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From: "Manfred Spraul" <manfred@colorfullife.com>
To: "Frank Cornelis" <Frank.Cornelis@rug.ac.be>
Cc: <linux-kernel@vger.kernel.org>
Subject: Re: ptrace on i386
Date: Sat, 1 Dec 2001 11:46:26 +0100
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>
> In linux/arch/i386/kernel/ptrace.c next code is being used in the xxxreg
> functions:
> 	if (regno > GS*4)
> 		regno -= 2*4;
> Why this discontinuity? 

Backward compatibility. The syscall entry point changed between 2.0 and 2.2, but
that change must remain invisible to user space apps. the "-= 2*4" converts old offsets
to new offsets (or the other way around)

--
    Manfred

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