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Date: Mon, 23 Jan 2012 03:14:13 +0100
Subject: Re: Compat 32-bit syscall entry from 64-bit task!?
From: "Indan Zupancic" <indan@nul.nu>
To: "Roland McGrath" <mcgrathr@google.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>,
        "Denys Vlasenko" <vda.linux@googlemail.com>,
        "Linus Torvalds" <torvalds@linux-foundation.org>,
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On Sat, January 21, 2012 00:55, Roland McGrath 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.

Argh, sorry, I meant eflags.

I even checked how many bits are free in eflags and still wrote 'cs'.

Greetings,

Indan