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Date: Wed, 2 Jan 2013 09:28:54 +0000
From: Russell King - ARM Linux <linux@arm.linux.org.uk>
To: Julia Lawall <julia.lawall@lip6.fr>
Cc: Tony Prisk <linux@prisktech.co.nz>,
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Subject: Re: [PATCH RESEND 6/6] clk: s5p-g2d: Fix incorrect usage of
	IS_ERR_OR_NULL
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On Wed, Jan 02, 2013 at 08:29:57AM +0100, Julia Lawall wrote:
> There are dereferences to the result of clk_get a few times.  I tried the 
> following semantic patch:

And those are buggy; struct clk is _SUPPOSED_ to be an OPAQUE COOKIE
and no one other than the clk code should be dereferencing it.

I guess this is the danger of the common clk API - we now have a struct
clk that is exposed in a linux/*.h include which anyone can include, and
now anyone can get a definition for a struct clk and dereference it,
destroying opaqueness of this cookie.