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Date: Wed, 8 Jan 2003 14:44:42 -0500 (EST)
From: "Richard B. Johnson" <root@chaos.analogic.com>
Reply-To: root@chaos.analogic.com
To: "H. Peter Anvin" <hpa@zytor.com>
cc: linux-kernel@vger.kernel.org
Subject: Re: tenth post about PCI code, need help
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Message-ID: <Pine.LNX.3.95.1030108143728.31888A-100000@chaos.analogic.com>
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On 8 Jan 2003, H. Peter Anvin wrote:

> Followup to:  <Pine.LNX.3.95.1030108132812.28791A-100000@chaos.analogic.com>
> By author:    "Richard B. Johnson" <root@chaos.analogic.com>
> In newsgroup: linux.dev.kernel
> > 
> > The problem is that he's discovered something that's not supposed
> > to be in the code. Only 32-bit accesses are supposed to be made to
> > the PCI controller ports. He has discovered that somebody has made
> > some 8-bit accesses that will not become configuration 'transactions'
> > because they are not 32 bits.
> > 
> 
> Right.  That's what the code is checking for.
> 
> 	-hpa

Somebody is very lucky the designer of the bus interface state-machine
let him get away with it. This is a borderline "insane instruction" that
could, on some (future?) machine, require a power-off to recover. This is
NotGood(tm). It's like testing a fuse by shorting out a circuit. If it
works, the circuit no longer works. If I doesn't, the circuit no longer
works. Some things should not be tested.

Cheers,
Dick Johnson
Penguin : Linux version 2.4.18 on an i686 machine (797.90 BogoMips).
Why is the government concerned about the lunatic fringe? Think about it.


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