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Date: Wed, 30 Apr 2008 10:57:19 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
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Cc: Thomas Gleixner <tglx@linutronix.de>, Yinghai Lu <yhlu.kernel@gmail.com>,
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Subject: Re: [PATCH] x86: mtrr cleanup for converting continuous to discrete
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> The best definition I have heard of SMM mode is: smack the stupid OS
> that isn't doing what it should be doing at runtime mode.

Its also used for all sorts of ugly horrible hacks - like some boards
with broken latches on timers where the firmware uses SMM to emulate the
hardware and spins until the low byte flips before loading the time into
the RTC.

Thankfully on the newest cpus SMM mode is a bit more elegantly designed,
the original is a weird not quite real mode with extra bugs while nowdays
its more of a virtual machine