ipv6: Warn users if maximum number of routes is reached.

This gives users at least some clue as to what the problem
might be and how to go about fixing it.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 1 deletions

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index fc328339be99..96455ffb76fb 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -1945,8 +1945,12 @@ struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
         struct rt6_info *rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops);
         struct neighbour *neigh;
 
-        if (rt == NULL)
+        if (rt == NULL) {
+                if (net_ratelimit())
+                        pr_warning("IPv6:  Maximum number of routes reached,"
+                                   " consider increasing route/max_size.\n");
                 return ERR_PTR(-ENOMEM);
+        }
 
         dev_hold(net->loopback_dev);
         in6_dev_hold(idev);