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

From: Rasmus Villemoes
Date: Sat Dec 05 2020 - 13:06:18 EST


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@xxxxxxxxx>
---
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