This is a note to let you know that I've just added the patch titled
net: mdio-mux: fix unbalanced put_device
to the 4.9-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-mux-fix-unbalanced-put_device.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 60f786525032432af1b7d9b8935cb12936244ccd Mon Sep 17 00:00:00 2001
From: Corentin Labbe <clabbe.montjoie@xxxxxxxxx>
Date: Fri, 1 Sep 2017 13:56:04 +0200
Subject: net: mdio-mux: fix unbalanced put_device
From: Corentin Labbe <clabbe.montjoie@xxxxxxxxx>
commit 60f786525032432af1b7d9b8935cb12936244ccd upstream.
mdio_mux_uninit() call put_device (unconditionally) because of
of_mdio_find_bus() in mdio_mux_init.
But of_mdio_find_bus is only called if mux_bus is empty.
If mux_bus is set, mdio_mux_uninit will print a "refcount_t: underflow"
trace.
This patch add a get_device in the other branch of "if (mux_bus)".
Signed-off-by: Corentin Labbe <clabbe.montjoie@xxxxxxxxx>
Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/phy/mdio-mux.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
--- a/drivers/net/phy/mdio-mux.c
+++ b/drivers/net/phy/mdio-mux.c
@@ -117,6 +117,7 @@ int mdio_mux_init(struct device *dev,
} else {
parent_bus_node = NULL;
parent_bus = mux_bus;
+ get_device(&parent_bus->dev);
}
pb = devm_kzalloc(dev, sizeof(*pb), GFP_KERNEL);
@@ -182,9 +183,7 @@ int mdio_mux_init(struct device *dev,
devm_kfree(dev, pb);
err_pb_kz:
- /* balance the reference of_mdio_find_bus() took */
- if (!mux_bus)
- put_device(&parent_bus->dev);
+ put_device(&parent_bus->dev);
err_parent_bus:
of_node_put(parent_bus_node);
return ret_val;
@@ -202,7 +201,6 @@ void mdio_mux_uninit(void *mux_handle)
cb = cb->next;
}
- /* balance the reference of_mdio_find_bus() in mdio_mux_init() took */
put_device(&pb->mii_bus->dev);
}
EXPORT_SYMBOL_GPL(mdio_mux_uninit);
Patches currently in stable-queue which might be from clabbe.montjoie@xxxxxxxxx are
queue-4.9/net-mdio-mux-fix-unbalanced-put_device.patch
