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Message-ID: <21d7e9970512061355o598dbbfkcd4bfb7140efb69c@mail.gmail.com>
Date: Wed, 7 Dec 2005 08:55:12 +1100
From: Dave Airlie <airlied@gmail.com>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Subject: Re: Linux in a binary world... a doomsday scenario
Cc: Lee Revell <rlrevell@joe-job.com>, Jeff Garzik <jgarzik@pobox.com>,
       Brian Gerst <bgerst@didntduck.org>,
       Arjan van de Ven <arjan@infradead.org>, "M." <vo.sinh@gmail.com>,
       Andrea Arcangeli <andrea@suse.de>,
       William Lee Irwin III <wli@holomorphy.com>,
       linux-kernel@vger.kernel.org
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>
> The risk is that by reading the disassembled binary and rewriting it a
> programming might actually be deemed to have copied code if they
> accidentally just reproduce the original implementation.
>
>
> Often of course disassembly is the hard way to solve the problem. Firing
> up the driver with analyser tools and studying how it works can be far
> more informative. With the ATI R3xx work asking the binary driver to
> draw a wide range of triangles and monitoring the command queue output
> for each request  provides very good info, while attempting to deciphers
> megabytes of windows 3D driver code, which is likely to contain self
> modifying or JIT generated pipelines, is going to be extremely hard
> work.
>

I can pretty much guarantee nobody is stupid enough to even think
about attaching a debugger or disassembler to fglrx, doing black-box
reverse engineering is sufficent for everything, and as the r300 is
derived in many respects from the r200, we have a lot of info from
it..

Dave.
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