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Date: Wed, 14 May 2008 09:34:13 +0800
From: "Dave Young" <hidave.darkstar@gmail.com>
To: "Greg KH" <greg@kroah.com>
Subject: Re: [PATCH 2/3] struct class sem to mutex converting
Cc: gregkh@suse.de, linux-kernel@vger.kernel.org,
       "Andrew Morton" <akpm@linux-foundation.org>
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On Wed, May 14, 2008 at 6:01 AM, Greg KH <greg@kroah.com> wrote:
> On Fri, May 09, 2008 at 03:22:31PM +0800, Dave Young wrote:
>  > The class_device is already removed, so do the class->sem to mutex converting.
>
>  Are you sure this will work?  Have you tried running lockdep to verify
>  that there are no problems here?  People have tried this in the past
>  with devices and I don't think it will work here either :(

Yes, lockdep doesn't generate warnings on my side.

I ever wanted to do the conversion, please see:
http://lkml.org/lkml/2008/1/12/49

The result is that device sem2mutex is not possible now, but class
sem2mutex is possible.  After the class_device removing, all the
class->sem usage exist in class.c except for i2c part.

So I make i2c to use class_for_each_device api, so we can do the
class->sem conversion.

>
>  thanks,
>
>  greg k-h
>