From: Timo Teräs Date: Wed, 26 Feb 2014 09:43:04 +0000 (+0200) Subject: neigh: probe application via netlink in NUD_PROBE X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=a960ff81f0cd6390940faa75a078ac76acec7940;p=openwrt%2Fstaging%2Fblogic.git neigh: probe application via netlink in NUD_PROBE iproute2 arpd seems to expect this as there's code and comments to handle netlink probes with NUD_PROBE set. It is used to flush the arpd cached mappings. opennhrp instead turns off unicast probes (so it can handle all neighbour discovery). Without this change it will not see NUD_PROBE probes and cannot reconfirm the mapping. Thus currently neigh entry will just fail and can cause few packets dropped until broadcast discovery is restarted. Earlier discussion on the subject: http://marc.info/?t=139305877100001&r=1&w=2 Signed-off-by: Timo Teräs Signed-off-by: David S. Miller --- diff --git a/net/core/neighbour.c b/net/core/neighbour.c index b9e9e0d38672..36d3f8c1a2dd 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -836,10 +836,10 @@ out: static __inline__ int neigh_max_probes(struct neighbour *n) { struct neigh_parms *p = n->parms; - return (n->nud_state & NUD_PROBE) ? - NEIGH_VAR(p, UCAST_PROBES) : - NEIGH_VAR(p, UCAST_PROBES) + NEIGH_VAR(p, APP_PROBES) + - NEIGH_VAR(p, MCAST_PROBES); + int max_probes = NEIGH_VAR(p, UCAST_PROBES) + NEIGH_VAR(p, APP_PROBES); + if (!(n->nud_state & NUD_PROBE)) + max_probes += NEIGH_VAR(p, MCAST_PROBES); + return max_probes; } static void neigh_invalidate(struct neighbour *neigh)