From 7a576dfd9ed4fd0f32bb838ce4f644af201ac7df Mon Sep 17 00:00:00 2001 From: Faisal Latif Date: Wed, 9 Dec 2009 15:54:33 -0800 Subject: [PATCH] RDMA/nes: Fix stale ARP issue When the remote node's ethernet address changes, the connection keeps trying to connect using the old address. The connection wil continue failing until the driver is unloaded and loaded again (eiter reboot or rmmod). Fix this by checking that the NIC has the correct address before starting a connection. Signed-off-by: Faisal Latif Signed-off-by: Roland Dreier --- drivers/infiniband/hw/nes/nes_cm.c | 37 ++++++++++++++++++++++-------- 1 file changed, 27 insertions(+), 10 deletions(-) diff --git a/drivers/infiniband/hw/nes/nes_cm.c b/drivers/infiniband/hw/nes/nes_cm.c index 4acf04a03e1..39468c27703 100644 --- a/drivers/infiniband/hw/nes/nes_cm.c +++ b/drivers/infiniband/hw/nes/nes_cm.c @@ -1098,12 +1098,13 @@ static inline int mini_cm_accelerated(struct nes_cm_core *cm_core, /** * nes_addr_resolve_neigh */ -static int nes_addr_resolve_neigh(struct nes_vnic *nesvnic, u32 dst_ip) +static int nes_addr_resolve_neigh(struct nes_vnic *nesvnic, u32 dst_ip, int arpindex) { struct rtable *rt; struct flowi fl; struct neighbour *neigh; - int rc = -1; + int rc = arpindex; + struct nes_adapter *nesadapter = nesvnic->nesdev->nesadapter; memset(&fl, 0, sizeof fl); fl.nl_u.ip4_u.daddr = htonl(dst_ip); @@ -1119,6 +1120,21 @@ static int nes_addr_resolve_neigh(struct nes_vnic *nesvnic, u32 dst_ip) nes_debug(NES_DBG_CM, "Neighbor MAC address for 0x%08X" " is %pM, Gateway is 0x%08X \n", dst_ip, neigh->ha, ntohl(rt->rt_gateway)); + + if (arpindex >= 0) { + if (!memcmp(nesadapter->arp_table[arpindex].mac_addr, + neigh->ha, ETH_ALEN)){ + /* Mac address same as in nes_arp_table */ + neigh_release(neigh); + ip_rt_put(rt); + return rc; + } + + nes_manage_arp_cache(nesvnic->netdev, + nesadapter->arp_table[arpindex].mac_addr, + dst_ip, NES_ARP_DELETE); + } + nes_manage_arp_cache(nesvnic->netdev, neigh->ha, dst_ip, NES_ARP_ADD); rc = nes_arp_table(nesvnic->nesdev, dst_ip, NULL, @@ -1134,7 +1150,6 @@ static int nes_addr_resolve_neigh(struct nes_vnic *nesvnic, u32 dst_ip) return rc; } - /** * make_cm_node - create a new instance of a cm node */ @@ -1144,6 +1159,7 @@ static struct nes_cm_node *make_cm_node(struct nes_cm_core *cm_core, { struct nes_cm_node *cm_node; struct timespec ts; + int oldarpindex = 0; int arpindex = 0; struct nes_device *nesdev; struct nes_adapter *nesadapter; @@ -1197,17 +1213,18 @@ static struct nes_cm_node *make_cm_node(struct nes_cm_core *cm_core, nesadapter = nesdev->nesadapter; cm_node->loopbackpartner = NULL; + /* get the mac addr for the remote node */ if (ipv4_is_loopback(htonl(cm_node->rem_addr))) arpindex = nes_arp_table(nesdev, ntohl(nesvnic->local_ipaddr), NULL, NES_ARP_RESOLVE); - else - arpindex = nes_arp_table(nesdev, cm_node->rem_addr, NULL, NES_ARP_RESOLVE); + else { + oldarpindex = nes_arp_table(nesdev, cm_node->rem_addr, NULL, NES_ARP_RESOLVE); + arpindex = nes_addr_resolve_neigh(nesvnic, cm_info->rem_addr, oldarpindex); + + } if (arpindex < 0) { - arpindex = nes_addr_resolve_neigh(nesvnic, cm_info->rem_addr); - if (arpindex < 0) { - kfree(cm_node); - return NULL; - } + kfree(cm_node); + return NULL; } /* copy the mac addr to node context */