There has been some controversy related to the sanity check that a CPU
port exists, and commit e8b1d76980 ("net: dsa: felix: Fix memory leak
in felix_setup_mmio_filtering") even "corrected" an apparent memory leak
as static analysis tools see it.
However, the check is completely dead code, since the earliest point at
which felix_setup_mmio_filtering() can be called is:
felix_pci_probe
-> dsa_register_switch
-> dsa_switch_probe
-> dsa_tree_setup
-> dsa_tree_setup_cpu_ports
-> dsa_tree_setup_default_cpu
-> contains the "DSA: tree %d has no CPU port\n" check
-> dsa_tree_setup_master
-> dsa_master_setup
-> sysfs_create_group(&dev->dev.kobj, &dsa_group);
-> makes tagging_store() callable
-> dsa_tree_change_tag_proto
-> dsa_tree_notify
-> dsa_switch_event
-> dsa_switch_change_tag_proto
-> ds->ops->change_tag_protocol
-> felix_change_tag_protocol
-> felix_set_tag_protocol
-> felix_setup_tag_8021q
-> felix_setup_mmio_filtering
-> breaks at first CPU port
So probing would have failed earlier if there wasn't any CPU port
defined.
To avoid all confusion, delete the dead code and replace it with a
comment.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
d78637a8a0