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Date:   Tue, 13 Feb 2018 22:04:48 +0100
From:   Pavel Machek <pavel@ucw.cz>
To:     Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Cc:     tedheadster <tedheadster@gmail.com>, whiteheadm@acm.org,
        David Laight <David.Laight@aculab.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Ondrej Zary <linux@rainbow-software.org>,
        David Woodhouse <dwmw2@infradead.org>,
        Guenter Roeck <linux@roeck-us.net>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Hugh Dickins <hughd@google.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Jiri Kosina <jikos@kernel.org>, Borislav Petkov <bp@alien8.de>,
        Kees Cook <keescook@chromium.org>,
        Jamie Iles <jamie@jamieiles.com>,
        Eduardo Valentin <eduval@amazon.com>,
        Laura Abbott <labbott@redhat.com>,
        Rik van Riel <riel@surriel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [BUG] x86 : i486 reporting to be vulnerable to
 Meltdown/Spectre_V1/Spectre_V2
Message-ID: <20180213210448.GB6569@amd>
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On Thu 2018-02-08 20:52:40, Alan Cox wrote:
> > > Also worth nothing that the difference between the cpu and memory
> > > speeds is much lower - so far fewer instructions could be speculative=
ly
> > > executed while waiting a cache miss.
>=20
> 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.
>=20
> Meltdown we can at least reasonably test but spectre is hard.

Do you have pointer for simple meltdown test?

I've got https://github.com/IAIK/meltdown.git but could not get it to
work even on machines that should be vulnerable.
									Pavel
--=20
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo=
g.html

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