static int __vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
{
	struct vcpu_vmx *vmx = to_vmx(vcpu);
	union vmx_exit_reason exit_reason = vmx->exit_reason;
	u32 vectoring_info = vmx->idt_vectoring_info;
	u16 exit_handler_index;

	/*
	 * Flush logged GPAs PML buffer, this will make dirty_bitmap more
	 * updated. Another good is, in kvm_vm_ioctl_get_dirty_log, before
	 * querying dirty_bitmap, we only need to kick all vcpus out of guest
	 * mode as if vcpus is in root mode, the PML buffer must has been
	 * flushed already.  Note, PML is never enabled in hardware while
	 * running L2.
	 */
	if (enable_pml && !is_guest_mode(vcpu))
		vmx_flush_pml_buffer(vcpu);

	/*
	 * We should never reach this point with a pending nested VM-Enter, and
	 * more specifically emulation of L2 due to invalid guest state (see
	 * below) should never happen as that means we incorrectly allowed a
	 * nested VM-Enter with an invalid vmcs12.
	 */
	WARN_ON_ONCE(vmx->nested.nested_run_pending);

	/* If guest state is invalid, start emulating */
	if (vmx->emulation_required)
		return handle_invalid_guest_state(vcpu);

	if (is_guest_mode(vcpu)) {
		/*
		 * PML is never enabled when running L2, bail immediately if a
		 * PML full exit occurs as something is horribly wrong.
		 */
		if (exit_reason.basic == EXIT_REASON_PML_FULL)
			goto unexpected_vmexit;

		/*
		 * The host physical addresses of some pages of guest memory
		 * are loaded into the vmcs02 (e.g. vmcs12's Virtual APIC
		 * Page). The CPU may write to these pages via their host
		 * physical address while L2 is running, bypassing any
		 * address-translation-based dirty tracking (e.g. EPT write
		 * protection).
		 *
		 * Mark them dirty on every exit from L2 to prevent them from
		 * getting out of sync with dirty tracking.
		 */
		nested_mark_vmcs12_pages_dirty(vcpu);

		if (nested_vmx_reflect_vmexit(vcpu))
			return 1;
	}

	if (exit_reason.failed_vmentry) {
		dump_vmcs();
		vcpu->run->exit_reason = KVM_EXIT_FAIL_ENTRY;
		vcpu->run->fail_entry.hardware_entry_failure_reason
			= exit_reason.full;
		vcpu->run->fail_entry.cpu = vcpu->arch.last_vmentry_cpu;
		return 0;
	}

	if (unlikely(vmx->fail)) {
		dump_vmcs();
		vcpu->run->exit_reason = KVM_EXIT_FAIL_ENTRY;
		vcpu->run->fail_entry.hardware_entry_failure_reason
			= vmcs_read32(VM_INSTRUCTION_ERROR);
		vcpu->run->fail_entry.cpu = vcpu->arch.last_vmentry_cpu;
		return 0;
	}

	/*
	 * Note:
	 * Do not try to fix EXIT_REASON_EPT_MISCONFIG if it caused by
	 * delivery event since it indicates guest is accessing MMIO.
	 * The vm-exit can be triggered again after return to guest that
	 * will cause infinite loop.
	 */
	if ((vectoring_info & VECTORING_INFO_VALID_MASK) &&
	    (exit_reason.basic != EXIT_REASON_EXCEPTION_NMI &&
	     exit_reason.basic != EXIT_REASON_EPT_VIOLATION &&
	     exit_reason.basic != EXIT_REASON_PML_FULL &&
	     exit_reason.basic != EXIT_REASON_APIC_ACCESS &&
	     exit_reason.basic != EXIT_REASON_TASK_SWITCH)) {
		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
		vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_DELIVERY_EV;
		vcpu->run->internal.ndata = 3;
		vcpu->run->internal.data[0] = vectoring_info;
		vcpu->run->internal.data[1] = exit_reason.full;
		vcpu->run->internal.data[2] = vcpu->arch.exit_qualification;
		if (exit_reason.basic == EXIT_REASON_EPT_MISCONFIG) {
			vcpu->run->internal.ndata++;
			vcpu->run->internal.data[3] =
				vmcs_read64(GUEST_PHYSICAL_ADDRESS);
		}
		vcpu->run->internal.data[vcpu->run->internal.ndata++] =
			vcpu->arch.last_vmentry_cpu;
		return 0;
	}

	if (unlikely(!enable_vnmi &&
		     vmx->loaded_vmcs->soft_vnmi_blocked)) {
		if (!vmx_interrupt_blocked(vcpu)) {
			vmx->loaded_vmcs->soft_vnmi_blocked = 0;
		} else if (vmx->loaded_vmcs->vnmi_blocked_time > 1000000000LL &&
			   vcpu->arch.nmi_pending) {
			/*
			 * This CPU don't support us in finding the end of an
			 * NMI-blocked window if the guest runs with IRQs
			 * disabled. So we pull the trigger after 1 s of
			 * futile waiting, but inform the user about this.
			 */
			printk(KERN_WARNING "%s: Breaking out of NMI-blocked "
			       "state on VCPU %d after 1 s timeout\n",
			       __func__, vcpu->vcpu_id);
			vmx->loaded_vmcs->soft_vnmi_blocked = 0;
		}
	}

	if (exit_fastpath != EXIT_FASTPATH_NONE)
		return 1;

	if (exit_reason.basic >= kvm_vmx_max_exit_handlers)
		goto unexpected_vmexit;
#ifdef CONFIG_RETPOLINE
	if (exit_reason.basic == EXIT_REASON_MSR_WRITE)
		return kvm_emulate_wrmsr(vcpu);
	else if (exit_reason.basic == EXIT_REASON_PREEMPTION_TIMER)
		return handle_preemption_timer(vcpu);
	else if (exit_reason.basic == EXIT_REASON_INTERRUPT_WINDOW)
		return handle_interrupt_window(vcpu);
	else if (exit_reason.basic == EXIT_REASON_EXTERNAL_INTERRUPT)
		return handle_external_interrupt(vcpu);
	else if (exit_reason.basic == EXIT_REASON_HLT)
		return kvm_emulate_halt(vcpu);
	else if (exit_reason.basic == EXIT_REASON_EPT_MISCONFIG)
		return handle_ept_misconfig(vcpu);
#endif

	exit_handler_index = array_index_nospec((u16)exit_reason.basic,
						kvm_vmx_max_exit_handlers);
	if (!kvm_vmx_exit_handlers[exit_handler_index])
		goto unexpected_vmexit;

	return kvm_vmx_exit_handlers[exit_handler_index](vcpu);

unexpected_vmexit:
	vcpu_unimpl(vcpu, "vmx: unexpected exit reason 0x%x\n",
		    exit_reason.full);
	dump_vmcs();
	vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
	vcpu->run->internal.suberror =
			KVM_INTERNAL_ERROR_UNEXPECTED_EXIT_REASON;
	vcpu->run->internal.ndata = 2;
	vcpu->run->internal.data[0] = exit_reason.full;
	vcpu->run->internal.data[1] = vcpu->arch.last_vmentry_cpu;
	return 0;
}
Unknown