From mboxrd@z Thu Jan  1 00:00:00 1970
From: Florian Weimer <fweimer-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Subject: Re: [RFC PATCH] getcpu_cache system call: caching current CPU number
 (x86)
Date: Tue, 21 Jul 2015 10:01:26 +0200
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On 07/21/2015 02:25 AM, Mathieu Desnoyers wrote:
> But I'm inclined to think that some aspect of the question eludes me,
> especially given the amount of interest generated by the gs-segment
> selector approach. What am I missing ?

%gs is not explicitly mentioned in the x86_64 psABI.  This probably led
to the assumption that it's unused.  I think that's not the right
conclusion to draw.

-- 
Florian Weimer / Red Hat Product Security