Orin Nano Unable to Handle Kernel Page Request

Issue Overview

Users of the Nvidia Jetson Orin Nano Dev board are experiencing kernel crashes when attempting to capture images from a v4l2 device using a C++ implementation. The issue manifests during the initialization and image reception phases, resulting in a system reboot and incomplete error messages. Specifically, the kernel logs indicate an "Unable to handle kernel paging request" at a consistent virtual address (0000000000140000) and various memory abort information, suggesting a serious fault in memory handling. The issue has been reported to occur consistently when using the USER_PTR method to transfer images directly to CUDA memory, while using the v4l2-ctl command works without issues for multiple captures. This discrepancy highlights potential problems with the C++ code or its interaction with the hardware or drivers.

Possible Causes

1. Hardware Incompatibilities: The Orin Nano may have different hardware specifications compared to older models like the Xavier NX, leading to incompatibilities in how memory is accessed or managed.

2. Software Bugs or Conflicts: The kernel version or drivers used may contain bugs that affect memory management, especially when using specific methods like USER_PTR.

3. Configuration Errors: Incorrect configuration of buffers or settings in the C++ implementation could lead to improper memory access.

4. Driver Issues: The drivers for the v4l2 device may not be fully compatible with the Orin Nano, causing crashes when certain functions are called.

5. Environmental Factors: Power supply issues or overheating could potentially cause instability during image processing tasks.

6. User Errors or Misconfigurations: Misusing APIs or incorrect parameters in system calls (e.g., ioctl) could lead to invalid arguments and crashes.

Troubleshooting Steps, Solutions & Fixes

1. Check Sample Code:

   • Review Nvidia’s MMAPI sample code, particularly 12_v4l2_camera_cuda and 18_v4l2_camera_cuda_rgb, which may provide insights into proper buffer initialization and configuration.

2. Modify Buffer Method:

   • Instead of using USER_PTR, try switching to DMA or MMAP methods for image transfer as these are more stable on the Orin Nano.

3. Run Diagnostics:

   • Use dmesg to gather kernel logs before crashes occur. This can help pinpoint specific errors related to memory access.
   • Example command:

     dmesg | grep -i 'error\|oops\|fault'
     

4. Test with Default Parameters:

   • Run the application with default parameters (without -u -z options) to see if it stabilizes the operation.

5. Isolate Variables:

   • Test different configurations by changing hardware components (e.g., using different cameras) or software setups (e.g., switching between JetPack versions).

6. Update Drivers and Firmware:

   • Ensure that all drivers and firmware are up-to-date with the latest versions available from Nvidia’s website.

7. Use Alternative Development Environments:

   • If developing on Ubuntu 22.04 proves problematic, consider using Docker containers or a different Linux distribution that is known to work well with Jetson devices.

8. Consult Documentation and Community Forums:

   • Review Nvidia’s official documentation for any updates regarding known issues with JetPack versions.
   • Engage with community forums for shared experiences and solutions from other users facing similar issues.

9. Best Practices for Future Development:

   • Follow Nvidia’s guidelines for memory management when working with CUDA and v4l2.
   • Regularly back up your configurations and document changes made during testing for future reference.

10. Unresolved Aspects:

    • Further investigation may be needed into whether specific kernel versions are more stable than others when interfacing with v4l2 devices.
    • Consider reaching out directly to Nvidia support for unresolved kernel issues that persist despite following troubleshooting steps.

By following these structured troubleshooting steps and considering potential causes, users can better diagnose and resolve kernel paging request issues encountered on the Nvidia Jetson Orin Nano Dev board.