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	Mon, 22 Apr 2013 06:34:45 -0400
From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Linux Media Mailing List <linux-media@vger.kernel.org>,
	Prabhakar Lad <prabhakar.csengg@gmail.com>
Subject: Re: [PATCH] V4L2: fix subdevice matching in asynchronous probing
Date: Mon, 22 Apr 2013 12:34:53 +0200
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Hi Guennadi,

On Friday 19 April 2013 16:41:02 Guennadi Liakhovetski wrote:
> A wrapped list iterating loop hasn't been correctly recognised in
> v4l2_async_belongs(), which led to false positives. Fix the bug by
> verifying the loop termination condition.
> 
> Reported-by: Prabhakar Lad <prabhakar.csengg@gmail.com>
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
> ---
> 
> Prabhakar, please, check, whether this fixes your problem.
> 
>  drivers/media/v4l2-core/v4l2-async.c |    4 ++++
>  1 files changed, 4 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/media/v4l2-core/v4l2-async.c
> b/drivers/media/v4l2-core/v4l2-async.c index 5d6b428..5631944 100644
> --- a/drivers/media/v4l2-core/v4l2-async.c
> +++ b/drivers/media/v4l2-core/v4l2-async.c
> @@ -76,6 +76,10 @@ static struct v4l2_async_subdev
> *v4l2_async_belongs(struct v4l2_async_notifier *
> 			break;
>  	}
> 
> +	if (&asd->list == &notifier->waiting)
> +		/* Wrapped - no match found */
> +		return NULL;
> +
>  	return asd;
>  }

What about just

                if (match && match(sd->dev, hw))
                        return asd;
        }

        return NULL;
}

That's a bit simpler.

-- 
Regards,

Laurent Pinchart