
10527 * If interrupts are off we cannot even use an artificial
10528 * halt state.
10529 */
10530 return kvm_arch_interrupt_allowed(vcpu);
10531 }
The svm_nmi_allowed() used to return false because interrupts aren't
allowed but now it returns -EBUSY so it returns true/allowed.
regards,
dan carpenter
