[PATCH net] nfp: flower: avoid taking mutex in atomic context

[Simon Horman <simon.horman@corigine.com>]

From: Yanguo Li <yanguo.li@corigine.com>

A mutex may sleep, which is not permitted in atomic context.
Avoid a case where this may arise by moving the to
nfp_flower_lag_get_info_from_netdev() in nfp_tun_write_neigh() spinlock.

Fixes: abc210952af7 ("nfp: flower: tunnel neigh support bond offload")
Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Yanguo Li <yanguo.li@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
---
 drivers/net/ethernet/netronome/nfp/flower/tunnel_conf.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/netronome/nfp/flower/tunnel_conf.c b/drivers/net/ethernet/netronome/nfp/flower/tunnel_conf.c
index a8678d5612ee..060a77f2265d 100644
--- a/drivers/net/ethernet/netronome/nfp/flower/tunnel_conf.c
+++ b/drivers/net/ethernet/netronome/nfp/flower/tunnel_conf.c
@@ -460,6 +460,7 @@ nfp_tun_write_neigh(struct net_device *netdev, struct nfp_app *app,
 			    sizeof(struct nfp_tun_neigh_v4);
 	unsigned long cookie = (unsigned long)neigh;
 	struct nfp_flower_priv *priv = app->priv;
+	struct nfp_tun_neigh_lag lag_info;
 	struct nfp_neigh_entry *nn_entry;
 	u32 port_id;
 	u8 mtype;
@@ -468,6 +469,11 @@ nfp_tun_write_neigh(struct net_device *netdev, struct nfp_app *app,
 	if (!port_id)
 		return;
 
+	if ((port_id & NFP_FL_LAG_OUT) == NFP_FL_LAG_OUT) {
+		memset(&lag_info, 0, sizeof(struct nfp_tun_neigh_lag));
+		nfp_flower_lag_get_info_from_netdev(app, netdev, &lag_info);
+	}
+
 	spin_lock_bh(&priv->predt_lock);
 	nn_entry = rhashtable_lookup_fast(&priv->neigh_table, &cookie,
 					  neigh_table_params);
@@ -515,7 +521,7 @@ nfp_tun_write_neigh(struct net_device *netdev, struct nfp_app *app,
 		neigh_ha_snapshot(common->dst_addr, neigh, netdev);
 
 		if ((port_id & NFP_FL_LAG_OUT) == NFP_FL_LAG_OUT)
-			nfp_flower_lag_get_info_from_netdev(app, netdev, lag);
+			memcpy(lag, &lag_info, sizeof(struct nfp_tun_neigh_lag));
 		common->port_id = cpu_to_be32(port_id);
 
 		if (rhashtable_insert_fast(&priv->neigh_table,
-- 
2.30.2