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Subject: [MODERATED] Re: [PATCH 1/6] Patch 1
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From: Jon Masters <jcm@redhat.com>
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Date: Wed, 25 Apr 2018 23:39:57 -0400
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On 04/25/2018 11:22 PM, speck for Linus Torvalds wrote:

> I don't know. Maybe I'm missing something. But it *already* sounds=20
> impossible to use in practice,  and I pretty much guarantee that if you=
=20
> need terabytes of swap space in use on a desktop (and another 6-8 bits =
of=20
> physical addressing on the Xeons?) there is absolutely no way people wi=
ll=20
> have swap offsets big enough to ever hit the MAX_PA/2 bit.

A bunch of us (including Amazon) discussed this limitation (MAX_PA/2)
and it seemed somewhat academic that you'd be able to pull off an attack
at that point reliably. There doesn't seem to be any downside to adding
a vulnerable warning in sysfs in that case, which was also suggested.

Jon.

--=20
Computer Architect | Sent from my Fedora powered laptop


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