trace_monitor_qmp_in_band_dequeue(req_obj,
req_obj->mon->qmp_requests->length);
- if (qatomic_xchg(&qmp_dispatcher_co_busy, true) == true) {
- /*
- * Someone rescheduled us (probably because a new requests
- * came in), but we didn't actually yield. Do that now,
- * only to be immediately reentered and removed from the
- * list of scheduled coroutines.
- */
- qemu_coroutine_yield();
- }
-
- /*
- * Move the coroutine from iohandler_ctx to qemu_aio_context for
- * executing the command handler so that it can make progress if it
- * involves an AIO_WAIT_WHILE().
- */
- aio_co_schedule(qemu_get_aio_context(), qmp_dispatcher_co);
- qemu_coroutine_yield();
-
/*
* @req_obj has a request, we hold req_obj->mon->qmp_queue_lock
*/
monitor_resume(&mon->common);
}
+ /*
+ * Drop the queue mutex now, before yielding, otherwise we might
+ * deadlock if the main thread tries to lock it.
+ */
qemu_mutex_unlock(&mon->qmp_queue_lock);
+ if (qatomic_xchg(&qmp_dispatcher_co_busy, true) == true) {
+ /*
+ * Someone rescheduled us (probably because a new requests
+ * came in), but we didn't actually yield. Do that now,
+ * only to be immediately reentered and removed from the
+ * list of scheduled coroutines.
+ */
+ qemu_coroutine_yield();
+ }
+
+ /*
+ * Move the coroutine from iohandler_ctx to qemu_aio_context for
+ * executing the command handler so that it can make progress if it
+ * involves an AIO_WAIT_WHILE().
+ */
+ aio_co_schedule(qemu_get_aio_context(), qmp_dispatcher_co);
+ qemu_coroutine_yield();
+
/* Process request */
if (req_obj->req) {
if (trace_event_get_state(TRACE_MONITOR_QMP_CMD_IN_BAND)) {