L4T Kernel Builder

⚡ Quick Start

This script supports:

• ✅ Native compilation on Jetson
• 🔁 Cross-compilation on PC
• 📦 Building multiple kernel modules via modules.txt

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📄 Module Configuration

Before running, create a modules.txt file:

For example: CAN kernels

# module_name|config_symbol|module_dir

gs_usb|CONFIG_CAN_GS_USB|drivers/net/can/usb
peak_usb|CONFIG_CAN_PEAK_USB|drivers/net/can/usb

• module_name → output .ko name
• config_symbol → kernel config to enable
• module_dir → path inside kernel source

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📦 Native Compilation (on Jetson)

1. Clone the repository and run the build script

git clone https://github.com/pairlab/jetson-gs_usb-kernel-builder.git
cd jetson-gs_usb-kernel-builder

./jetson-gs_usb-kernel-builder.sh

✔️ Behavior

• Automatically detects Jetson L4T version
• Generates kernel config from /proc/config.gz
• Builds all modules listed in modules.txt
• Installs modules directly to system
• Adds them to /etc/modules
• Runs depmod

📌 Optional: Specify kernel version manually

./jetson-gs_usb-kernel-builder.sh --kernel-version 36.4.3

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🔁 Cross-Compilation Workflow (Jetson → Host → Jetson)

1. On Jetson: Export kernel config

zcat /proc/config.gz > config

2. Copy config file to your host machine

scp config user@host:/path/to/jetson-gs_usb-kernel-builder/

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3. On host: Clone the repository and run the build script

git clone https://github.com/pairlab/jetson-gs_usb-kernel-builder.git
cd jetson-gs_usb-kernel-builder

./jetson-gs_usb-kernel-builder.sh --kernel-version 36.4.3

✔️ Behavior

• Requires --kernel-version on PC
• Downloads matching:
  • public kernel sources
  • cross-compilation toolchain
• Builds all modules from modules.txt
• Outputs .ko files to current directory

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4. Copy modules back to Jetson

scp *.ko user@jetson:/home/user/

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5. Install modules on Jetson

sudo mkdir -p /lib/modules/$(uname -r)/kernel/<module-subdir>/
sudo cp *.ko /lib/modules/$(uname -r)/kernel/<module-subdir>/

echo "<module_name>" | sudo tee -a /etc/modules

sudo depmod -a
sudo reboot

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⚙️ Script Options

./jetson-gs_usb-kernel-builder.sh [OPTIONS]

Options:
  --kernel-version VERSION   Target L4T version (required for cross-compile)
  --modules-file FILE        Module definition file (default: modules.txt)
  -h, --help                 Show help

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📦 Supported Kernel Versions

This script uses a lookup table for NVIDIA releases to ensure the correct:

• public source package
• toolchain version

Currently supported:

• 36.4.3
• 36.4.4

To add support for a new version:

• Update resolve_release_info() in the script
• Verify URLs from NVIDIA Jetson Linux resources

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⚠️ Notes & Limitations

• Cross-compilation requires a valid config from the target Jetson
• Kernel version refers to the L4T version (for example 36.4.3), not uname -r
• Modules are installed automatically only in native mode
• Cross-compiled modules must be manually copied to Jetson

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💡 Tips

• Keep multiple modules.txt files for different projects or devices
• Version-control your module list for reproducibility
• Use native mode for quick iteration, and cross-compile for CI or faster builds