diff --git a/man7/mq_overview.7 b/man7/mq_overview.7
index d8c1aca0b..5eff94b07 100644
--- a/man7/mq_overview.7
+++ b/man7/mq_overview.7
@@ -151,9 +151,7 @@ The default value for
 is 10.
 The minimum value is 1 (10 in kernels before 2.6.28).
 The upper limit is
-.BR HARD_MSGMAX :
-.IR "(131072\ /\ sizeof(void\ *))"
-(32768 on Linux/86).
+.BR HARD_MSGMAX .
 The
 .I msg_max
 limit is ignored for privileged processes
@@ -161,6 +159,17 @@ limit is ignored for privileged processes
 but the
 .BR HARD_MSGMAX
 ceiling is nevertheless imposed.
+The definition of
+.BR HARD_MSGMAX
+has changed across kernel versions:
+before Linux 2.6.33, it was
+.IR "(131072\ /\ sizeof(void\ *))"
+(32768 on Linux/86);
+from Linux 2.6.33, it was
+.IR "(32768\ *\ sizeof(void\ *)/4)" ;
+since Linux 3.5,
+.\" commit 5b5c4d1a1440e94994c73dddbad7be0676cd8b9a
+it is 65,536.
 .TP
 .I /proc/sys/fs/mqueue/msgsize_max
 This file can be used to view and change the ceiling on the