diff --git a/devicemodel/core/vmmapi.c b/devicemodel/core/vmmapi.c
index a01d61462..912004ddb 100644
--- a/devicemodel/core/vmmapi.c
+++ b/devicemodel/core/vmmapi.c
@@ -142,6 +142,7 @@ vm_create(const char *name, uint64_t req_buf)
 
 	if (lapic_pt) {
 		create_vm.vm_flag |= GUEST_FLAG_LAPIC_PASSTHROUGH;
+		create_vm.vm_flag |= GUEST_FLAG_RT;
 		create_vm.vm_flag |= GUEST_FLAG_IO_COMPLETION_POLLING;
 	} else {
 		create_vm.vm_flag &= (~GUEST_FLAG_LAPIC_PASSTHROUGH);
diff --git a/hypervisor/include/public/acrn_common.h b/hypervisor/include/public/acrn_common.h
index 814a6b702..d1caf062b 100644
--- a/hypervisor/include/public/acrn_common.h
+++ b/hypervisor/include/public/acrn_common.h
@@ -52,6 +52,7 @@
 #define GUEST_FLAG_IO_COMPLETION_POLLING	(1UL << 2U)  	/* Whether need hypervisor poll IO completion */
 #define GUEST_FLAG_CLOS_REQUIRED		(1UL << 3U)     /* Whether CLOS is required */
 #define GUEST_FLAG_HIDE_MTRR			(1UL << 4U)  	/* Whether hide MTRR from VM */
+#define GUEST_FLAG_RT				(1UL << 5U)     /* Whether the vm is RT-VM */
 
 /**
  * @brief Hypercall