PM / devfreq: Don't delete sysfs group twice

The 'userspace' governor adds a sysfs entry, which is removed when
the governor is changed, or the devfreq device is released. However,
when the latter occurs via device_unregister(), device_del() is
called first, which removes the sysfs entries recursively and deletes
the kobject.

This means we get an Oops when the governor calls
sysfs_remove_group() on the deleted kobject. Fix this by only doing
the call when kobj *hasn't* been kobject_del()'d.

Note that we can't just remove the call to sysfs_remove_group()
entirely - it's needed for when the governor is changed to one which
doesn't need a sysfs entry.

Signed-off-by: Chris Diamand <chris.diamand@arm.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
This commit is contained in:
Chris Diamand 2017-01-12 14:57:41 +00:00 committed by MyungJoo Ham
parent 566cf877a1
commit 924b9111a1

View file

@ -112,7 +112,13 @@ static int userspace_init(struct devfreq *devfreq)
static void userspace_exit(struct devfreq *devfreq)
{
sysfs_remove_group(&devfreq->dev.kobj, &dev_attr_group);
/*
* Remove the sysfs entry, unless this is being called after
* device_del(), which should have done this already via kobject_del().
*/
if (devfreq->dev.kobj.sd)
sysfs_remove_group(&devfreq->dev.kobj, &dev_attr_group);
kfree(devfreq->data);
devfreq->data = NULL;
}