Re: [PATCH] leds: triggers: send uevent when changing triggers

[Bryan Wu <bryan.wu@canonical.com>]

On Fri, Jul 27, 2012 at 12:51 AM, Greg KH <gregkh@linuxfoundation.org> wrote:
> On Thu, Jul 26, 2012 at 01:03:11PM +0800, Bryan Wu wrote:
>> Just one quick patch for my idea: emitting a uevent in sysfs_create_file().
>>
>> --
>> diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
>> index 00012e3..04da869 100644
>> --- a/fs/sysfs/file.c
>> +++ b/fs/sysfs/file.c
>> @@ -570,10 +570,14 @@ int sysfs_add_file(struct sysfs_dirent *dir_sd,
>> const struct attribute *attr,
>>
>>  int sysfs_create_file(struct kobject * kobj, const struct attribute * attr)
>>  {
>> +       int err = 0;
>> +
>>         BUG_ON(!kobj || !kobj->sd || !attr);
>>
>> -       return sysfs_add_file(kobj->sd, attr, SYSFS_KOBJ_ATTR);
>> +       err = sysfs_add_file(kobj->sd, attr, SYSFS_KOBJ_ATTR);
>> +       kobject_uevent(kobj, KOBJ_CHANGE);
>
> That's a veritable flood of change events when a new kobject is created,
> right?  It also created uevents for a device that has not told userspace
> that it is even present, which could cause massive confusion, don't you
> think?
>

Indeed, this is unacceptable. I reworked a new patchset and just sent
our for you review.

Thanks,
-Bryan