The Pentium F00F Bug

By Robert R. Collins

Dr. Dobb's Journal May 1998

Sequence  Address   Data      Mnemonic                        Timestamp
-------------------------------------------------------------------------
  426333  00060FF8  00080496    ( LOCKED MEM READ )               60 ns
          00060FFC  00008E00    ( LOCKED MEM READ )
  426334  0001E8B8  BFF0FFFF    ( LOCKED MEM READ )              170 ns
          0001E8BC  00009B01    ( LOCKED MEM READ )
  426335  0001EEA0  00010002    ( LOCKED MEM WRITE               120 ns
  426336  0001EE9C  00000008    ( MEM WRITE )                     60 ns
  426337  0001EE98  000003EE    ( MEM WRITE )                     50 ns

Example 4: F00F bug with cache disabled.

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