:: Re: [DNG] Meltdown and linux kernel…
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Author: Adam Borowski
Date:  
To: dng
Subject: Re: [DNG] Meltdown and linux kernel KPTI patch
On Fri, Jan 05, 2018 at 01:30:13PM -0800, Rick Moen wrote:
> Quoting Renaud (Ron) OLGIATI (renaud@???):
>
> > ISTR that AMDs are not affected by Meltdown, but affected by Spectre
>
> _Possibly_. Quoting the Meltdown FAQ: 'At the moment, it is unclear
> whether ARM and AMD processors are also affected by Meltdown.'
> https://meltdownattack.com/#faq


AMD engineers say none of their x86 CPUs are affected, as they check
permissions before speculating into.

A minority of ARM CPUs do suffer from Meltdown, see:
    https://developer.arm.com/support/security-update
for details.  Variant 3 is Meltdown.  Among these, only Cortex-A75 is
affected by attacks believed to be exploitable.


Intel's PR campaign keeps saying everywhere that AMD is affected, but that's
a bold-faced lie that hinges on the fact that one of experimental processors
by AMD (ARM-based Opteron A) is Cortex-A57 which has variant 3a.


On the other hand, indeed AMD (all or almost all) are affected by Spectre.


Basically only in-order CPUs are free of Spectre. Pinebook FTW!


Meow!
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