Merge branch 'dsa-devres'

Vladimir Oltean says:

====================
Fix mdiobus users with devres

Commit ac3a68d5 ("net: phy: don't abuse devres in
devm_mdiobus_register()") by Bartosz Golaszewski has introduced two
classes of potential bugs by making the devres callback of
devm_mdiobus_alloc stop calling mdiobus_unregister.

The exact buggy circumstances are presented in the individual commit
messages. I have searched the tree for other occurrences, but at the
moment:

- for issue (a) I have no concrete proof that other buses except SPI and
  I2C suffer from it, and the only SPI or I2C device drivers that call
  of_mdiobus_alloc are the DSA drivers that leave a NULL
  ds->slave_mii_bus and a non-NULL ds->ops->phy_read, aka ksz9477,
  ksz8795, lan9303_i2c, vsc73xx-spi.

- for issue (b), all drivers which call of_mdiobus_alloc either use
  of_mdiobus_register too, or call mdiobus_unregister sometime within
  the ->remove path.

Although at this point I've seen enough strangeness caused by this
"device_del during ->shutdown" that I'm just going to copy the SPI and
I2C subsystem maintainers to this patch series, to get their feedback
whether they've had reports about things like this before. I don't think
other buses behave in this way, it forces SPI and I2C devices to have to
protect themselves from a really strange set of issues.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>