This is a note to let you know that I've just added the patch titled net: mdio: introduce a shutdown method to mdio device drivers to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-mdio-introduce-a-shutdown-method-to-mdio-device-.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit de3b3abae577549b78c17024b700b02f2341b905 Author: Vladimir Oltean <vladimir.oltean@xxxxxxx> Date: Fri Sep 17 16:34:32 2021 +0300 net: mdio: introduce a shutdown method to mdio device drivers [ Upstream commit cf9579976f724ad517cc15b7caadea728c7e245c ] MDIO-attached devices might have interrupts and other things that might need quiesced when we kexec into a new kernel. Things are even more creepy when those interrupt lines are shared, and in that case it is absolutely mandatory to disable all interrupt sources. Moreover, MDIO devices might be DSA switches, and DSA needs its own shutdown method to unlink from the DSA master, which is a new requirement that appeared after commit 2f1e8ea726e9 ("net: dsa: link interfaces with the DSA master to get rid of lockdep warnings"). So introduce a ->shutdown method in the MDIO device driver structure. Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx> Reviewed-by: Andrew Lunn <andrew@xxxxxxx> Reviewed-by: Florian Fainelli <f.fainelli@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/phy/mdio_device.c b/drivers/net/phy/mdio_device.c index c1d345c3cab3..b2dd293fc87e 100644 --- a/drivers/net/phy/mdio_device.c +++ b/drivers/net/phy/mdio_device.c @@ -180,6 +180,16 @@ static int mdio_remove(struct device *dev) return 0; } +static void mdio_shutdown(struct device *dev) +{ + struct mdio_device *mdiodev = to_mdio_device(dev); + struct device_driver *drv = mdiodev->dev.driver; + struct mdio_driver *mdiodrv = to_mdio_driver(drv); + + if (mdiodrv->shutdown) + mdiodrv->shutdown(mdiodev); +} + /** * mdio_driver_register - register an mdio_driver with the MDIO layer * @new_driver: new mdio_driver to register @@ -194,6 +204,7 @@ int mdio_driver_register(struct mdio_driver *drv) mdiodrv->driver.bus = &mdio_bus_type; mdiodrv->driver.probe = mdio_probe; mdiodrv->driver.remove = mdio_remove; + mdiodrv->driver.shutdown = mdio_shutdown; retval = driver_register(&mdiodrv->driver); if (retval) { diff --git a/include/linux/mdio.h b/include/linux/mdio.h index a7604248777b..0f1f784de80e 100644 --- a/include/linux/mdio.h +++ b/include/linux/mdio.h @@ -64,6 +64,9 @@ struct mdio_driver { /* Clears up any memory if needed */ void (*remove)(struct mdio_device *mdiodev); + + /* Quiesces the device on system shutdown, turns off interrupts etc */ + void (*shutdown)(struct mdio_device *mdiodev); }; #define to_mdio_driver(d) \ container_of(to_mdio_common_driver(d), struct mdio_driver, mdiodrv)