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# hv_vm_protect(_:_:_:)

Modifies the permissions of a region in the guest physical address space of the VM.

```
func hv_vm_protect(_ ipa: hv_ipa_t, _ size: Int, _ flags: hv_memory_flags_t) -> hv_return_t
```

## Parameters

`ipa`

The address in the intermediate physical address space. It must be page-aligned.

    Apple silicon only.

`size`

The size in bytes of the region to protect, in bytes. It must be a multiple of the page size.

`flags`

The permissions for the protected region. For a list of valid options, see [`hv_memory_flags_t`](/documentation/Hypervisor/hv_memory_flags_t).

## Return Value

[`HV_SUCCESS`](/documentation/Hypervisor/HV_SUCCESS) if the operation was successful, otherwise an error code specified in [`hv_return_t`](/documentation/Hypervisor/hv_return_t).

## Discussion

Intel-based Mac computers have different parameters:

- `gpa`: The address in the guest physical address space. It must be page-aligned.

---

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