From a827d6c0c3b58f063c3581f6eb44e93f3175f180 Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Tue, 11 Jun 2019 10:19:41 +0300 Subject: [PATCH] mlxsw: spectrum_router: Refresh nexthop neighbour when it becomes dead [ Upstream commit 83d5782681cc12b3d485a83cb34c46b2445f510c ] The driver tries to periodically refresh neighbours that are used to reach nexthops. This is done by periodically calling neigh_event_send(). However, if the neighbour becomes dead, there is nothing we can do to return it to a connected state and the above function call is basically a NOP. This results in the nexthop never being written to the device's adjacency table and therefore never used to forward packets. Fix this by dropping our reference from the dead neighbour and associating the nexthop with a new neigbhour which we will try to refresh. Fixes: a7ff87acd995 ("mlxsw: spectrum_router: Implement next-hop routing") Signed-off-by: Ido Schimmel Reported-by: Alex Veber Tested-by: Alex Veber Acked-by: Jiri Pirko Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- .../ethernet/mellanox/mlxsw/spectrum_router.c | 73 ++++++++++++++++++- 1 file changed, 70 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c index 44b6c2ac5961..76960d3adfc0 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c @@ -2228,7 +2228,7 @@ static void mlxsw_sp_router_probe_unresolved_nexthops(struct work_struct *work) static void mlxsw_sp_nexthop_neigh_update(struct mlxsw_sp *mlxsw_sp, struct mlxsw_sp_neigh_entry *neigh_entry, - bool removing); + bool removing, bool dead); static enum mlxsw_reg_rauht_op mlxsw_sp_rauht_op(bool adding) { @@ -2359,7 +2359,8 @@ static void mlxsw_sp_router_neigh_event_work(struct work_struct *work) memcpy(neigh_entry->ha, ha, ETH_ALEN); mlxsw_sp_neigh_entry_update(mlxsw_sp, neigh_entry, entry_connected); - mlxsw_sp_nexthop_neigh_update(mlxsw_sp, neigh_entry, !entry_connected); + mlxsw_sp_nexthop_neigh_update(mlxsw_sp, neigh_entry, !entry_connected, + dead); if (!neigh_entry->connected && list_empty(&neigh_entry->nexthop_list)) mlxsw_sp_neigh_entry_destroy(mlxsw_sp, neigh_entry); @@ -3323,13 +3324,79 @@ static void __mlxsw_sp_nexthop_neigh_update(struct mlxsw_sp_nexthop *nh, nh->update = 1; } +static int +mlxsw_sp_nexthop_dead_neigh_replace(struct mlxsw_sp *mlxsw_sp, + struct mlxsw_sp_neigh_entry *neigh_entry) +{ + struct neighbour *n, *old_n = neigh_entry->key.n; + struct mlxsw_sp_nexthop *nh; + bool entry_connected; + u8 nud_state, dead; + int err; + + nh = list_first_entry(&neigh_entry->nexthop_list, + struct mlxsw_sp_nexthop, neigh_list_node); + + n = neigh_lookup(nh->nh_grp->neigh_tbl, &nh->gw_addr, nh->rif->dev); + if (!n) { + n = neigh_create(nh->nh_grp->neigh_tbl, &nh->gw_addr, + nh->rif->dev); + if (IS_ERR(n)) + return PTR_ERR(n); + neigh_event_send(n, NULL); + } + + mlxsw_sp_neigh_entry_remove(mlxsw_sp, neigh_entry); + neigh_entry->key.n = n; + err = mlxsw_sp_neigh_entry_insert(mlxsw_sp, neigh_entry); + if (err) + goto err_neigh_entry_insert; + + read_lock_bh(&n->lock); + nud_state = n->nud_state; + dead = n->dead; + read_unlock_bh(&n->lock); + entry_connected = nud_state & NUD_VALID && !dead; + + list_for_each_entry(nh, &neigh_entry->nexthop_list, + neigh_list_node) { + neigh_release(old_n); + neigh_clone(n); + __mlxsw_sp_nexthop_neigh_update(nh, !entry_connected); + mlxsw_sp_nexthop_group_refresh(mlxsw_sp, nh->nh_grp); + } + + neigh_release(n); + + return 0; + +err_neigh_entry_insert: + neigh_entry->key.n = old_n; + mlxsw_sp_neigh_entry_insert(mlxsw_sp, neigh_entry); + neigh_release(n); + return err; +} + static void mlxsw_sp_nexthop_neigh_update(struct mlxsw_sp *mlxsw_sp, struct mlxsw_sp_neigh_entry *neigh_entry, - bool removing) + bool removing, bool dead) { struct mlxsw_sp_nexthop *nh; + if (list_empty(&neigh_entry->nexthop_list)) + return; + + if (dead) { + int err; + + err = mlxsw_sp_nexthop_dead_neigh_replace(mlxsw_sp, + neigh_entry); + if (err) + dev_err(mlxsw_sp->bus_info->dev, "Failed to replace dead neigh\n"); + return; + } + list_for_each_entry(nh, &neigh_entry->nexthop_list, neigh_list_node) { __mlxsw_sp_nexthop_neigh_update(nh, removing); -- GitLab