Index: share/man/man9/rwlock.9
===================================================================
--- share/man/man9/rwlock.9
+++ share/man/man9/rwlock.9
@@ -24,7 +24,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd December 13, 2014
+.Dd March 18, 2016
 .Dt RWLOCK 9
 .Os
 .Sh NAME
@@ -324,7 +324,13 @@
 .Dv RA_LOCKED
 and
 .Dv RA_RLOCKED
-assertions merely check that some thread holds a read lock.
+assertions merely check that any thread holds a read lock.
+Similarly,
+.Dv RA_UNLOCKED
+in the
+.No non- Ns Dv WITNESS
+case is only able to assert that the current thread does not hold a write
+lock.
 .Pp
 Reader/writer is a bit of an awkward name.
 An
Index: share/man/man9/sx.9
===================================================================
--- share/man/man9/sx.9
+++ share/man/man9/sx.9
@@ -26,7 +26,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd March 16, 2016
+.Dd March 18, 2016
 .Dt SX 9
 .Os
 .Sh NAME
@@ -320,11 +320,21 @@
 .Xr rwlock 9 ,
 .Xr sema 9
 .Sh BUGS
+If
+.Dv WITNESS
+is not included in the kernel,
+then it is impossible to assert whether the current thread does or does not
+hold a shared lock.
 In the
 .No non- Ns Dv WITNESS
 case, the
 .Dv SA_LOCKED
 and
 .Dv SA_SLOCKED
-assertions merely check that some thread holds a shared lock.
-They do not ensure that the current thread holds a shared lock.
+assertions merely check whether any thread holds a shared lock.
+Similarly,
+.Dv SA_UNLOCKED
+in the
+.No non- Ns Dv WITNESS
+case is only able to assert that the current thread does not hold an exclusive
+lock.