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# CPU_BASED_UNCOND_IO

The value that controls whether executions of various I/O instructions cause VM exits.

```
var CPU_BASED_UNCOND_IO: UInt32 { get }
```

## Discussion

Must be `1`; the VM exits on the execution of the following I/O instructions: IN, INS/INSB/INSW/INSD, OUT, OUTS/OUTSB/OUTSW/OUTSD.

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