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hi all,
another lame question: i'm unable to set vm flag and i dont know why.so, i invoke interupt,eflags are pushed onto stack.then i 'or' memory containing eflags.but when this eflags are poped back to its register, vm bit is still untouched.i know that i'm doing something terribly wrong, so can anyone please show me ho to do that?
thanks

Get yourself a copy of the Intel manuals. They explain everything you need to know.

Intel 3A: 15.2.1 Enabling Virtual-8086 Mode
The processor runs in virtual-8086 mode when the VM (virtual machine) flag in the EFLAGS register is set. This flag can only be set when the processor switches to a new protected-mode task or resumes virtual-8086 mode via an IRET instruction.
System software cannot change the state of the VM flag directly in the EFLAGS register (for example, by using the POPFD instruction)