Reason for x86 descriptor type priority over present? \ VOGONS

Reason for x86 descriptor type priority over present?

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First post, by superfury

Posted on 2019-08-12, 08:37

superfury Offline

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Why does the type check have priority over the present bit check? If it isn't present, then wouldn't the type be invalid anyways? Why does it throw #GP(selector) instead of #NP(selector) when both are the case?

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Reply 1 of 1, by peterferrie

Posted on 2019-08-13, 20:55

peterferrie Offline

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I suppose that checking present first might trigger someone to try to bring it into memory before finding that it's not usable anyway.

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