Merge pull request FRRouting#16266 from FRRouting/mergify/bp/stable/9…

….1/pr-16252

zebra: fix evpn mh bond member proto reinstall (backport FRRouting#16252)

zebra/interface.c

@@ -1711,8 +1711,10 @@ static void interface_if_protodown(struct interface *ifp, bool protodown,
 				   uint32_t rc_bitfield)
 {
 	struct zebra_if *zif = ifp->info;
-	bool old_protodown;
+	bool old_protodown, reason_extern;
 
+	reason_extern = !!CHECK_FLAG(zif->protodown_rc,
+				     ZEBRA_PROTODOWN_EXTERNAL);
 	/*
 	 * Set our reason code to note it wasn't us.
 	 * If the reason we got from the kernel is ONLY frr though, don't
@@ -1728,8 +1730,8 @@ static void interface_if_protodown(struct interface *ifp, bool protodown,
 		return;
 
 	if (IS_ZEBRA_DEBUG_EVPN_MH_ES || IS_ZEBRA_DEBUG_DPLANE)
-		zlog_debug("interface %s dplane change, protodown %s",
-			   ifp->name, protodown ? "on" : "off");
+		zlog_debug("interface %s dplane change, protodown %s curr reason_extern %u",
+			   ifp->name, protodown ? "on" : "off", reason_extern);
 
 	/* Set protodown, respectively */
 	COND_FLAG(zif->flags, ZIF_FLAG_PROTODOWN, protodown);
@@ -1754,6 +1756,13 @@ static void interface_if_protodown(struct interface *ifp, bool protodown,
 			return;
 		}
 
+		if (!protodown && reason_extern) {
+			if (IS_ZEBRA_DEBUG_EVPN_MH_ES || IS_ZEBRA_DEBUG_KERNEL)
+				zlog_debug("bond member %s has protodown reason external and clear the reason, skip reinstall.",
+					   ifp->name);
+			return;
+		}
+
 		if (IS_ZEBRA_DEBUG_EVPN_MH_ES || IS_ZEBRA_DEBUG_KERNEL)
 			zlog_debug(
 				"bond mbr %s reinstate protodown %s in the dplane",