[PATCH 5.13 066/127] net: mdio-mux: Don't ignore memory allocation errors

Sasha Levin
2021-08-24T17:00:33Z

From: Saravana Kannan <saravanak@google.com>

[ 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>
---
drivers/net/mdio/mdio-mux.c | 28 ++++++++++++++++++----------
1 file changed, 18 insertions(+), 10 deletions(-)

diff --git a/drivers/net/mdio/mdio-mux.c b/drivers/net/mdio/mdio-mux.c
index 110e4ee85785..d6ed9033339c 100644
--- a/drivers/net/mdio/mdio-mux.c
+++ b/drivers/net/mdio/mdio-mux.c
@@ -82,6 +82,17 @@ out:

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),
@@ -144,7 +155,7 @@ 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;
@@ -152,8 +163,7 @@ 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;

@@ -182,6 +192,10 @@ 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:
@@ -193,14 +207,8 @@ 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);
--
2.30.2