linux-input.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Daniel Mack <daniel@zonque.org>
To: Matt Ranostay <mranostay@gmail.com>,
	Jacek Anaszewski <j.anaszewski@samsung.com>
Cc: Daniel Mack <zonque@gmail.com>,
	Dmitry Torokhov <dmitry.torokhov@gmail.com>,
	"linux-input@vger.kernel.org" <linux-input@vger.kernel.org>,
	linux-leds@vger.kernel.org,
	"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>
Subject: Re: [PATCH v3 2/2] cap11xx: add LED support
Date: Mon, 15 Jun 2015 11:03:09 +0200	[thread overview]
Message-ID: <557E94CD.30705@zonque.org> (raw)
In-Reply-To: <CAKzfze8E-22XxzGuMUJWhcpmdoA=63XWR-v+bpf+Cdn70VoJqA@mail.gmail.com>

On 06/15/2015 10:56 AM, Matt Ranostay wrote:
> On Mon, Jun 15, 2015 at 1:15 AM, Jacek Anaszewski
> <j.anaszewski@samsung.com> wrote:

>>> +               error = devm_led_classdev_register(dev, &led->cdev);
>>> +               if (error < 0)
>>> +                       return -EINVAL;
>>> +               INIT_WORK(&led->work, cap11xx_led_work);
>>> +               schedule_work(&led->work);
>>
>>
>> Work queue should be initialized before registration of the LED class
>> device.
> What is the reason for this? Just curious

It's a race condition. The LED device is accessible once
devm_led_classdev_register() returns. So a user could be calling into
cap11xx_led_set() before the work queue is initialized, which would
hence access a NULL pointer.


Daniel


  reply	other threads:[~2015-06-15  9:03 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-06-13  4:17 [PATCH v3 0/2] cap11xx: Add LED support to driver Matt Ranostay
2015-06-13  4:17 ` [PATCH v3 1/2] dt: add cap11xx LED documentation Matt Ranostay
2015-06-15  8:15   ` Jacek Anaszewski
     [not found]     ` <557E8990.5060702-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
2015-06-15  8:48       ` Matt Ranostay
2015-06-15 10:10         ` Jacek Anaszewski
2015-06-15 17:00           ` Matt Ranostay
2015-06-13  4:17 ` [PATCH v3 2/2] cap11xx: add LED support Matt Ranostay
2015-06-15  8:15   ` Jacek Anaszewski
2015-06-15  8:56     ` Matt Ranostay
2015-06-15  9:03       ` Daniel Mack [this message]
2015-06-15 17:01         ` Matt Ranostay
2015-06-15 10:11       ` Jacek Anaszewski
2015-06-15 17:02         ` Matt Ranostay

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=557E94CD.30705@zonque.org \
    --to=daniel@zonque.org \
    --cc=devicetree@vger.kernel.org \
    --cc=dmitry.torokhov@gmail.com \
    --cc=j.anaszewski@samsung.com \
    --cc=linux-input@vger.kernel.org \
    --cc=linux-leds@vger.kernel.org \
    --cc=mranostay@gmail.com \
    --cc=zonque@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).