Thread (13 messages) 13 messages, 4 authors, 2020-08-06

Re: [PATCH v2] ravb: Fixed the problem that rmmod can not be done

From: Sergei Shtylyov <hidden>
Date: 2020-07-31 18:32:37
Also in: linux-renesas-soc

On 7/30/20 1:01 PM, Yuusuke Ashizuka wrote:

   CCing DaveM (as you should have done from the start)...
ravb is a module driver, but I cannot rmmod it after insmod it.
ravb does mdio_init() at the time of probe, and module->refcnt is incremented
by alloc_mdio_bitbang() called after that.
Therefore, even if ifup is not performed, the driver is in use and rmmod cannot
be performed.

$ lsmod
Module                  Size  Used by
   Did you also build mdio-bitbang.c as a module? For the in-kernal driver, not
being able to rmmod the 'ravb' one sounds logical. :-)
ravb                   40960  1
$ rmmod ravb
rmmod: ERROR: Module ravb is in use

Fixed to execute mdio_init() at open and free_mdio() at close, thereby rmmod is
    Call ravb_mdio_init() at open and free_mdio_bitbang() at close.
possible in the ifdown state.
Fixes: c156633f1353 ("Renesas Ethernet AVB driver proper")
Signed-off-by: Yuusuke Ashizuka <redacted>
Reviewed-by: Sergei Shtylyov <redacted>

[...]
quoted hunk ↗ jump to hunk
diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index 99f7aae102ce..df89d09b253e 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -1342,6 +1342,51 @@ static inline int ravb_hook_irq(unsigned int irq, irq_handler_t handler,
 	return error;
 }
 
+/* MDIO bus init function */
+static int ravb_mdio_init(struct ravb_private *priv)
+{
+	struct platform_device *pdev = priv->pdev;
+	struct device *dev = &pdev->dev;
+	int error;
+
+	/* Bitbang init */
+	priv->mdiobb.ops = &bb_ops;
+
+	/* MII controller setting */
+	priv->mii_bus = alloc_mdio_bitbang(&priv->mdiobb);
+	if (!priv->mii_bus)
+		return -ENOMEM;
+
+	/* Hook up MII support for ethtool */
+	priv->mii_bus->name = "ravb_mii";
+	priv->mii_bus->parent = dev;
+	snprintf(priv->mii_bus->id, MII_BUS_ID_SIZE, "%s-%x",
+		 pdev->name, pdev->id);
+
+	/* Register MDIO bus */
+	error = of_mdiobus_register(priv->mii_bus, dev->of_node);
+	if (error)
+		goto out_free_bus;
+
+	return 0;
+
+out_free_bus:
+	free_mdio_bitbang(priv->mii_bus);
+	return error;
+}
+
+/* MDIO bus release function */
+static int ravb_mdio_release(struct ravb_private *priv)
+{
+	/* Unregister mdio bus */
+	mdiobus_unregister(priv->mii_bus);
+
+	/* Free bitbang info */
+	free_mdio_bitbang(priv->mii_bus);
+
+	return 0;
+}
+
[...]
quoted hunk ↗ jump to hunk
@@ -1887,51 +1942,6 @@ static const struct net_device_ops ravb_netdev_ops = {
 	.ndo_set_features	= ravb_set_features,
 };
 
-/* MDIO bus init function */
-static int ravb_mdio_init(struct ravb_private *priv)
-{
-	struct platform_device *pdev = priv->pdev;
-	struct device *dev = &pdev->dev;
-	int error;
-
-	/* Bitbang init */
-	priv->mdiobb.ops = &bb_ops;
-
-	/* MII controller setting */
-	priv->mii_bus = alloc_mdio_bitbang(&priv->mdiobb);
-	if (!priv->mii_bus)
-		return -ENOMEM;
-
-	/* Hook up MII support for ethtool */
-	priv->mii_bus->name = "ravb_mii";
-	priv->mii_bus->parent = dev;
-	snprintf(priv->mii_bus->id, MII_BUS_ID_SIZE, "%s-%x",
-		 pdev->name, pdev->id);
-
-	/* Register MDIO bus */
-	error = of_mdiobus_register(priv->mii_bus, dev->of_node);
-	if (error)
-		goto out_free_bus;
-
-	return 0;
-
-out_free_bus:
-	free_mdio_bitbang(priv->mii_bus);
-	return error;
-}
-
-/* MDIO bus release function */
-static int ravb_mdio_release(struct ravb_private *priv)
-{
-	/* Unregister mdio bus */
-	mdiobus_unregister(priv->mii_bus);
-
-	/* Free bitbang info */
-	free_mdio_bitbang(priv->mii_bus);
-
-	return 0;
-}
-
   Dave, would you tolerate the forward declarations here instead (to avoid the function moves, to be later
done in the net-next tree)?

[...]

MBR, Sergei
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help