[PATCH 5.0 041/122] ixgbe: fix mdio bus registration

Greg Kroah-Hartman
2019-05-06T14:35:15Z

[ Upstream commit 7ec52b9df7d7472240fa96223185894b1897aeb0 ]

The ixgbe ignores errors returned from mdiobus_register() and leaves
adapter->mii_bus non-NULL and MDIO bus state as MDIOBUS_ALLOCATED.
This triggers a BUG from mdiobus_unregister() during ixgbe_remove() call.

Fixes: 8fa10ef01260 ("ixgbe: register a mdiobus")
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Sasha Levin (Microsoft) <sashal@kernel.org>
---
drivers/net/ethernet/intel/ixgbe/ixgbe_phy.c | 16 +++++++++-------
1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_phy.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_phy.c
index cc4907f9ff02..2fb97967961c 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_phy.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_phy.c
@@ -905,13 +905,12 @@ s32 ixgbe_mii_bus_init(struct ixgbe_hw *hw)
struct pci_dev *pdev = adapter->pdev;
struct device *dev = &adapter->netdev->dev;
struct mii_bus *bus;
+ int err = -ENODEV;

- adapter->mii_bus = devm_mdiobus_alloc(dev);
- if (!adapter->mii_bus)
+ bus = devm_mdiobus_alloc(dev);
+ if (!bus)
return -ENOMEM;

- bus = adapter->mii_bus;
-
switch (hw->device_id) {
/* C3000 SoCs */
case IXGBE_DEV_ID_X550EM_A_KR:
@@ -949,12 +948,15 @@ s32 ixgbe_mii_bus_init(struct ixgbe_hw *hw)
*/
hw->phy.mdio.mode_support = MDIO_SUPPORTS_C45 | MDIO_SUPPORTS_C22;

- return mdiobus_register(bus);
+ err = mdiobus_register(bus);
+ if (!err) {
+ adapter->mii_bus = bus;
+ return 0;
+ }

ixgbe_no_mii_bus:
devm_mdiobus_free(dev, bus);
- adapter->mii_bus = NULL;
- return -ENODEV;
+ return err;
}

/**
--
2.20.1