+This is rare, but does happen from time to time in real life. It is also
+possible for a zero-jiffy stall to be flagged in this case, depending
+on how the stall warning and the grace-period initialization happen to
+interact. Please note that it is not possible to entirely eliminate this
+sort of false positive without resorting to things like stop_machine(),
+which is overkill for this sort of problem.