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+--- Kernel support ---
+
+Currently, only context switch events are supported. The kernel events are
+usually written by the kernel into a buffer, without any action from user space.
+This behavior poses a problem, as the user space events and kernel events can
+leave a unsorted trace.
+
+The current workaround involves surounding the kernel events by two special ovni
+event markers OU[ and OU] which determine the region of events which must be
+sorted first. Notice that the events inside the region must be sorted!
+
+The `ovnisort` tool has been designed to sort the events enclosed by those
+markers by using a very simple window sorting algorithm, trying to insert them
+in order by looking only at the past 10000 events.
+
+To use the kernel events, you must sort the ovni trace before calling the
+emulator:
+
+	% ./application
+	% ovnisort ovni
+	% ovniemu ovni