| Message ID | 1406144852-7379-3-git-send-email-ezequiel.garcia@free-electrons.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
2014-07-23 12:47 GMT-07:00 Ezequiel Garcia <ezequiel.garcia@free-electrons.com>: > This commit adds proper module_{get,put} to prevent the MDIO bus module > from being unloaded while the phydev is connected. By doing so, we fix > a kernel panic produced when a MDIO driver is removed, but the phydev > that relies on it is attached and running. > > Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Tested-by: Florian Fainelli <f.fainelli@gmail.com> Thanks Ezequiel! > --- > drivers/net/phy/phy_device.c | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c > index 4f4568e..1a5815c 100644 > --- a/drivers/net/phy/phy_device.c > +++ b/drivers/net/phy/phy_device.c > @@ -575,6 +575,7 @@ int phy_attach_direct(struct net_device *dev, struct phy_device *phydev, > u32 flags, phy_interface_t interface) > { > struct device *d = &phydev->dev; > + struct module *bus_module; > int err; > > /* Assume that if there is no driver, that it doesn't > @@ -599,6 +600,14 @@ int phy_attach_direct(struct net_device *dev, struct phy_device *phydev, > return -EBUSY; > } > > + /* Increment the bus module reference count */ > + bus_module = phydev->bus->dev.driver ? > + phydev->bus->dev.driver->owner : NULL; > + if (!try_module_get(bus_module)) { > + dev_err(&dev->dev, "failed to get the bus module\n"); > + return -EIO; > + } > + > phydev->attached_dev = dev; > dev->phydev = phydev; > > @@ -664,6 +673,10 @@ EXPORT_SYMBOL(phy_attach); > void phy_detach(struct phy_device *phydev) > { > int i; > + > + if (phydev->bus->dev.driver) > + module_put(phydev->bus->dev.driver->owner); > + > phydev->attached_dev->phydev = NULL; > phydev->attached_dev = NULL; > phy_suspend(phydev); > -- > 2.0.1 >
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index 4f4568e..1a5815c 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -575,6 +575,7 @@ int phy_attach_direct(struct net_device *dev, struct phy_device *phydev, u32 flags, phy_interface_t interface) { struct device *d = &phydev->dev; + struct module *bus_module; int err; /* Assume that if there is no driver, that it doesn't @@ -599,6 +600,14 @@ int phy_attach_direct(struct net_device *dev, struct phy_device *phydev, return -EBUSY; } + /* Increment the bus module reference count */ + bus_module = phydev->bus->dev.driver ? + phydev->bus->dev.driver->owner : NULL; + if (!try_module_get(bus_module)) { + dev_err(&dev->dev, "failed to get the bus module\n"); + return -EIO; + } + phydev->attached_dev = dev; dev->phydev = phydev; @@ -664,6 +673,10 @@ EXPORT_SYMBOL(phy_attach); void phy_detach(struct phy_device *phydev) { int i; + + if (phydev->bus->dev.driver) + module_put(phydev->bus->dev.driver->owner); + phydev->attached_dev->phydev = NULL; phydev->attached_dev = NULL; phy_suspend(phydev);
This commit adds proper module_{get,put} to prevent the MDIO bus module from being unloaded while the phydev is connected. By doing so, we fix a kernel panic produced when a MDIO driver is removed, but the phydev that relies on it is attached and running. Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com> --- drivers/net/phy/phy_device.c | 13 +++++++++++++ 1 file changed, 13 insertions(+)