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Subject: Re: Compat 32-bit syscall entry from 64-bit task!?
From: "hpanvin@gmail.com" <hpa@zytor.com>
Date: Fri, 20 Jan 2012 15:58:21 -0800
To: Roland McGrath <mcgrathr@google.com>, Indan Zupancic <indan@nul.nu>
CC: Denys Vlasenko <vda.linux@googlemail.com>,
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Linus claims it does break.

Roland McGrath <mcgrathr@google.com> wrote:

>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.

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