net: mdiobus: fix unbalanced node reference count
authorYang Yingliang <yangyingliang@huawei.com>
Thu, 24 Nov 2022 15:01:30 +0000 (23:01 +0800)
committerJakub Kicinski <kuba@kernel.org>
Tue, 29 Nov 2022 02:10:25 +0000 (18:10 -0800)
commitcdde1560118f82498fc9e9a7c1ef7f0ef7755891
treed3b4523c66da10af06997496d0ab99c3f7d15165
parent7e177d32442b7ed08a9fa61b61724abc548cb248
net: mdiobus: fix unbalanced node reference count

I got the following report while doing device(mscc-miim) load test
with CONFIG_OF_UNITTEST and CONFIG_OF_DYNAMIC enabled:

  OF: ERROR: memory leak, expected refcount 1 instead of 2,
  of_node_get()/of_node_put() unbalanced - destroy cset entry:
  attach overlay node /spi/soc@0/mdio@7107009c/ethernet-phy@0

If the 'fwnode' is not an acpi node, the refcount is get in
fwnode_mdiobus_phy_device_register(), but it has never been
put when the device is freed in the normal path. So call
fwnode_handle_put() in phy_device_release() to avoid leak.

If it's an acpi node, it has never been get, but it's put
in the error path, so call fwnode_handle_get() before
phy_device_register() to keep get/put operation balanced.

Fixes: bc1bee3b87ee ("net: mdiobus: Introduce fwnode_mdiobus_register_phy()")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20221124150130.609420-1-yangyingliang@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
drivers/net/mdio/fwnode_mdio.c
drivers/net/phy/phy_device.c