
Hidden Debug Mode Found In AMD Processors - nitam
http://www.woodmann.com/collaborative/knowledge/index.php/Super-secret_debug_capabilities_of_AMD_processors_!
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JoachimSchipper
Also see <http://news.ycombinator.com/item?id=1897583>.

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dredge
Google's cache has a forum thread on the site, which I suspect led to the
creation of the page linked above (which isn't yet cached)

[http://www.google.com/search?q=cache:www.woodmann.com/forum/...](http://www.google.com/search?q=cache:www.woodmann.com/forum/archive/index.php/t-13891.html)

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daeken
Anyone happen to know if this passes cleanly through AMD-V? There are a few
really cool debugging facilities on modern x86 processors (e.g. branch-wise
versus instruction-wise stepping) that aren't handled in any VM that I know
of.

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limmeau
Probably slashdotted -- I get a database error.

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rbanffy
Indeed: [http://hardware.slashdot.org/story/10/11/12/047243/Hidden-
De...](http://hardware.slashdot.org/story/10/11/12/047243/Hidden-Debug-Mode-
Found-In-AMD-Processors)

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limmeau
Apparently, Slashdot reader TheRaven64 has read the story. He summarizes it:

[http://hardware.slashdot.org/comments.pl?sid=1865066&cid...](http://hardware.slashdot.org/comments.pl?sid=1865066&cid=34206216)

(tldr: it's about DR0 working on more than one word)

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makmanalp
Hah, I can't believe woodmann.com is still alive. I used to read through
fravia's website's mirror there.

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makmanalp
Downvoted? What's wrong with what I said? I appreciated that site.

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ars
Because it has nothing to do with the topic, and especially because it doesn't
add anything to the discussion.

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Natsu
Well, fravia was a student of +ORC and a reverse engineer who put a lot of
information out there about reverse engineering at a time when there wasn't a
lot out there (i.e. 10+ years ago).

I guess he was just going for nostalgia, but I admit to being surprised that
people are still mirroring that. I've only had to reverse a few things, but I
have to say that that old information is still good, because it wasn't about
specific technology, but it was a more general sort of reasoning backwards
that allowed you to infer the inner workings of something by looking at it
from the outside. Even when I'm not trying to reverse something, I find it
useful: by reasoning about how things probably work internally, I can
sometimes discover features that no one bothered to document or things like
that.

