1 files changed, 29 insertions, 3 deletions

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index c8bc9b4ac3283..89758be9c6a61 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -62,6 +62,7 @@
 #include <net/lwtunnel.h>
 #include <net/ip_tunnels.h>
 #include <net/l3mdev.h>
+#include <trace/events/fib6.h>
 
 #include <asm/uaccess.h>
 
@@ -404,6 +405,14 @@ static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
 	}
 }
 
+static bool __rt6_check_expired(const struct rt6_info *rt)
+{
+	if (rt->rt6i_flags & RTF_EXPIRES)
+		return time_after(jiffies, rt->dst.expires);
+	else
+		return false;
+}
+
 static bool rt6_check_expired(const struct rt6_info *rt)
 {
 	if (rt->rt6i_flags & RTF_EXPIRES) {
@@ -857,6 +866,9 @@ restart:
 	}
 	dst_use(&rt->dst, jiffies);
 	read_unlock_bh(&table->tb6_lock);
+
+	trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
+
 	return rt;
 
 }
@@ -1070,6 +1082,8 @@ redo_rt6_select:
 		read_unlock_bh(&table->tb6_lock);
 
 		rt6_dst_from_metrics_check(rt);
+
+		trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
 		return rt;
 	} else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
 			    !(rt->rt6i_flags & RTF_GATEWAY))) {
@@ -1093,6 +1107,8 @@ redo_rt6_select:
 			uncached_rt = net->ipv6.ip6_null_entry;
 
 		dst_hold(&uncached_rt->dst);
+
+		trace_fib6_table_lookup(net, uncached_rt, table->tb6_id, fl6);
 		return uncached_rt;
 
 	} else {
@@ -1117,6 +1133,7 @@ redo_rt6_select:
 			dst_release(&rt->dst);
 		}
 
+		trace_fib6_table_lookup(net, pcpu_rt, table->tb6_id, fl6);
 		return pcpu_rt;
 
 	}
@@ -1252,7 +1269,8 @@ static struct dst_entry *rt6_check(struct rt6_info *rt, u32 cookie)
 
 static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt, u32 cookie)
 {
-	if (rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
+	if (!__rt6_check_expired(rt) &&
+	    rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
 	    rt6_check((struct rt6_info *)(rt->dst.from), cookie))
 		return &rt->dst;
 	else
@@ -1272,7 +1290,8 @@ static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
 
 	rt6_dst_from_metrics_check(rt);
 
-	if ((rt->rt6i_flags & RTF_PCPU) || unlikely(dst->flags & DST_NOCACHE))
+	if (rt->rt6i_flags & RTF_PCPU ||
+	    (unlikely(dst->flags & DST_NOCACHE) && rt->dst.from))
 		return rt6_dst_from_check(rt, cookie);
 	else
 		return rt6_check(rt, cookie);
@@ -1322,6 +1341,12 @@ static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
 	rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
 }
 
+static bool rt6_cache_allowed_for_pmtu(const struct rt6_info *rt)
+{
+	return !(rt->rt6i_flags & RTF_CACHE) &&
+		(rt->rt6i_flags & RTF_PCPU || rt->rt6i_node);
+}
+
 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
 				 const struct ipv6hdr *iph, u32 mtu)
 {
@@ -1335,7 +1360,7 @@ static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
 	if (mtu >= dst_mtu(dst))
 		return;
 
-	if (rt6->rt6i_flags & RTF_CACHE) {
+	if (!rt6_cache_allowed_for_pmtu(rt6)) {
 		rt6_do_update_pmtu(rt6, mtu);
 	} else {
 		const struct in6_addr *daddr, *saddr;
@@ -1458,6 +1483,7 @@ out:
 
 	read_unlock_bh(&table->tb6_lock);
 
+	trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
 	return rt;
 };