diff options
Diffstat (limited to 'pkgs/patches-linux-5.15/765-3-net-next-net-dsa-stop-updating-master-MTU-from-master.c.patch')
| -rw-r--r-- | pkgs/patches-linux-5.15/765-3-net-next-net-dsa-stop-updating-master-MTU-from-master.c.patch | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/pkgs/patches-linux-5.15/765-3-net-next-net-dsa-stop-updating-master-MTU-from-master.c.patch b/pkgs/patches-linux-5.15/765-3-net-next-net-dsa-stop-updating-master-MTU-from-master.c.patch new file mode 100644 index 0000000..d1126de --- /dev/null +++ b/pkgs/patches-linux-5.15/765-3-net-next-net-dsa-stop-updating-master-MTU-from-master.c.patch @@ -0,0 +1,91 @@ +From a1ff94c2973c43bc1e2677ac63ebb15b1d1ff846 Mon Sep 17 00:00:00 2001 +From: Vladimir Oltean <vladimir.oltean@nxp.com> +Date: Thu, 6 Jan 2022 01:11:14 +0200 +Subject: [PATCH 3/6] net: dsa: stop updating master MTU from master.c + +At present there are two paths for changing the MTU of the DSA master. + +The first is: + +dsa_tree_setup +-> dsa_tree_setup_ports + -> dsa_port_setup + -> dsa_slave_create + -> dsa_slave_change_mtu + -> dev_set_mtu(master) + +The second is: + +dsa_tree_setup +-> dsa_tree_setup_master + -> dsa_master_setup + -> dev_set_mtu(dev) + +So the dev_set_mtu() call from dsa_master_setup() has been effectively +superseded by the dsa_slave_change_mtu(slave_dev, ETH_DATA_LEN) that is +done from dsa_slave_create() for each user port. The later function also +updates the master MTU according to the largest user port MTU from the +tree. Therefore, updating the master MTU through a separate code path +isn't needed. + +Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> +Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + net/dsa/master.c | 25 +------------------------ + 1 file changed, 1 insertion(+), 24 deletions(-) + +--- a/net/dsa/master.c ++++ b/net/dsa/master.c +@@ -330,28 +330,13 @@ static const struct attribute_group dsa_ + .attrs = dsa_slave_attrs, + }; + +-static void dsa_master_reset_mtu(struct net_device *dev) +-{ +- int err; +- +- rtnl_lock(); +- err = dev_set_mtu(dev, ETH_DATA_LEN); +- if (err) +- netdev_dbg(dev, +- "Unable to reset MTU to exclude DSA overheads\n"); +- rtnl_unlock(); +-} +- + static struct lock_class_key dsa_master_addr_list_lock_key; + + int dsa_master_setup(struct net_device *dev, struct dsa_port *cpu_dp) + { +- const struct dsa_device_ops *tag_ops = cpu_dp->tag_ops; + struct dsa_switch *ds = cpu_dp->ds; + struct device_link *consumer_link; +- int mtu, ret; +- +- mtu = ETH_DATA_LEN + dsa_tag_protocol_overhead(tag_ops); ++ int ret; + + /* The DSA master must use SET_NETDEV_DEV for this to work. */ + consumer_link = device_link_add(ds->dev, dev->dev.parent, +@@ -361,13 +346,6 @@ int dsa_master_setup(struct net_device * + "Failed to create a device link to DSA switch %s\n", + dev_name(ds->dev)); + +- rtnl_lock(); +- ret = dev_set_mtu(dev, mtu); +- rtnl_unlock(); +- if (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 + * sent to the tag format's receive function. +@@ -405,7 +383,6 @@ void dsa_master_teardown(struct net_devi + sysfs_remove_group(&dev->dev.kobj, &dsa_group); + dsa_netdev_ops_set(dev, NULL); + dsa_master_ethtool_teardown(dev); +- dsa_master_reset_mtu(dev); + dsa_master_set_promiscuity(dev, -1); + + dev->dsa_ptr = NULL; |