      (,   
 ).  pgd      -
 .         
 page_table_lock,      -
 .

 ,    ,    -
      <asm/page .h>.

        -
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      .    
      .   ,
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kaside buffer,  TLB),  ,     -
   .      
 ,       TLB.   
  ,      .   
       .

  ,       
   .    2.6   
      .  , ,  -
        .
          -
      fork ().   -
        , 
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  .      -
 ,        fork ().



       ,  -
  .  ,    
  (   struct mm_struct)   -
         (str-
uct vm_area_struct).    ,    ( 
 mmap ())   (   munmap ())  .  -
    .     Linux  
   ,        
     .

         , -
      -  
 .   !

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