From 5025c0849fa769ef2e18c76dc10773f82e15a705 Mon Sep 17 00:00:00 2001
From: Hannes Reinecke <hare@suse.de>
Date: Wed, 6 Oct 2010 10:41:39 +0200
Subject: [PATCH] lldpad: fix for missing or dropped link events

netlink messages may be dropped. This patch adds a case
to handle a dropped link down event that was previously
not being detected. This resulted in the dcbx module
never running the ifup() routine so dcbx would not be
negotiated.

This is fatal if booting from remote FCoE disks that
require DCB to be negotiated.

References: bnc#637951

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Eric Multanen <eric.w.multanen@intel.com>
Acked-by: Hannes Reinecke <hare@suse.de>

diff --git a/config.c b/config.c
index 5cfac83..4875cb3 100644
--- a/config.c
+++ b/config.c
@@ -50,6 +50,7 @@
 #include "config.h"
 #include "clif_msgs.h"
 #include "lldp/l2_packet.h"
+#include "lldp_mod.h"
 
 config_t lldpad_cfg;
 static int cfg_loaded = false;
@@ -151,10 +152,22 @@ void scan_port(void *eloop_data, void *user_ctx)
 	 */
 	p = nameidx;
 	while (p->if_index != 0) {
-		if (is_valid_lldp_device(p->if_name) &&
-		    check_link_status(p->if_name) > 0) {
-			oper_add_device(p->if_name);
-			set_hw_all(p->if_name);
+		struct lldp_module *np;
+		const struct lldp_mod_ops *ops;
+		char *ifname = p->if_name;
+
+		if (is_valid_lldp_device(ifname)) {
+			if (check_link_status(ifname)) {
+				oper_add_device(ifname);
+				set_hw_all(ifname);
+			} else {
+				LIST_FOREACH(np, &lldp_head, lldp) {
+					ops = np->ops;
+					if (ops->lldp_mod_ifdown)
+						ops->lldp_mod_ifdown(ifname);
+				}
+				set_lldp_port_enable_state(ifname, 0);
+			}
 		}
 		p++;
 	}
diff --git a/event_iface.c b/event_iface.c
index 439e4d0..20af82e 100644
--- a/event_iface.c
+++ b/event_iface.c
@@ -117,13 +117,12 @@ int oper_add_device(char *device_name)
 	} else if (!port->portEnabled)
 		reinit_port(device_name);
 
-	if (!port || !port->portEnabled) {
-		LIST_FOREACH(np, &lldp_head, lldp) {
-			ops = np->ops;
-			if (ops->lldp_mod_ifup)
-				ops->lldp_mod_ifup(device_name);
-		}
+	LIST_FOREACH(np, &lldp_head, lldp) {
+		ops = np->ops;
+		if (ops->lldp_mod_ifup)
+			ops->lldp_mod_ifup(device_name);
 	}
+
 	set_lldp_port_enable_state(device_name, 1);
 	return 0;
 }
@@ -242,9 +241,7 @@ static void event_iface_receive(int sock, void *eloop_ctx, void *sock_ctx)
 
 	if (result < 0) {
 		perror("recvfrom(Event interface)");
-		if ((errno == ENOBUFS) || (errno == EAGAIN))
-			eloop_register_timeout(INI_TIMER, 0, scan_port,
-					       NULL, NULL);
+		eloop_register_timeout(INI_TIMER, 0, scan_port, NULL, NULL);
 		return;
 	}
 
diff --git a/lldp_dcbx.c b/lldp_dcbx.c
index 443f277..218c21d 100644
--- a/lldp_dcbx.c
+++ b/lldp_dcbx.c
@@ -452,7 +452,7 @@ void dcbx_ifup(char *ifname)
 	dud = find_module_user_data_by_if(ifname, &lldp_head, LLDP_MOD_DCBX);
 	tlvs = dcbx_data(ifname);	
 
-	if (!port || !check_port_dcb_mode(ifname)) 
+	if (!port || tlvs || !check_port_dcb_mode(ifname)) 
 		return;
 
 	/* if no adminStatus setting or wrong setting for adminStatus,
@@ -540,6 +540,9 @@ void dcbx_ifdown(char *device_name)
 
 	tlvs = dcbx_data(device_name);
 
+	if (!tlvs)
+		return;
+
 	/* remove dcb port */
 	if (check_port_dcb_mode(device_name)) {
 		dcbx_remove_adapter(device_name);
diff --git a/lldpad.c b/lldpad.c
index a89b5a4..a41f727 100644
--- a/lldpad.c
+++ b/lldpad.c
@@ -384,8 +384,6 @@ int main(int argc, char *argv[])
 		exit(1);
 	}
 
-	ctrl_iface_register(clifd);
-
 	/* Find available interfaces, read in the lldpad.conf file and
 	 * add adapters */
 	init_ports();
@@ -399,6 +397,8 @@ int main(int argc, char *argv[])
 		exit(1);
 	}
 
+	ctrl_iface_register(clifd);
+
 	LLDPAD_WARN("%s is starting", argv[0]);
 	eloop_run();
 	LLDPAD_WARN("%s is stopping", argv[0]);