diff --git a/man7/packet.7 b/man7/packet.7
index ecbd63409..3a833f7db 100644
--- a/man7/packet.7
+++ b/man7/packet.7
@@ -257,7 +257,9 @@ struct tpacket_auxdata {
     __u16 tp_mac;
     __u16 tp_net;
     __u16 tp_vlan_tci;
-    __u16 tp_vlan_tpid;
+    __u16 tp_vlan_tpid; /* Since Linux 3.14; earlier, these
+                           were unused padding bytes */
+.\" commit a0cdfcf39362410d5ea983f4daf67b38de129408 added tp_vlan_tpid
 };
 .EE
 .in