Re: [RFC PATCH 00/16] PTI support for x86-32

From: Alan Cox
Date: Thu Jan 25 2018 - 12:11:59 EST


On Mon, 22 Jan 2018 09:56:25 +0100
Joerg Roedel <joro@xxxxxxxxxx> 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.

It is: we don't think segmentation works on all processors as a defence.

Alan