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 Post subject: Error in IDT wiki article
PostPosted: Mon Aug 02, 2010 2:17 am 
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Hello. I found a small error in the IDT article in the wiki. IDTR's base field is a linear (not physical) address. Also, Is it correct what it says about bits 0..2? And shouldn't size be sizeof(idt) - 1?

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 Post subject: Re: Error in IDT wiki article
PostPosted: Mon Aug 02, 2010 2:27 am 
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Oh, I just realized those fields are in the register, and they're not necessarily the same the structure you have in memory and load using lidt has. Anyway, in the "Loading/Storing" section, it says the offset is "the virtual address of the table itself", and it should say "linear".

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 Post subject: Re: Error in IDT wiki article
PostPosted: Mon Aug 02, 2010 3:26 am 
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Joined: Thu Mar 25, 2010 11:26 pm
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Location: Melbourne, Australia
Quote:
IDTR's base field is a linear (not physical) address.
Correct, it's linear, not physical, not segment relative.
Quote:
Also, Is it correct what it says about bits 0..2?
No, I don't think so. All bits would be needed especially since the limit will always be an odd number I think.
Quote:
And shouldn't size be sizeof(idt) - 1?
Yes, meaning the limit is always odd.

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 Post subject: Re: Error in IDT wiki article
PostPosted: Wed Apr 25, 2012 12:35 pm 
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And at least one more thing: in the article we can read that non-present entry causes #GPF but if we look into AMD manual vol2 chapter 8.2.12 we'll see:
Quote:
An #NP occurs when an attempt is made to load a segment or gate with a clear present bit, as described
in the following situations:
...
- Referencing a gate descriptor containing a clear present bit.


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