It was initially added in r25762 by nbd.
SVN-Revision: 46825
+From: Felix Fietkau <nbd@openwrt.org>
+Subject: [PATCH] bridge: port isolate
+
+Isolating individual bridge ports
+---
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -172,6 +172,7 @@ struct net_bridge_port
+From: Felix Fietkau <nbd@openwrt.org>
+Subject: [PATCH] bridge: port isolate
+
+Isolating individual bridge ports
+---
--- a/include/linux/if_bridge.h
+++ b/include/linux/if_bridge.h
@@ -44,6 +44,7 @@ struct br_ip_list {
+From: Felix Fietkau <nbd@openwrt.org>
+Subject: [PATCH] bridge: port isolate
+
+Isolating individual bridge ports
+---
--- a/include/linux/if_bridge.h
+++ b/include/linux/if_bridge.h
@@ -45,6 +45,7 @@ struct br_ip_list {