Caveats of VME (when CR4.VME=1)

VME is wonderful for reducing the complexity of the OS, but isn't without its caveats. Some of the quirks are natural extensions of VME or the underlying architecture, while others might not make any sense.


  1. An undocumented opcode which generates an INT-1 exception. Also known as ICEBP.
  2. Opcodes 0xF1, 0xCC, 0xCE, 0x62 respectively.
  3. Assuming that all other protection attributes will permit the transition to occur.

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