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From: Roland McGrath <mcgrathr@google.com>
Date: Fri, 20 Jan 2012 15:55:05 -0800
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Subject: Re: Compat 32-bit syscall entry from 64-bit task!?
To: Indan Zupancic <indan@nul.nu>
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On Fri, Jan 20, 2012 at 3:49 PM, Indan Zupancic <indan@nul.nu> wrote:
> It's a lot easier for existing code to add an extra cs check than to use

The issue is whether showing fictitious high bits of %cs as set will break
existing applications (debuggers, etc.) that look at it and think that it's
nothing but the hardware state zero-extended, as it is today.