diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index b724273493d8..365a70ec738e 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -12287,14 +12287,28 @@ static inline bool apf_pageready_slot_free(struct kvm_vcpu *vcpu) static bool kvm_can_deliver_async_pf(struct kvm_vcpu *vcpu) { - if (!vcpu->arch.apf.delivery_as_pf_vmexit && is_guest_mode(vcpu)) + + if (!kvm_pv_async_pf_enabled(vcpu)) return false; - if (!kvm_pv_async_pf_enabled(vcpu) || - (vcpu->arch.apf.send_user_only && static_call(kvm_x86_get_cpl)(vcpu) == 0)) + if (vcpu->arch.apf.send_user_only && + static_call(kvm_x86_get_cpl)(vcpu) == 0) return false; - return true; + if (is_guest_mode(vcpu)) { + /* + * L1 needs to opt into the special #PF vmexits that are + * used to deliver async page faults. + */ + return vcpu->arch.apf.delivery_as_pf_vmexit; + } else { + /* + * Play it safe in case the guest temporarily disables paging. + * The real mode IDT in particular is unlikely to have a #PF + * exception setup. + */ + return is_paging(vcpu); + } } bool kvm_can_do_async_pf(struct kvm_vcpu *vcpu)