| Message ID | 1471610891-13353-2-git-send-email-appanad@xilinx.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Aug 19, 2016 at 06:18:11PM +0530, Kedareswara rao Appana wrote: > This patch fixes the below race conditions in the driver. > ---> Fix Opps after unload the driver as a module > ---> Use spin locks where relevant. > ---> Take reference on the external phy to prevent issues > when phy driver is unloaded. Each one of these should be an individual patch. > > Reported-by: Andrew Lunn <andrew@lunn.ch> > Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com> > --- > drivers/net/phy/xilinx_gmii2rgmii.c | 32 +++++++++++++++++++++++++++++++- > 1 file changed, 31 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/phy/xilinx_gmii2rgmii.c b/drivers/net/phy/xilinx_gmii2rgmii.c > index 7336fd0..cdd9d95 100644 > --- a/drivers/net/phy/xilinx_gmii2rgmii.c > +++ b/drivers/net/phy/xilinx_gmii2rgmii.c > @@ -34,6 +34,7 @@ struct gmii2rgmii { > struct phy_driver *phy_drv; > struct phy_driver conv_phy_drv; > int addr; > + spinlock_t phy_lock; The phy already have a lock. > }; > > static int xgmiitorgmii_read_status(struct phy_device *phydev) > @@ -55,7 +56,7 @@ static int xgmiitorgmii_read_status(struct phy_device *phydev) > val |= BMCR_SPEED1000; > else if (phydev->speed == SPEED_100) > val |= BMCR_SPEED100; > - else > + else if (phydev->speed == SPEED_10) > val |= BMCR_SPEED10; I said you want to return an error is the PHY is using a speed your converter cannot support. I don't see an error being raised here. > err = mdiobus_write(phydev->mdio.bus, priv->addr, XILINX_GMII2RGMII_REG, > @@ -71,6 +72,8 @@ int xgmiitorgmii_probe(struct mdio_device *mdiodev) > struct device *dev = &mdiodev->dev; > struct device_node *np = dev->of_node, *phy_node; > struct gmii2rgmii *priv; > + struct mii_bus *bus; > + unsigned long flags; > > priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); > if (!priv) > @@ -88,17 +91,43 @@ int xgmiitorgmii_probe(struct mdio_device *mdiodev) > return -EPROBE_DEFER; > } > > + spin_lock_init(&priv->phy_lock); > + > + bus = priv->phy_dev->mdio.bus; > + if (!try_module_get(bus->owner)) { > + dev_err(dev, "failed to get the bus module\n"); > + return -EIO; > + } The comment at the top says you are taking a reference to the phy. Here you take a reference to the mdio bus driver??? > + > + get_device(&priv->phy_dev->mdio.dev); > + > priv->addr = mdiodev->addr; > priv->phy_drv = priv->phy_dev->drv; > memcpy(&priv->conv_phy_drv, priv->phy_dev->drv, > sizeof(struct phy_driver)); > priv->conv_phy_drv.read_status = xgmiitorgmii_read_status; > priv->phy_dev->priv = priv; > + spin_lock_irqsave(&priv->phy_lock, flags); > priv->phy_dev->drv = &priv->conv_phy_drv; > + spin_unlock_irqrestore(&priv->phy_lock, flags); And how is this spinlock protecting anything? > + > + dev_set_drvdata(dev, priv); > > return 0; > } > > +static void xgmiitorgmii_remove(struct mdio_device *mdiodev) > +{ > + struct gmii2rgmii *priv = dev_get_drvdata(&mdiodev->dev); > + struct mii_bus *bus; > + > + bus = priv->phy_dev->mdio.bus; > + > + put_device(&priv->phy_dev->mdio.dev); > + module_put(bus->owner); > + phy_disconnect(priv->phy_dev); Why are you disconnecting the phy? > +} > + > static const struct of_device_id xgmiitorgmii_of_match[] = { > { .compatible = "xlnx,gmii-to-rgmii-1.0" }, > {}, > @@ -107,6 +136,7 @@ MODULE_DEVICE_TABLE(of, xgmiitorgmii_of_match); > > static struct mdio_driver xgmiitorgmii_driver = { > .probe = xgmiitorgmii_probe, > + .remove = xgmiitorgmii_remove, > .mdiodrv.driver = { > .name = "xgmiitorgmii", > .of_match_table = xgmiitorgmii_of_match, > -- > 2.1.2 >
diff --git a/drivers/net/phy/xilinx_gmii2rgmii.c b/drivers/net/phy/xilinx_gmii2rgmii.c index 7336fd0..cdd9d95 100644 --- a/drivers/net/phy/xilinx_gmii2rgmii.c +++ b/drivers/net/phy/xilinx_gmii2rgmii.c @@ -34,6 +34,7 @@ struct gmii2rgmii { struct phy_driver *phy_drv; struct phy_driver conv_phy_drv; int addr; + spinlock_t phy_lock; }; static int xgmiitorgmii_read_status(struct phy_device *phydev) @@ -55,7 +56,7 @@ static int xgmiitorgmii_read_status(struct phy_device *phydev) val |= BMCR_SPEED1000; else if (phydev->speed == SPEED_100) val |= BMCR_SPEED100; - else + else if (phydev->speed == SPEED_10) val |= BMCR_SPEED10; err = mdiobus_write(phydev->mdio.bus, priv->addr, XILINX_GMII2RGMII_REG, @@ -71,6 +72,8 @@ int xgmiitorgmii_probe(struct mdio_device *mdiodev) struct device *dev = &mdiodev->dev; struct device_node *np = dev->of_node, *phy_node; struct gmii2rgmii *priv; + struct mii_bus *bus; + unsigned long flags; priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); if (!priv) @@ -88,17 +91,43 @@ int xgmiitorgmii_probe(struct mdio_device *mdiodev) return -EPROBE_DEFER; } + spin_lock_init(&priv->phy_lock); + + bus = priv->phy_dev->mdio.bus; + if (!try_module_get(bus->owner)) { + dev_err(dev, "failed to get the bus module\n"); + return -EIO; + } + + get_device(&priv->phy_dev->mdio.dev); + priv->addr = mdiodev->addr; priv->phy_drv = priv->phy_dev->drv; memcpy(&priv->conv_phy_drv, priv->phy_dev->drv, sizeof(struct phy_driver)); priv->conv_phy_drv.read_status = xgmiitorgmii_read_status; priv->phy_dev->priv = priv; + spin_lock_irqsave(&priv->phy_lock, flags); priv->phy_dev->drv = &priv->conv_phy_drv; + spin_unlock_irqrestore(&priv->phy_lock, flags); + + dev_set_drvdata(dev, priv); return 0; } +static void xgmiitorgmii_remove(struct mdio_device *mdiodev) +{ + struct gmii2rgmii *priv = dev_get_drvdata(&mdiodev->dev); + struct mii_bus *bus; + + bus = priv->phy_dev->mdio.bus; + + put_device(&priv->phy_dev->mdio.dev); + module_put(bus->owner); + phy_disconnect(priv->phy_dev); +} + static const struct of_device_id xgmiitorgmii_of_match[] = { { .compatible = "xlnx,gmii-to-rgmii-1.0" }, {}, @@ -107,6 +136,7 @@ MODULE_DEVICE_TABLE(of, xgmiitorgmii_of_match); static struct mdio_driver xgmiitorgmii_driver = { .probe = xgmiitorgmii_probe, + .remove = xgmiitorgmii_remove, .mdiodrv.driver = { .name = "xgmiitorgmii", .of_match_table = xgmiitorgmii_of_match,
This patch fixes the below race conditions in the driver. ---> Fix Opps after unload the driver as a module ---> Use spin locks where relevant. ---> Take reference on the external phy to prevent issues when phy driver is unloaded. Reported-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com> --- drivers/net/phy/xilinx_gmii2rgmii.c | 32 +++++++++++++++++++++++++++++++- 1 file changed, 31 insertions(+), 1 deletion(-)