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QNX Hypervisor
The QNX Hypervisor allows you to run multiple OSs on a target system so you can separate critical and non-critical functions, support a wide variety of applications, and reduce hardware costs.
QNX Hypervisor for Safety User's Guide
VM Configuration Reference
When you specify options to configure a qvm process, you are assembling and configuring the components of a virtual machine (VM) in which a guest will run.
reserve
Reserve specified locations in guest-physical memory and/or guest interrupts

QNX Momentics IDE User's Guide
This User's Guide describes version 7.1 of the Integrated Development Environment (IDE) that's part of the QNX Momentics tool suite.
QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running QNX Neutrino 7.1.
QNX Hypervisor
The QNX Hypervisor allows you to run multiple OSs on a target system so you can separate critical and non-critical functions, support a wide variety of applications, and reduce hardware costs.
- QNX Hypervisor for Safety User's Guide
  - Understanding QNX Virtual Environments
    QNX hypervisors are designed to meet the expectations of a hypervisor specified by the Popek/Goldberg Theorem.
  - QNX Hypervisor for Safety: Protection Features
    This chapter explains the main features used by the QNX Hypervisor for Safety to protect itself and its guests. Many of these features are part of the design, while others are configurable.
  - Configuration
    A QNX hypervisor, its qvm processes that create the VMs in which guests run, and these guests must be configured to work together.
  - Building a QNX Hypervisor for Safety system
    This chapter explains how to build (assemble) a QNX Hypervisor for Safety system and transfer a bootable image to a supported target platform.
  - Booting and Shutting Down
    This chapter describes how to boot and shut down a QNX hypervisor system.
  - Using Virtual Devices, Networking, and Memory Sharing
    This chapter describes how guests can discover and connect to vdevs and how they can use important hypervisor capabilities, such as networking and memory sharing.
  - Monitoring and Troubleshooting
    This chapter describes some tools and techniques you can use to monitor and troubleshoot your hypervisor system.
  - Performance Tuning
    This chapter describes common sources of overhead in a QNX hypervisor system, and strategies for reducing this overhead and optimizing system performance.
  - VM Configuration Reference
    When you specify options to configure a qvm process, you are assembling and configuring the components of a virtual machine (VM) in which a guest will run.
    - Configuration variables
      You can set configuration variables that affect qvm process instance, guest, CPU, and vdev behavior.
    - cmdline
      Pass a string to a guest as though the string had been entered from the command line
    - cpu
      Create a new vCPU in the VM
    - dryrun
      Initialize a VM without starting the guest
    - dump
      Write a dump file for the guest
    - gdb
      Enable guest debugging through GDB
    - generate
      Explicitly request the generation of the specified system information table type in the guest
    - load
      Copy the contents of a file into the guest system address space
    - logger
      Filter messages to the output, and specify the location where these messages are output
    - pass
      Configure physical devices or data blob types passed through from the host to a guest
    - ram
      Allocate RAM to the VM
    - reserve
      Reserve specified locations in guest-physical memory and/or guest interrupts
    - rom
      Allocate ROM to the VM
    - safety
      Specify how a qvm process instance responds if any component or vdev it uses isn't safety-certified
    - set
      Set the value of a configuration variable
    - suppress
      Explicitly request the suppression or generation of the specified system information table type in the guest
    - system
      Specify the name of the VM being configured by the present configuration file
    - tolerance
      Set how long the host system is allowed to delay notifying the hypervisor of a timer expiry
    - unsupported
      Specify what the hypervisor should do if it can't successfully complete the emulation of a guest instruction
    - user
      Assign the specified values to the user name, or to the user ID and group IDs of the qvm process instance
    - vdev
      Specify and configure virtual devices to include in the VM
  - Virtual Device Reference
    This chapter presents the virtual devices (vdevs) delivered with QNX hypervisors, and describes how to configure these vdevs.
  - Utilities and Drivers Reference
    This chapter describes the utilities and drivers delivered with the QNX hypervisor.
  - Terminology
    The following terms are used throughout the QNX hypervisor documentation.
- QNX Hypervisor for Safety Virtual Device Developer's Guide
- QNX Hypervisor for Safety Virtual Device Developer's API Reference
- QNX Hypervisor User's Guide
QNX Software in the Cloud
QNX Software in the Cloud enables developers to use the QNX software in Amazon Web Services (AWS) and Microsoft Azure (Azure).
QNX Advanced Virtualization Frameworks User's Guide
This User's Guide is aimed at all systems integrators and developers who want to design and build embedded systems using the QNX Advanced Virtualization Frameworks.
Typographical Conventions, Support, and Licensing
This section describes the typographical conventions used throughout the documentation and explains how to obtain technical support.

reserve

Reserve specified locations in guest-physical memory and/or guest interrupts

Synopsis:

reserve options

Options:

intr guest_intr

Prevent the qvm process from allocating a guest interrupt with the number specified by guest_intr.

loc location_spec [,length]

Prevent the qvm process from allocating the location specified by location_spec.

If the reserved location is a PCI location (pci:), you must use the BDF specification form:

pci:bus_number:device_number[.function_number]

and not specify length.

If the reserved location is a memory location (mem:), you must specify length.

For more information about locations, see Guest resource types in the Configuration chapter.

Description:

The reserve option reserves locations in guest-physical memory and/or guest interrupts to prevent the qvm process from allocating them to any component or device.

If a guest OS expects that specific locations will hold some predetermined artifact (such as a table), or that specific interrupts will be used for some predetermined purposes, you should use the reserve option to ensure that when the qvm process assembles the VM for the guest it doesn't inadvertently allocate these locations and interrupts, and leaves them for you to allocate as your guest requires.

Any loc or intr option that follows a reserve option specifies a reserved location in guest-physical memory or a guest interrupt number.

The following examples illustrate how the reserve option can be used to reserve different types of resources:

Guest interrupt 39:
```
reserve intr 39
```
PCI device 1 on bus 0:
```
reserve loc pci:0:1
```
An x86 I/O region of eight bytes at 0xcf:
```
reserve loc io 0xcf,0x8
```
A memory region of eight bytes at 0x1000:
```
reserve loc 0x1000,0x8
```

Note:

The reserve option prevents the qvm process from dynamically allocating the locations and interrupts specified, but it doesn't prevent the qvm process from allocating the locations and interrupts if they are explicitly specified in the VM configuration.

Page updated: March 12, 2026