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Date: Fri, 19 Jul 2013 15:51:30 +1000
From: Jason White <jason@jasonjgw.net>
To: speakup@linux-speakup.org
Subject: Re: OT: kernel oops
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Don Raikes <don.raikes@oracle.com> wrote:
> Ok so I get it, but the problem is that I am hooking into the sys_write systemcall, and it is by default cast to a const.
> 
> If I leave it as is, and cast the buf in my copy_to_user to a (char*) should that work?
> 

Try (void __user *)
which according to Linux Device Drivers is the correct type for copy_to_user.
> Sorry my knowledge of c is very limited :)

I would suggest reading a good book on the subject in that case.

A good knowledge of C is a prerequisite for what you are doing.