Explain TC class id limits
diff --git a/man/man8/tc.8 b/man/man8/tc.8
index a285c49..98fbfcd 100644
--- a/man/man8/tc.8
+++ b/man/man8/tc.8
@@ -24,7 +24,7 @@
.B tc filter [ add | change | replace | delete ] dev
DEV
-.B [ parent
+.B [ parent
qdisc-id
.B | root ] protocol
protocol
@@ -38,7 +38,7 @@
.RI "[ " FORMAT " ]"
.B qdisc show [ dev
DEV
-.B ]
+.B ]
.P
.B tc
.RI "[ " FORMAT " ]"
@@ -233,7 +233,10 @@
All qdiscs, classes and filters have IDs, which can either be specified
or be automatically assigned.
-IDs consist of a major number and a minor number, separated by a colon.
+ID's consist of a major number and a minor number, separated by a colon.
+Both major and minor number are limited to 16 bits. There are two special
+values: root is signified by major and minor of all ones, and unspecified
+is all zeros.
.TP
QDISCS
