Direct port I/O under NT without a driver

Originally Posted by omega_red

Exception is generated when first running this, without relogging, as explained above (not sure why though). After logout/login all is OK here (xp sp2).

thank for your helping. well, i re-loggined! is hardware related? my pc is intel 2.8cg disabling ht. the interesting thing is if i run or attach it with any debugger the iopl will become 3. if run without debugger, context iopl got 0

any idea to help ? thanks for advance

the port i tried : 295h 296h

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ZwSetInformationProcess result: 0h (seem ok)

Trying direct IO...EFlags : 00010246 ExceptionCode:C0000096 (context iopl == 0 ?)