--- zzzz-none-000/linux-4.4.60/Documentation/timers/timers-howto.txt	2017-04-08 07:53:53.000000000 +0000
+++ hawkeye-5590-729/linux-4.4.60/Documentation/timers/timers-howto.txt	2022-03-30 14:21:51.000000000 +0000
@@ -103,3 +103,6 @@
 			short, the difference is whether the sleep can be ended
 			early by a signal. In general, just use msleep unless
 			you know you have a need for the interruptible variant.
+
+	FLEXIBLE SLEEPING (any delay, uninterruptible)
+		* Use fsleep