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Date: Tue, 26 Apr 2016 13:50:30 -0700
From: Andi Kleen <andi@firstfloor.org>
To: Andy Lutomirski <luto@kernel.org>
Cc: x86@kernel.org, linux-kernel@vger.kernel.org,
        Borislav Petkov <bp@alien8.de>, Brian Gerst <brgerst@gmail.com>,
        Andi Kleen <andi@firstfloor.org>
Subject: Re: [PATCH 5/8] x86/arch_prctl/64: Remove FSBASE/GSBASE < 4G
 optimization
Message-ID: <20160426205030.GI13997@two.firstfloor.org>
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On Tue, Apr 26, 2016 at 12:23:28PM -0700, Andy Lutomirski wrote:
> As far as I know, the optimization doesn't work on any modern distro
> because modern distros use high addresses for ASLR.  Remove it.

I disagree with this patch. For example it will be a regression
for static executables.  And randomly making old systems slower is a bad
idea.

-Andi