.. _SD.Security.PVAAuthentication:

.. include:: /content/swdocs.rsts

.. spelling::
   PVA
   VPI
   pva
   vpu
   sys

!!!!!!!!!!!!!!!!!!
PVA Authentication
!!!!!!!!!!!!!!!!!!

**Applies to** the Jetson Orin NX series, Jetson AGX Orin series, the Jetson Xavier NX series, and the Jetson AGX Xavier series.

Overview
@@@@@@@@

The Programmable Vision Accelerator (PVA) is a specialized engine to accelerate computer vision and image processing tasks.
Specialized software libraries such as `VPI <https://docs.nvidia.com/vpi/>`__ utilize the PVA.

By default, only signed application code is allowed to execute on the PVA hardware.
Software libraries provided by NVIDIA, such as VPI, will register signatures with the system when the libraries are installed by using a package manager on the target device.

Troubleshooting
@@@@@@@@@@@@@@@

Errors that occur while executing software that uses the PVA engine might be due to the incorrect signature registration.
To troubleshoot these issues, a privileged user can temporarily override the authentication mechanism by running the following command:

   $ sudo bash -c 'echo 0 > /sys/kernel/debug/pva0/vpu_app_authentication'

To enable authentication protection again, run the following command:

   $ sudo bash -c 'echo 1 > /sys/kernel/debug/pva0/vpu_app_authentication'

.. note:: On Xavier series, there is an additional PVA engine, so you need to run each command a second time with ``pva1`` instead of ``pva0``.