[PATCH net-next] net: dsa: print the MTU value that could not be set

[PATCH net-next] net: dsa: print the MTU value that could not be set

[Rasmus Villemoes]

These warnings become somewhat more informative when they include the
MTU value that could not be set and not just the errno.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
---
 net/dsa/master.c | 7 ++++---
 net/dsa/slave.c  | 4 ++--
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/net/dsa/master.c b/net/dsa/master.c
index c91de041a91d..5a0f6fec4271 100644
--- a/net/dsa/master.c
+++ b/net/dsa/master.c
@@ -308,14 +308,15 @@ static struct lock_class_key dsa_master_addr_list_lock_key;
 
 int dsa_master_setup(struct net_device *dev, struct dsa_port *cpu_dp)
 {
+	int mtu = ETH_DATA_LEN + cpu_dp->tag_ops->overhead;
 	int ret;
 
 	rtnl_lock();
-	ret = dev_set_mtu(dev, ETH_DATA_LEN + cpu_dp->tag_ops->overhead);
+	ret = dev_set_mtu(dev, mtu);
 	rtnl_unlock();
 	if (ret)
-		netdev_warn(dev, "error %d setting MTU to include DSA overhead\n",
-			    ret);
+		netdev_warn(dev, "error %d setting MTU to %d to include DSA overhead\n",
+			    ret, mtu);
 
 	/* If we use a tagging format that doesn't have an ethertype
 	 * field, make sure that all packets from this point on get
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 3bc5ca40c9fb..b4a813b8a828 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -1820,8 +1820,8 @@ int dsa_slave_create(struct dsa_port *port)
 	ret = dsa_slave_change_mtu(slave_dev, ETH_DATA_LEN);
 	rtnl_unlock();
 	if (ret && ret != -EOPNOTSUPP)
-		dev_warn(ds->dev, "nonfatal error %d setting MTU on port %d\n",
-			 ret, port->index);
+		dev_warn(ds->dev, "nonfatal error %d setting MTU to %d on port %d\n",
+			 ret, ETH_DATA_LEN, port->index);
 
 	netif_carrier_off(slave_dev);
 
-- 
2.23.0

Re: [PATCH net-next] net: dsa: print the MTU value that could not be set

[Jakub Kicinski]

On Sat,  5 Dec 2020 14:39:44 +0100 Rasmus Villemoes wrote:
> These warnings become somewhat more informative when they include the
> MTU value that could not be set and not just the errno.
> 
> Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>

Applied, thanks!