notes.txt


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  /* Defenitions:
   *  Segment:
   *    A logically contiguous chunk of memory with consistent properties from the cpus perspective
   *    - Just a bunch of memory dedicated for a specific purpose
   *  Segment Register:
   *    A register of the CPU that refers to a segment for a particular purpose (CS, DS, SS, ES)
   *      or for general use. (FS, GS)
   *    - Code segment, Data segment, ...
   *  Segment Selector:
   *    A reference to a descriptor, which you can load into a segment register; the selector is an offset
   *    into a descriptor table pointing to one of its entries.
   *    These entries are typically 8 bytes long, therefore
   *      bits 3 and up only declare the descriptor table entry offset
   *      bit 2 specifies GDT or LDT
   *      bits 0-1 declare ring level that needs to correspond to the descriptor table entry's DPL field.
   *        GENERAL PROTECTION FAULT if it doesn't
   *        If it does correspond then the CPL level of the selector used is changed accordingly
   *    - A pointer to an entry in the DT
   *  Segment Descriptor:
   *    An entry in a descriptor table.
   *    These are a binary data structure that tells the CPU the attributes of a given segment
   *    - A binary number that describes a segment
   */