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To: Dmitry Morozovsky <marck@rinet.ru>
Subject: Re: DRAM Rowhammer exploits
In-reply-to: <alpine.BSF.2.00.1503092309570.38285@woozle.rinet.ru>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
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Date: Mon, 09 Mar 2015 20:45:09 +0000
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--------
In message <alpine.BSF.2.00.1503092309570.38285@woozle.rinet.ru>, Dmitry M=
orozo
vsky writes:
>On Mon, 9 Mar 2015, Poul-Henning Kamp wrote:
>
>> >any thoughts we're vulnerable to this?
>> =

>> It's a hardware problem, *everybody* are vulnerable.
>
>Well, it seems I used somewhat incorrect wordings.
>
>Any chance we could provide workaround like for Pentium f00f bug?

As far as I know the only workaround is increasing the DRAM refresh
rate sufficiently that the hardware behaves as it should.

It seems that such BIOS updates are being rolled out, but undoubtedly
a lot of old machines will get none and it's not even entirely obvious
that increasing the DRAM refresh rate is enough.

-- =

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    =

Never attribute to malice what can adequately be explained by incompetence=
.