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Date: Tue, 31 Jul 2012 11:28:40 -0700
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Subject: Re: [PATCH] leds: triggers: send uevent when changing triggers
From: Colin Cross <ccross@android.com>
To: Bryan Wu <bryan.wu@canonical.com>
Cc: Greg KH <gregkh@linuxfoundation.org>, linux-kernel@vger.kernel.org,
        Henrique de Moraes Holschuh <hmh@hmh.eng.br>,
        Richard Purdie <rpurdie@rpsys.net>, linux-leds@vger.kernel.org
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On Thu, Jul 26, 2012 at 9:04 PM, Bryan Wu <bryan.wu@canonical.com> wrote:
> 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

Given the rejection of the other solutions to this problem, and chance
of getting this acked?