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Date:   Tue, 23 Jan 2018 14:57:17 +0000
From:   Alan Cox <gnomes@lxorguk.ukuu.org.uk>
To:     Joerg Roedel <joro@8bytes.org>
Cc:     Nadav Amit <nadav.amit@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@kernel.org>,
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        Andrea Arcangeli <aarcange@redhat.com>,
        Waiman Long <llong@redhat.com>, jroedel@suse.de
Subject: Re: [RFC PATCH 00/16] PTI support for x86-32
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On Mon, 22 Jan 2018 09:56:25 +0100
Joerg Roedel <joro@8bytes.org> wrote:

> Hey Nadav,
> 
> On Sun, Jan 21, 2018 at 03:46:24PM -0800, Nadav Amit wrote:
> > It does seem that segmentation provides sufficient protection from Meltdown.  
> 
> Thanks for testing this, if this turns out to be true for all affected
> uarchs it would be a great and better way of protection than enabling
> PTI.
> 
> But I'd like an official statement from Intel on that one, as their
> recommended fix is still to use PTI.
> 
> And as you said, if it turns out that this works only on some Intel
> uarchs, we can also detect it at runtime and then chose the fasted
> meltdown protection mechanism.

I'll follow this up and get an official statement.

Alan