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Date: Tue, 4 Sep 2012 11:46:18 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Manavendra Nath Manav <mnm.kernel@gmail.com>
Cc: kernelnewbies@kernelnewbies.org, linux-kernel@vger.kernel.org
Subject: Re: Why exported const value modified by another driver not updated
 in original driver
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On Tue, 4 Sep 2012 15:00:16 +0530
Manavendra Nath Manav <mnm.kernel@gmail.com> wrote:

> Hi,
> 
> I have declared a static const int variable in one driver and exported
> that variable symbol. In another driver i am modifying that variable.
> The other driver prints the modified value but the original driver
> retains the original value. When both virtual and physical addresses
> of the variable as seen by both drivers are same, how is this even
> possible. Is it a kernel bug?

It's const, why is it even a surprise. If you don't understand what is
going on then I suggest you disassemble the code. That will I think let
you understand what is going on.

Alan