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Subject: Re: Intel CPU design flaw - FreeBSD affected?
To: Cy Schubert <Cy.Schubert@komquats.com>, Warner Losh <imp@bsdimp.com>
Cc: FreeBSD Current <freebsd-current@freebsd.org>
References: <20180103001949.6AF4F2C9@spqr.komquats.com>
From: Michael Butler <imb@protected-networks.net>
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Date: Tue, 2 Jan 2018 19:56:48 -0500
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On 01/02/18 19:20, Cy Schubert wrote:
> This Linux commit gives us a hint.
> 
> https://lkml.org/lkml/2017/12//27/2

Sadly, the articles I've read to date make no mention of which Intel
silicon revs are vulnerable. However, the use of the PCID feature, which
is only available on more recent CPUs, does seem to afford a slightly
lesser performance hit when completely splitting the kernel and user
address space mappings :-(

	imb