Files
kernel_arpi/drivers/net/mdio/fwnode_mdio.c
Yang Yingliang 543d917f69 net: mdiobus: fix unbalanced node reference count
[ Upstream commit cdde1560118f82498fc9e9a7c1ef7f0ef7755891 ]

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: bc1bee3b87 ("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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-08 11:28:41 +01:00

150 lines
3.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* fwnode helpers for the MDIO (Ethernet PHY) API
*
* This file provides helper functions for extracting PHY device information
* out of the fwnode and using it to populate an mii_bus.
*/
#include <linux/acpi.h>
#include <linux/fwnode_mdio.h>
#include <linux/of.h>
#include <linux/phy.h>
MODULE_AUTHOR("Calvin Johnson <calvin.johnson@oss.nxp.com>");
MODULE_LICENSE("GPL");
static struct mii_timestamper *
fwnode_find_mii_timestamper(struct fwnode_handle *fwnode)
{
struct of_phandle_args arg;
int err;
if (is_acpi_node(fwnode))
return NULL;
err = of_parse_phandle_with_fixed_args(to_of_node(fwnode),
"timestamper", 1, 0, &arg);
if (err == -ENOENT)
return NULL;
else if (err)
return ERR_PTR(err);
if (arg.args_count != 1)
return ERR_PTR(-EINVAL);
return register_mii_timestamper(arg.np, arg.args[0]);
}
int fwnode_mdiobus_phy_device_register(struct mii_bus *mdio,
struct phy_device *phy,
struct fwnode_handle *child, u32 addr)
{
int rc;
rc = fwnode_irq_get(child, 0);
/* Don't wait forever if the IRQ provider doesn't become available,
* just fall back to poll mode
*/
if (rc == -EPROBE_DEFER)
rc = driver_deferred_probe_check_state(&phy->mdio.dev);
if (rc == -EPROBE_DEFER)
return rc;
if (rc > 0) {
phy->irq = rc;
mdio->irq[addr] = rc;
} else {
phy->irq = mdio->irq[addr];
}
if (fwnode_property_read_bool(child, "broken-turn-around"))
mdio->phy_ignore_ta_mask |= 1 << addr;
fwnode_property_read_u32(child, "reset-assert-us",
&phy->mdio.reset_assert_delay);
fwnode_property_read_u32(child, "reset-deassert-us",
&phy->mdio.reset_deassert_delay);
/* Associate the fwnode with the device structure so it
* can be looked up later
*/
fwnode_handle_get(child);
device_set_node(&phy->mdio.dev, child);
/* All data is now stored in the phy struct;
* register it
*/
rc = phy_device_register(phy);
if (rc) {
fwnode_handle_put(child);
return rc;
}
dev_dbg(&mdio->dev, "registered phy %p fwnode at address %i\n",
child, addr);
return 0;
}
EXPORT_SYMBOL(fwnode_mdiobus_phy_device_register);
int fwnode_mdiobus_register_phy(struct mii_bus *bus,
struct fwnode_handle *child, u32 addr)
{
struct mii_timestamper *mii_ts = NULL;
struct phy_device *phy;
bool is_c45 = false;
u32 phy_id;
int rc;
mii_ts = fwnode_find_mii_timestamper(child);
if (IS_ERR(mii_ts))
return PTR_ERR(mii_ts);
rc = fwnode_property_match_string(child, "compatible",
"ethernet-phy-ieee802.3-c45");
if (rc >= 0)
is_c45 = true;
if (is_c45 || fwnode_get_phy_id(child, &phy_id))
phy = get_phy_device(bus, addr, is_c45);
else
phy = phy_device_create(bus, addr, phy_id, 0, NULL);
if (IS_ERR(phy)) {
unregister_mii_timestamper(mii_ts);
return PTR_ERR(phy);
}
if (is_acpi_node(child)) {
phy->irq = bus->irq[addr];
/* Associate the fwnode with the device structure so it
* can be looked up later.
*/
phy->mdio.dev.fwnode = fwnode_handle_get(child);
/* All data is now stored in the phy struct, so register it */
rc = phy_device_register(phy);
if (rc) {
phy_device_free(phy);
fwnode_handle_put(phy->mdio.dev.fwnode);
return rc;
}
} else if (is_of_node(child)) {
rc = fwnode_mdiobus_phy_device_register(bus, phy, child, addr);
if (rc) {
unregister_mii_timestamper(mii_ts);
phy_device_free(phy);
return rc;
}
}
/* phy->mii_ts may already be defined by the PHY driver. A
* mii_timestamper probed via the device tree will still have
* precedence.
*/
if (mii_ts)
phy->mii_ts = mii_ts;
return 0;
}
EXPORT_SYMBOL(fwnode_mdiobus_register_phy);