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Date:   Thu, 8 Feb 2018 20:52:40 +0000
From:   Alan Cox <gnomes@lxorguk.ukuu.org.uk>
To:     tedheadster <tedheadster@gmail.com>
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        Hugh Dickins <hughd@google.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
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        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [BUG] x86 : i486 reporting to be vulnerable to
 Meltdown/Spectre_V1/Spectre_V2
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> > Also worth nothing that the difference between the cpu and memory
> > speeds is much lower - so far fewer instructions could be speculatively
> > executed while waiting a cache miss.

But they also have more instructions that take a lot of clocks and are
easier to stall - eg by doing things like opening and mmapping
a framebuffer and then doing a floating point double store to it
misaligned.

Meltdown we can at least reasonably test but spectre is hard.

Alan