The Pentium F00F Bug

by Robert R. Collins



Example 1: 



Sequence  Address   Data      Mnemonic                             Timestamp

-----------------------------------------------------------------------------

T 524285  000000B2----7E--------(-IO-WRITE-)--------------------------300 ns

  524286  00000018  ----E14C    ( LOCKED MEM READ )                   440 ns

  524287  0000001A  F000----    ( LOCKED MEM READ )                   100 ns

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Example 2: 



Sequence  Address   Data      Mnemonic                              Timestamp

-----------------------------------------------------------------------------

  428677  00060FF8  0008049A    ( LOCKED MEM READ )                    330 ns

          00060FFC  00008E00    ( LOCKED MEM READ )

  428678  0001E8B8  BFF0FFFF    ( LOCKED MEM READ )                    170 ns

          0001E8BC  00009B01    ( LOCKED MEM READ )

  428679  0001EE9C  00000008    ( LOCKED MEM WRITE )                   130 ns

  428680  0001EE98  000003F2    ( MEM WRITE )                           60 ns

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Example 3: 



Sequence  Address   Data      Mnemonic                              Timestamp

-----------------------------------------------------------------------------

  429135  00060FF8  0008049A    ( LOCKED MEM READ )                    330 ns

          00060FFC  00008E00    ( LOCKED MEM READ )

  429136  0001E8B8  BFF0FFFF    ( LOCKED MEM READ )                    170 ns

          0001E8BC  00009B01    ( LOCKED MEM READ )

  429137  0001EE9C  00000008    ( LOCKED MEM WRITE )                   140 ns

  429138  0001EE98  000003F2    ( MEM WRITE )                           50 ns

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Example 4: 



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

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