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you've ever done any programming in System
Management Mode, especially on the Pentium Pro
processor, then you must read this article.
In this article, I disclose
a bug in Intel's documentation that might help
you save dozens of hours debugging your code. In
the worst case, your code might actually appear
correct, but could cause system-wide failure;
even a processor shutdown.
Before wasting any
more time writing SMM code, you need to know all
of the facts. This article will be the first in a
series of articles about Intel's System
Management Mode on the Pentium Pro -- and all of
the details that Intel never told you.
few months ago, Intel's world was rocked with the
F00F bug fiasco. When encountered, bug was
capable of locking up an entire network. Any user
who had malicious intentions could write a
program which contained this specific opcode, and
bring down an entire network server.
Luckily, a few software
workarounds were discovered which would squash
this bug. And like usual, there's always a story
behind the story. This article has all of the
days before Intel's biggest processor
announcement in years, a math bug in the Pentium
Pro and Pentium II came to light. Robert takes
you inside the Dan-0411 "flag erratum,"
and tells how the story unfolded.
transitioning between 4MB pages and 4KB pages, it
is possible to retain the old page translations
in the TLB. This should be considered an anomaly,
at best. However, without specific knowledge of
this problem, it might come up and hit you when
you least expect it.
the thought of the FDIV bug sends shivers up most
peoples spine. In this article, I look into the
FDIV bug -- with my own unique perspective.
||Intel claims that using illegal
indices for RDMSR and WRMSR will result in a
general protection error (#GP(0)). However, as
this article shows, it is possible to access a
few MSRs that remain undocumented. Some of the
MSRs are actually useful and should be documented