This is a note to let you know that I've just added the patch titled ravb: Fixed to be able to unload modules 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: ravb-fixed-to-be-able-to-unload-modules.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 0995dcfb52720a3df87aae91f914947f3e57605f Author: Yuusuke Ashizuka <ashiduka@xxxxxxxxxxx> Date: Thu Aug 20 18:43:07 2020 +0900 ravb: Fixed to be able to unload modules [ Upstream commit 1838d6c62f57836639bd3d83e7855e0ee4f6defc ] When this driver is built as a module, I cannot rmmod it after insmoding it. This is because that this driver calls ravb_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 ravb 40960 1 $ rmmod ravb rmmod: ERROR: Module ravb is in use Call ravb_mdio_init() at open and free_mdio_bitbang() at close, thereby rmmod is possible in the ifdown state. Fixes: c156633f1353 ("Renesas Ethernet AVB driver proper") Signed-off-by: Yuusuke Ashizuka <ashiduka@xxxxxxxxxxx> Reviewed-by: Sergei Shtylyov <sergei.shtylyov@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index 30cdabf64ccc1..907ae1359a7c1 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -1336,6 +1336,51 @@ 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; +} + /* Network device open function for Ethernet AVB */ static int ravb_open(struct net_device *ndev) { @@ -1344,6 +1389,13 @@ static int ravb_open(struct net_device *ndev) struct device *dev = &pdev->dev; int error; + /* MDIO bus init */ + error = ravb_mdio_init(priv); + if (error) { + netdev_err(ndev, "failed to initialize MDIO\n"); + return error; + } + napi_enable(&priv->napi[RAVB_BE]); napi_enable(&priv->napi[RAVB_NC]); @@ -1421,6 +1473,7 @@ out_free_irq: out_napi_off: napi_disable(&priv->napi[RAVB_NC]); napi_disable(&priv->napi[RAVB_BE]); + ravb_mdio_release(priv); return error; } @@ -1730,6 +1783,8 @@ static int ravb_close(struct net_device *ndev) ravb_ring_free(ndev, RAVB_BE); ravb_ring_free(ndev, RAVB_NC); + ravb_mdio_release(priv); + return 0; } @@ -1881,51 +1936,6 @@ 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; -} - static const struct of_device_id ravb_match_table[] = { { .compatible = "renesas,etheravb-r8a7790", .data = (void *)RCAR_GEN2 }, { .compatible = "renesas,etheravb-r8a7794", .data = (void *)RCAR_GEN2 }, @@ -2166,13 +2176,6 @@ static int ravb_probe(struct platform_device *pdev) eth_hw_addr_random(ndev); } - /* MDIO bus init */ - error = ravb_mdio_init(priv); - if (error) { - dev_err(&pdev->dev, "failed to initialize MDIO\n"); - goto out_dma_free; - } - netif_napi_add(ndev, &priv->napi[RAVB_BE], ravb_poll, 64); netif_napi_add(ndev, &priv->napi[RAVB_NC], ravb_poll, 64); @@ -2194,8 +2197,6 @@ static int ravb_probe(struct platform_device *pdev) out_napi_del: netif_napi_del(&priv->napi[RAVB_NC]); netif_napi_del(&priv->napi[RAVB_BE]); - ravb_mdio_release(priv); -out_dma_free: dma_free_coherent(ndev->dev.parent, priv->desc_bat_size, priv->desc_bat, priv->desc_bat_dma); @@ -2227,7 +2228,6 @@ static int ravb_remove(struct platform_device *pdev) unregister_netdev(ndev); netif_napi_del(&priv->napi[RAVB_NC]); netif_napi_del(&priv->napi[RAVB_BE]); - ravb_mdio_release(priv); pm_runtime_disable(&pdev->dev); free_netdev(ndev); platform_set_drvdata(pdev, NULL);