Date: Thu, 12 Nov 2009 20:06:45 +0000
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: "Henrique de Moraes Holschuh" <hmh@hmh.eng.br>
Cc: "Andi Kleen" <andi@firstfloor.org>,
       "Robert Hancock" <hancockrwd@gmail.com>,
       "Anton D. Kachalov" <mouse@mayc.ru>, linux-kernel@vger.kernel.org
Subject: Re: Reading /dev/mem by dd
Message-ID: <20091112200645.700493c9@lxorguk.ukuu.org.uk>
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> Well, if debugging is the primary use, maybe the best long term plan
> would be to get rid of the need for /dev/mem for anything other than
> debugging, and after that is accomplished, move it to debugfs or make
> it optional?

/dev/mem is ABI and API. It's also part of Unix tradition and all sorts
of other stuff. It's just fine where it is.

> > The X case also involves X and the kernel both working with the same
> > resource and in many cases that resource having registers that can
> > crash a system if mis-accessed.
> 
> I see.  That also tells me that whatever dark sides KMS has, it is much
> better than the alternative :-)

Modern video doesn't really fit the simple kernel frame buffer model
anyway but it is important that the kernel now manages the resources for
all sorts of reasons including hotplug.
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