Re: [PATCH] driver core: move uevent call to driver_register

From: Sebastian Ott
Date: Tue Jul 17 2012 - 04:52:10 EST


Hi,

On Tue, 17 Jul 2012, Ming Lei wrote:
> On Tue, Jul 3, 2012 at 1:08 AM, Sebastian Ott <sebott@xxxxxxxxxxxxxxxxxx> wrote:
>
> > --- a/drivers/base/driver.c
> > +++ b/drivers/base/driver.c
> > @@ -187,6 +187,9 @@ int driver_register(struct device_driver
> > ret = driver_add_groups(drv, drv->groups);
> > if (ret)
> > bus_remove_driver(drv);
> > +
> > + kobject_uevent(&drv->p->kobj, KOBJ_ADD);
>
> You should just send the uevent if 'ret' equals to zero., otherwise
> OOPS may be triggered by kobject_uevent() after the 'drv' has been
> removed.

oh..sorry. Missed that. Thanks for catching it!
Updated Patch:

[PATCH] driver core: move uevent call to driver_register

Device driver attribute groups are created after userspace is notified
via an add event. Fix this by moving the kobject_uevent call to
driver_register after the attribute groups are added.

Signed-off-by: Sebastian Ott <sebott@xxxxxxxxxxxxxxxxxx>
---
drivers/base/bus.c | 1 -
drivers/base/driver.c | 6 +++++-
2 files changed, 5 insertions(+), 2 deletions(-)

--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -743,7 +743,6 @@ int bus_add_driver(struct device_driver
}
}

- kobject_uevent(&priv->kobj, KOBJ_ADD);
return 0;

out_unregister:
--- a/drivers/base/driver.c
+++ b/drivers/base/driver.c
@@ -185,8 +185,12 @@ int driver_register(struct device_driver
if (ret)
return ret;
ret = driver_add_groups(drv, drv->groups);
- if (ret)
+ if (ret) {
bus_remove_driver(drv);
+ return ret;
+ }
+ kobject_uevent(&drv->p->kobj, KOBJ_ADD);
+
return ret;
}
EXPORT_SYMBOL_GPL(driver_register);

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/