From: Saravana Kannan saravanak@google.com
stable inclusion from linux-4.19.205 commit 2f87a13eb37f813aa1bfeb047052204e8ec2a325
--------------------------------
[ Upstream commit 99d81e942474cc7677d12f673f42a7ea699e2589 ]
If we are seeing memory allocation errors, don't try to continue registering child mdiobus devices. It's unlikely they'll succeed.
Fixes: 342fa1964439 ("mdio: mux: make child bus walking more permissive and errors more verbose") Signed-off-by: Saravana Kannan saravanak@google.com Reviewed-by: Andrew Lunn andrew@lunn.ch Acked-by: Marc Zyngier maz@kernel.org Tested-by: Marc Zyngier maz@kernel.org Acked-by: Kevin Hilman khilman@baylibre.com Tested-by: Kevin Hilman khilman@baylibre.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- drivers/net/phy/mdio-mux.c | 28 ++++++++++++++++++---------- 1 file changed, 18 insertions(+), 10 deletions(-)
diff --git a/drivers/net/phy/mdio-mux.c b/drivers/net/phy/mdio-mux.c index 0a86f1e4c02f5..bb7e3f12a0031 100644 --- a/drivers/net/phy/mdio-mux.c +++ b/drivers/net/phy/mdio-mux.c @@ -85,6 +85,17 @@ static int mdio_mux_write(struct mii_bus *bus, int phy_id,
static int parent_count;
+static void mdio_mux_uninit_children(struct mdio_mux_parent_bus *pb) +{ + struct mdio_mux_child_bus *cb = pb->children; + + while (cb) { + mdiobus_unregister(cb->mii_bus); + mdiobus_free(cb->mii_bus); + cb = cb->next; + } +} + int mdio_mux_init(struct device *dev, struct device_node *mux_node, int (*switch_fn)(int cur, int desired, void *data), @@ -147,7 +158,7 @@ int mdio_mux_init(struct device *dev, cb = devm_kzalloc(dev, sizeof(*cb), GFP_KERNEL); if (!cb) { ret_val = -ENOMEM; - continue; + goto err_loop; } cb->bus_number = v; cb->parent = pb; @@ -155,8 +166,7 @@ int mdio_mux_init(struct device *dev, cb->mii_bus = mdiobus_alloc(); if (!cb->mii_bus) { ret_val = -ENOMEM; - devm_kfree(dev, cb); - continue; + goto err_loop; } cb->mii_bus->priv = cb;
@@ -185,6 +195,10 @@ int mdio_mux_init(struct device *dev,
dev_err(dev, "Error: No acceptable child buses found\n"); devm_kfree(dev, pb); + +err_loop: + mdio_mux_uninit_children(pb); + of_node_put(child_bus_node); err_pb_kz: put_device(&parent_bus->dev); err_parent_bus: @@ -196,14 +210,8 @@ EXPORT_SYMBOL_GPL(mdio_mux_init); void mdio_mux_uninit(void *mux_handle) { struct mdio_mux_parent_bus *pb = mux_handle; - struct mdio_mux_child_bus *cb = pb->children; - - while (cb) { - mdiobus_unregister(cb->mii_bus); - mdiobus_free(cb->mii_bus); - cb = cb->next; - }
+ mdio_mux_uninit_children(pb); put_device(&pb->mii_bus->dev); } EXPORT_SYMBOL_GPL(mdio_mux_uninit);