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Date: Thu, 1 May 2014 23:51:39 +0200
From: Andi Kleen <andi@firstfloor.org>
To: Andy Lutomirski <luto@amacapital.net>
Cc: Andi Kleen <andi@firstfloor.org>, "H. Peter Anvin" <hpa@zytor.com>,
        X86 ML <x86@kernel.org>,
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        Andi Kleen <ak@linux.intel.com>
Subject: Re: [PATCH 4/7] x86: Add support for rd/wr fs/gs base
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> Allowing userspace to prevent itself from being rescheduled by loading
> something strange into gsbase seems unfortunate.

The timer tick will eventually catch it, so any delay is tightly
bounded.

Also still gets rescheduled most of the time, just not when a paranoid 
exception handler is running.

-Andi