diff --git a/include/qemu/timer.h b/include/qemu/timer.h
index 39ea907e65f0957b227cd83c5cac4d72a6ab2b39..a005ed26922f4a36f3a4bb1a27073029c927e9d4 100644
--- a/include/qemu/timer.h
+++ b/include/qemu/timer.h
@@ -42,6 +42,14 @@
  * In icount mode, this clock counts nanoseconds while the virtual
  * machine is running.  It is used to increase @QEMU_CLOCK_VIRTUAL
  * while the CPUs are sleeping and thus not executing instructions.
+ *
+ * @QEMU_CLOCK_VIRTUAL_EXT: virtual clock for external subsystems
+ *
+ * The virtual clock only runs during the emulation. It stops
+ * when the virtual machine is stopped. The timers for this clock
+ * do not recorded in rr mode, therefore this clock could be used
+ * for the subsystems that operate outside the guest core.
+ *
  */
 
 typedef enum {
@@ -49,6 +57,7 @@ typedef enum {
     QEMU_CLOCK_VIRTUAL = 1,
     QEMU_CLOCK_HOST = 2,
     QEMU_CLOCK_VIRTUAL_RT = 3,
+    QEMU_CLOCK_VIRTUAL_EXT = 4,
     QEMU_CLOCK_MAX
 } QEMUClockType;
 
diff --git a/util/qemu-timer.c b/util/qemu-timer.c
index 86bfe84037ac400f0ea17a839c7d6bfd18090d3f..eb60d8f73a33a728a46e17f20bdfb293f6b941c5 100644
--- a/util/qemu-timer.c
+++ b/util/qemu-timer.c
@@ -496,6 +496,7 @@ bool timerlist_run_timers(QEMUTimerList *timer_list)
 
     switch (timer_list->clock->type) {
     case QEMU_CLOCK_REALTIME:
+    case QEMU_CLOCK_VIRTUAL_EXT:
         break;
     default:
     case QEMU_CLOCK_VIRTUAL:
@@ -597,6 +598,7 @@ int64_t qemu_clock_get_ns(QEMUClockType type)
         return get_clock();
     default:
     case QEMU_CLOCK_VIRTUAL:
+    case QEMU_CLOCK_VIRTUAL_EXT:
         if (use_icount) {
             return cpu_get_icount();
         } else {