slideep/JETSON_FLASH_WSL2_GUIDE.md

Flashing NVIDIA Jetson Orin Nano (reComputer J3011) from Windows Using WSL2

A complete technical guide to flashing JetPack 6.1 on a Seeed Studio reComputer J3011 using only Windows + WSL2 — no native Linux machine required.

Overview
Hardware & Software Inventory
Architecture Overview
Phase 1: Environment Setup
Phase 2: Download & Prepare L4T BSP
Phase 3: Recovery Mode & USB Passthrough
Phase 4: Flash Attempts & Troubleshooting
Phase 5: Building a Custom WSL2 Kernel with RNDIS Support
Phase 6: Successful Flash
Post-Flash Verification
Troubleshooting Reference
Quick Reference: Reflash Procedure
Key Takeaways

Overview

The Challenge

NVIDIA's official Jetson flashing tools (l4t_initrd_flash.sh) are designed for native Linux hosts. The toolchain uses USB recovery mode (RCM), boots a Linux initrd onto the Jetson via USB, then establishes a USB RNDIS network link between the host and device to transfer flash images via SSH/SCP.

The problem: WSL2's default kernel does not include the CONFIG_USB_NET_RNDIS_HOST driver. Without it, the host cannot create the usb0 network interface needed to communicate with the Jetson during initrd flash. This guide documents how we solved this — and every obstacle along the way.

The Solution (TL;DR)

Install usbipd-win to forward USB devices from Windows to WSL2
Build a custom WSL2 kernel with RNDIS network driver support
Use NVIDIA's l4t_initrd_flash.sh inside WSL2 to flash the Jetson

Result

Successfully flashed JetPack 6.1 (L4T R36.4.0) onto a reComputer J3011 (Orin Nano 8GB, NVMe) entirely from Windows + WSL2.

Hardware & Software Inventory

Hardware

Component	Details
Jetson Module	NVIDIA Orin Nano 8GB (boardid: 3767, boardsku: 0003, chipsku: D5)
Carrier Board	Seeed Studio J401 (reComputer J3011 enclosure)
Storage	128GB NVMe SSD (internal to reComputer)
Host PC	Windows laptop with USB-A/USB-C ports
USB Cable	USB-C (Jetson) to USB-A (host) data cable
Jumper Wire	For shorting FC REC to GND (recovery mode)

Software

Component	Version
Windows	10.0.26300.7733
WSL2	v2.6.3.0, kernel 6.6.87.2-microsoft-standard-WSL2
WSL2 Distro	Ubuntu 26.04 "Resolute Raccoon"
usbipd-win	v5.3.0
L4T BSP	R36.4.0 (JetPack 6.1), released Sep 13 2024
GCC (for kernel build)	gcc-13 (13.4.0) — see GCC 15 incompatibility

Architecture Overview

Data Flow During Initrd Flash

┌─────────────────────────────────────────────────────────────────┐
│                        WINDOWS HOST                             │
│                                                                 │
│  ┌──────────────┐     USB/IP      ┌──────────────────────────┐  │
│  │  usbipd-win  │◄──────────────►│        WSL2 Ubuntu        │  │
│  │  (service)   │   (forwarding)  │                          │  │
│  │              │                 │  ┌────────────────────┐  │  │
│  │  BUSID 1-1   │                 │  │  vhci_hcd (USB/IP) │  │  │
│  │  auto-attach │                 │  │  rndis_host.ko ◄───┼──┼──── Custom kernel module
│  └──────┬───────┘                 │  │  usbnet.ko         │  │  │
│         │                         │  │  cdc_ether.ko      │  │  │
│         │ Physical USB            │  │  mii.ko            │  │  │
│         │                         │  └────────┬───────────┘  │  │
│         │                         │           │ usb0         │  │
│         │                         │  ┌────────▼───────────┐  │  │
│         │                         │  │ l4t_initrd_flash.sh│  │  │
│         │                         │  │  ├─ tegraflash.py  │  │  │
│         │                         │  │  ├─ SSH/SCP ───────┼──┼──── Over usb0 RNDIS
│         │                         │  │  └─ NFS server     │  │  │
│         │                         │  └────────────────────┘  │  │
│         │                         └──────────────────────────┘  │
└─────────┼───────────────────────────────────────────────────────┘
          │
          │ USB-C Cable
          │
┌─────────▼───────────────────────────────────────────────────────┐
│                    JETSON ORIN NANO (J3011)                      │
│                                                                 │
│  Phase 1: APX Recovery Mode (VID:PID 0955:7523)                 │
│    └─► RCM boot: Host sends initrd kernel via USB               │
│                                                                 │
│  Phase 2: Initrd Flash Mode (VID:PID 0955:7035)                 │
│    └─► USB re-enumerates as RNDIS network device                │
│    └─► Host establishes usb0 network link (192.168.55.1)        │
│    └─► Host SSHes into Jetson initrd environment                │
│    └─► Flash images transferred via SSH/SCP/NFS                 │
│    └─► Partitions written to QSPI (internal) + NVMe             │
│                                                                 │
│  Phase 3: Reboot into flashed OS                                │
│    └─► JetPack 6.1 boots from NVMe                              │
└─────────────────────────────────────────────────────────────────┘

USB Device State Transitions During Flash

Power On + FC REC → GND
        │
        ▼
  ┌─────────────┐     tegraflash.py rcmboot
  │ APX Mode    │─────────────────────────────►┌──────────────┐
  │ 0955:7523   │                              │ Initrd Boot  │
  │ (Recovery)  │                              │ 0955:7035    │
  └─────────────┘                              │ (RNDIS)      │
                                               └──────┬───────┘
                                                      │
                                     SSH over usb0    │  Flash partitions
                                                      │
                                               ┌──────▼───────┐
                                               │ Reboot       │
                                               │ Normal OS    │
                                               │ (JetPack)    │
                                               └──────────────┘

Critical insight: The USB device re-enumerates (disconnects and reconnects with a different VID:PID) during flash. This is why usbipd --auto-attach is essential — it must re-bind and re-attach the new device automatically.

Phase 1: Environment Setup

Step 1.1: Verify WSL2

# Check WSL version and kernel
wsl --version
wsl -d Ubuntu -- uname -r
# Expected: 6.6.87.2-microsoft-standard-WSL2

Step 1.2: Install usbipd-win

winget install usbipd
# Installed: usbipd-win v5.3.0

usbipd-win creates a Windows service that forwards USB devices to WSL2 via the USB/IP protocol. WSL2 runs in a lightweight Hyper-V VM and doesn't have direct USB access — usbipd bridges this gap.

Step 1.3: Install Flash Dependencies in WSL2

sudo apt update
sudo apt install -y \
    qemu-user-static \
    sshpass \
    abootimg \
    nfs-kernel-server \
    libxml2-utils \
    network-manager \
    python3 \
    python3-yaml \
    usbutils \
    xxd \
    cpio \
    binutils \
    dosfstools \
    lbzip2 \
    libxml2-utils \
    netcat-traditional

Troubleshooting: Ubuntu 26.04 Quirks

Ubuntu 26.04 (development branch) introduced several breaking changes:

Issue	Symptom	Fix
`qemu-aarch64-static` missing	`apply_binaries.sh` fails	`ln -sf /usr/bin/qemu-aarch64 /usr/bin/qemu-aarch64-static`
`netcat` is virtual package	`apt install netcat` fails	Install `netcat-traditional` explicitly
`ssh-keygen -t dsa` removed	Recovery ramdisk generation fails	Patch the script (see Phase 4)
GCC 15 is default	Kernel build fails	Use `gcc-13` explicitly

Phase 2: Download & Prepare L4T BSP

Step 2.1: Download L4T R36.4.0

mkdir -p ~/jetson-flash && cd ~/jetson-flash

# BSP Driver Package (~677MB)
wget https://developer.nvidia.com/downloads/embedded/l4t/r36_release_v4.0/release/jetson_linux_r36.4.0_aarch64.tbz2

# Sample Root Filesystem (~1.7GB)
wget https://developer.nvidia.com/downloads/embedded/l4t/r36_release_v4.0/release/tegra_linux_sample-root-filesystem_r36.4.0_aarch64.tbz2

Step 2.2: Extract and Apply

# Extract BSP
tar xf jetson_linux_r36.4.0_aarch64.tbz2

# Extract rootfs into the BSP
cd Linux_for_Tegra/rootfs
sudo tar xpf ../../tegra_linux_sample-root-filesystem_r36.4.0_aarch64.tbz2

# Apply NVIDIA binaries to rootfs
cd ..
sudo ./apply_binaries.sh

Step 2.3: Configure Default User

# Pre-create user so first-boot wizard is skipped
sudo ./tools/l4t_create_default_user.sh \
    -u nvidia \
    -p nvidia \
    -n jetson-orin \
    --accept-license

Choosing the Correct Flash Target

L4T R36.x uses a different naming convention than JetPack 5.x:

JetPack Version	Target Name Format	Example
JP 5.x (L4T R35.x)	`p3509-a02+p3767-0000`	Plus-sign separated
JP 6.x (L4T R36.x)	`jetson-orin-nano-devkit`	Human-readable name

The target jetson-orin-nano-devkit auto-detects the module SKU via EEPROM (reading boardid=3767, boardsku=0003 at runtime).

Phase 3: Recovery Mode & USB Passthrough

Step 3.1: Enter Recovery Mode

The reComputer J3011 (J401 carrier board) has FC REC and GND pins on the board header.

┌─────────────────────────────┐
│     J401 Carrier Board      │
│                             │
│   [FC REC] ──jumper── [GND] │  ◄── Short these with a jumper wire
│                             │
│   Then power on / plug USB  │
└─────────────────────────────┘

Procedure:

Power off the Jetson completely
Connect a jumper wire between FC REC and GND
Connect USB-C cable between Jetson and host PC
Power on the Jetson

Step 3.2: Verify APX Device on Windows

usbipd list
# Should show:
# 1-1    0955:7523  APX                    Not shared

The NVIDIA APX device (VID:PID 0955:7523) indicates the Jetson is in USB recovery mode.

Step 3.3: Bind and Attach to WSL2

# Run in Administrator PowerShell:
usbipd bind --busid 1-1 --force

# Start auto-attach (keeps running, handles re-enumeration):
usbipd attach --wsl --busid 1-1 --auto-attach

Important: The --auto-attach flag is critical. During flash, the Jetson disconnects and reconnects as a different USB device (RNDIS). Auto-attach monitors the bus ID and re-attaches automatically.

Important: WSL2 must be running before usbipd attach. If you get "There is no WSL 2 distribution running", open a WSL terminal first: wsl -d Ubuntu -- sleep 999999

Step 3.4: Verify in WSL2

lsusb | grep -i nvidia
# Bus 001 Device 002: ID 0955:7523 NVIDIA Corp. APX

Phase 4: Flash Attempts & Troubleshooting

The Flash Command

cd ~/jetson-flash/Linux_for_Tegra

sudo ./tools/kernel_flash/l4t_initrd_flash.sh \
    --external-device nvme0n1p1 \
    -c tools/kernel_flash/flash_l4t_external.xml \
    -p "-c bootloader/generic/cfg/flash_t234_qspi.xml" \
    --showlogs \
    --network usb0 \
    jetson-orin-nano-devkit internal

Parameter breakdown:

Parameter	Purpose
`--external-device nvme0n1p1`	Flash the OS to the NVMe SSD
`-c flash_l4t_external.xml`	Partition layout for external (NVMe) storage
`-p "-c flash_t234_qspi.xml"`	QSPI flash layout for bootloader partitions
`--showlogs`	Verbose output
`--network usb0`	Use USB RNDIS network for image transfer
`jetson-orin-nano-devkit`	Target board configuration
`internal`	Flash internal (QSPI) bootloader partitions too

Flash Process Steps (What the Script Does)

Step 1: Generate flash packages
  ├─ Read device ECID, fuses, EEPROM
  ├─ Generate signed bootloader images
  ├─ Create recovery ramdisk
  ├─ Build system.img from rootfs (~7GB, takes 5-10 min)
  └─ Generate partition tables

Step 2: Generate RCM boot command line
  ├─ Prepare rcmboot blob
  └─ Save flash parameters

Step 3: Start the flashing process
  ├─ Boot Jetson via RCM with initrd kernel
  ├─ Wait for USB RNDIS device (usb0) ◄── THIS IS WHERE IT FAILS WITHOUT RNDIS
  ├─ Configure usb0 network (192.168.55.1)
  ├─ SSH into Jetson initrd environment
  ├─ Transfer images via SSH/SCP
  ├─ Write QSPI partitions (bootloader, BCT, firmware)
  ├─ Write NVMe partitions (APP/rootfs)
  └─ Reboot

Issue 1: Invalid Target Board Name

Symptom:

Error: Invalid target board: p3509-a02+p3767-0000

Root Cause: Used JetPack 5.x naming convention with L4T R36.x BSP.

Fix: Use jetson-orin-nano-devkit instead of p3509-a02+p3767-0000.

Issue 2: ssh-keygen -t dsa Fails

Symptom:

gzip: kernel/Image: not in gzip format
# (misleading — actual error is deeper in the recovery ramdisk generation)

Root Cause: Ubuntu 26.04's OpenSSH removed DSA key type support. The script ota_make_recovery_img_dtb.sh calls ssh-keygen -t dsa which fails, triggering a cascade of errors.

Fix: Patch the script:

# File: tools/ota_tools/version_upgrade/ota_make_recovery_img_dtb.sh
# Line 112: Replace:
#   ssh-keygen -t dsa -f ...
# With:
#   # DSA disabled on Ubuntu 26.04
#   true

Issue 3: "Waiting for target to boot-up..." Timeout

Symptom:

************************************
*  Step 3: Start the flashing process *
************************************
Waiting for target to boot-up...
Waiting for target to boot-up...
... (repeats for 120 seconds)
Timeout
Device failed to boot to the initrd flash kernel.

Root Cause: This is the critical failure. After RCM boot, the Jetson boots into initrd and re-enumerates as a USB RNDIS device (VID:PID 0955:7035). The flash script waits for a usb0 network interface to appear. But WSL2's default kernel lacks CONFIG_USB_NET_RNDIS_HOST, so the RNDIS device is never recognized as a network adapter.

Diagnosis:

# Check dmesg during the wait:
dmesg | grep -iE "usb|rndis"
# Shows USB device enumerated but no driver binds:
# usb 1-1: new high-speed USB device number 5 using vhci_hcd
# usb 1-1: SetAddress Request (5) to port 0
# (no rndis_host binding follows)

# Check kernel config:
zcat /proc/config.gz | grep RNDIS
# CONFIG_USB_NET_RNDIS_HOST is not set  ◄── THE PROBLEM

What the waiting code actually checks:

# From l4t_initrd_flash_internal.sh, line 508-520:
while IFS= read -r; do
    netpath=/sys/class/net/${REPLY}
    netconfiguration=$(get_udev_attribute "${netpath}" configuration)
    if [[ "${netconfiguration}" =~ RNDIS\+L4T${device_instance}.* ]]; then
        serialnumber="${netserialnumber}"
        break
    fi
done < <(ls /sys/class/net)

It iterates over network interfaces in /sys/class/net, looking for one whose USB configuration attribute matches RNDIS+L4T*. Without the RNDIS driver, no such interface exists.

Fix: Build a custom WSL2 kernel with RNDIS support → Phase 5.

Issue 4: GCC 15 Incompatible with Kernel 6.6

Symptom:

error: '-fzero-call-used-regs=' is not supported on this target

Root Cause: Ubuntu 26.04 ships GCC 15.2.0 as default. The WSL2 kernel (6.6.x) was built with GCC 11.2.0 and is not compatible with GCC 15.

Fix:

sudo apt install gcc-13
# Then build with:
make CC=gcc-13 HOSTCC=gcc-13 -j$(nproc) ...

Issue 5: Module Vermagic Mismatch (`+` Suffix)

Symptom:

insmod: ERROR: could not insert module rndis_host.ko: Unknown symbol in module

Root Cause: Building from a git checkout adds a + suffix to the kernel version (indicating "dirty tree"). The module vermagic becomes 6.6.87.2-microsoft-standard-WSL2+ while the running kernel is 6.6.87.2-microsoft-standard-WSL2 (no +).

Fix:

# Create empty .scmversion to suppress git dirty suffix
touch .scmversion

# Also fix cached version strings:
echo "6.6.87.2-microsoft-standard-WSL2" > include/config/kernel.release
echo '#define UTS_RELEASE "6.6.87.2-microsoft-standard-WSL2"' > include/generated/utsrelease.h

Note: Even with matching vermagic, force-loaded modules (with insmod --force) may have CRC mismatches on symbol versions, causing the RNDIS driver to fail to bind to USB devices. The definitive solution is to run the custom-built kernel, not just load modules into the stock kernel.

Issue 6: NFS Server Fails in WSL2

Symptom:

A dependency job for nfs-server.service failed.

Root Cause: The nfsd kernel module isn't loaded, so /proc/fs/nfsd can't be mounted.

Fix:

sudo modprobe nfsd
sudo mount -t nfsd nfsd /proc/fs/nfsd
sudo systemctl start nfs-server

Phase 5: Building a Custom WSL2 Kernel with RNDIS Support

This is the key enabling step for the entire operation.

Step 5.1: Clone WSL2 Kernel Source

cd ~
git clone --depth 1 --branch linux-msft-wsl-6.6.87.2 \
    https://github.com/microsoft/WSL2-Linux-Kernel.git wsl-kernel
cd wsl-kernel

Step 5.2: Configure the Kernel

# Start from running kernel's config
zcat /proc/config.gz > .config

# Enable RNDIS and dependencies (as modules, since USB itself is =m)
# Using menuconfig or manual edit:
scripts/config --module CONFIG_MII
scripts/config --module CONFIG_USB_USBNET
scripts/config --module CONFIG_USB_NET_CDCETHER
scripts/config --module CONFIG_USB_NET_RNDIS_HOST

# Prevent git dirty suffix
touch .scmversion

# Prepare build
make CC=gcc-13 HOSTCC=gcc-13 olddefconfig

Why modules (=m) not built-in (=y)? Because CONFIG_USB=m in the WSL2 kernel. When USB support itself is a module, all USB sub-drivers must also be modules — the build system enforces this automatically.

Step 5.3: Build the Kernel

# Build bzImage (~5-10 minutes)
make CC=gcc-13 HOSTCC=gcc-13 -j$(nproc) bzImage

# Build all modules
make CC=gcc-13 HOSTCC=gcc-13 -j$(nproc) modules

# Install modules to /lib/modules/
sudo make modules_install

Step 5.4: Install the Custom Kernel

# Copy bzImage to Windows filesystem
cp arch/x86/boot/bzImage /mnt/c/Users/<username>/wsl-kernel-rndis

Create C:\Users\<username>\.wslconfig:

[wsl2]
kernel=C:\\Users\\<username>\\wsl-kernel-rndis

# Restart WSL2 to use the new kernel
wsl --shutdown
# Then start WSL again
wsl -d Ubuntu

Step 5.5: Verify and Load Modules

# Verify custom kernel is running
uname -r
# 6.6.87.2-microsoft-standard-WSL2+

cat /proc/version
# Should show your username and gcc-13

# Load RNDIS modules
sudo modprobe rndis_host

# Verify
lsmod | grep -iE "rndis|usbnet|cdc_ether|mii"
# rndis_host    20480  0
# cdc_ether     24576  1 rndis_host
# usbnet        61440  2 rndis_host,cdc_ether
# mii           20480  1 usbnet

Module Dependency Chain

┌──────────┐
│   mii    │  Media Independent Interface (Ethernet PHY)
└────┬─────┘
     │ depends
┌────▼─────┐
│  usbnet  │  USB network driver framework
└────┬─────┘
     │ depends
┌────▼──────┐
│ cdc_ether │  CDC Ethernet (USB networking base class)
└────┬──────┘
     │ depends
┌────▼───────────┐
│  rndis_host    │  Remote NDIS host driver (Microsoft USB networking)
└────────────────┘

Phase 6: Successful Flash

Pre-Flight Checklist

# 1. Custom kernel running
uname -r  # Should show your custom build

# 2. RNDIS modules loaded
lsmod | grep rndis_host  # Should show rndis_host

# 3. NFS server running
sudo modprobe nfsd
sudo mount -t nfsd nfsd /proc/fs/nfsd 2>/dev/null
sudo systemctl start nfs-server

# 4. Jetson in APX mode
lsusb | grep -i nvidia  # Should show 0955:7523

# 5. vhci_hcd loaded (for USB/IP)
lsmod | grep vhci_hcd

Execute Flash

# Windows Admin PowerShell — keep running:
usbipd bind --busid 1-1 --force
usbipd attach --wsl --busid 1-1 --auto-attach

# WSL2:
cd ~/jetson-flash/Linux_for_Tegra

sudo ./tools/kernel_flash/l4t_initrd_flash.sh \
    --external-device nvme0n1p1 \
    -c tools/kernel_flash/flash_l4t_external.xml \
    -p "-c bootloader/generic/cfg/flash_t234_qspi.xml" \
    --showlogs \
    --network usb0 \
    jetson-orin-nano-devkit internal

Expected Flash Output Timeline

~T+0:00   Step 1: Generate flash packages
~T+0:30   Reading ECID, fuses, EEPROM from device
~T+1:00   Generating signed bootloader images
~T+1:30   Making recovery ramdisk
~T+2:00   Making system.img (populating rootfs) ◄── SLOWEST STEP
~T+10:00  system.img complete
~T+10:30  Step 2: Generate RCM boot commandline
~T+11:00  rcmboot_blob generated
~T+11:30  Step 3: Start the flashing process
~T+12:00  RCM boot sent to device
~T+12:30  USB re-enumerates as RNDIS (0955:7035)
~T+13:00  usb0 interface appears ◄── THIS IS THE MOMENT OF TRUTH
~T+13:30  SSH connection established to Jetson initrd
~T+14:00  Writing QSPI partitions (BCT, MB1, firmware)
~T+18:00  "Flashing success"
~T+18:30  "Reboot device"

Success Output

[ 185]: l4t_flash_from_kernel: Successfully flash the qspi
[ 185]: l4t_flash_from_kernel: Flashing success
Flash is successful
Reboot device
Cleaning up...
Log is saved to Linux_for_Tegra/initrdlog/flash_1-1_0_20260225-095314.log

Post-Flash Verification

Remove Recovery Jumper

Remove the jumper wire between FC REC and GND. The Jetson will boot normally on next power cycle.

SSH to the Jetson

ssh nvidia@<jetson-ip>
# Password: nvidia

Verify the Installation

# OS version
cat /etc/nv_tegra_release
# R36 (release), REVISION: 4.0, GCID: 37537400, BOARD: generic

# Kernel
uname -a
# Linux jetson-orin 5.15.148-tegra #1 SMP PREEMPT ... aarch64

# Storage
df -h /
# /dev/nvme0n1p1  116G  7.0G  103G   7% /

# Memory
free -h
#                total   used   free
# Mem:           7.4Gi  1.1Gi  5.3Gi
# Swap:          3.7Gi     0B  3.7Gi

Troubleshooting Reference

Quick Diagnostic Commands

# Check if RNDIS module is loaded
lsmod | grep rndis_host

# Check USB devices
lsusb

# Check for USB network interfaces
ip link show | grep usb

# Check kernel messages for USB events
dmesg | grep -iE "usb|rndis" | tail -20

# Check if Jetson is in recovery mode (from Windows)
usbipd list  # Look for 0955:7523 (APX) or 0955:7035 (RNDIS)

# Check NFS server
systemctl status nfs-server

# Check flash logs
tail -f /tmp/flash_log.txt

Common Failure Modes

Symptom	Likely Cause	Fix
`Invalid target board`	Wrong target name for L4T version	Use `jetson-orin-nano-devkit` for R36.x
`gzip: kernel/Image: not in gzip format`	DSA keygen failure in recovery ramdisk	Patch `ota_make_recovery_img_dtb.sh`
`Waiting for target to boot-up... Timeout`	No RNDIS driver in WSL2 kernel	Build custom kernel with RNDIS
`Unknown symbol in module`	Vermagic mismatch or missing dependency	Run your own kernel + `modules_install`
`usbipd: error: Device is not shared`	Need admin privileges	Run `usbipd bind` in admin PowerShell
`There is no WSL 2 distribution running`	WSL2 not active when attaching USB	Start WSL first: `wsl -d Ubuntu -- sleep 999999`
`NFS server dependency failed`	`nfsd` module not loaded	`modprobe nfsd && systemctl start nfs-server`
`The operation was canceled by the user`	UAC prompt dismissed/blocked	Manually run commands in admin PowerShell

Quick Reference: Reflash Procedure

For subsequent flashes (assuming you kept the files):

# 1. Ensure .wslconfig points to custom kernel
#    C:\Users\<username>\.wslconfig should have:
#    [wsl2]
#    kernel=C:\\Users\\<username>\\wsl-kernel-rndis

# 2. Start WSL2
wsl -d Ubuntu -- bash -c 'sleep 999999' &

# 3. Load modules and start NFS (in WSL2 as root)
wsl -d Ubuntu -u root -- bash -c '
    modprobe rndis_host
    modprobe nfsd
    mount -t nfsd nfsd /proc/fs/nfsd 2>/dev/null
    systemctl start nfs-server
'

# 4. Put Jetson in recovery (FC REC jumper + power on)

# 5. Admin PowerShell:
usbipd bind --busid 1-1 --force
usbipd attach --wsl --busid 1-1 --auto-attach

# 6. Flash (in WSL2 as root):
wsl -d Ubuntu -u root -- bash -c '
    cd /home/<user>/jetson-flash/Linux_for_Tegra &&
    ./tools/kernel_flash/l4t_initrd_flash.sh \
        --external-device nvme0n1p1 \
        -c tools/kernel_flash/flash_l4t_external.xml \
        -p "-c bootloader/generic/cfg/flash_t234_qspi.xml" \
        --showlogs --network usb0 \
        jetson-orin-nano-devkit internal
'

Key Takeaways

Why This Is Hard

WSL2 is a VM, not bare metal. USB devices must be forwarded via USB/IP (usbipd-win), adding a layer of abstraction that NVIDIA's tools don't account for.
The WSL2 kernel is minimal. Microsoft strips out drivers that aren't typically needed in a VM, including USB network drivers like RNDIS. This is the single biggest blocker.
USB device re-enumeration. The Jetson changes its USB identity mid-flash (APX → RNDIS). Both usbipd auto-attach and the RNDIS kernel driver must handle this seamlessly.
Ubuntu 26.04 bleeding edge. Running a development distro means dealing with GCC 15 incompatibilities, removed DSA key support, and package naming changes.

What We Built

A custom WSL2 kernel (16MB bzImage) with USB RNDIS network support
A complete flash environment inside WSL2 with all NVIDIA dependencies
A repeatable procedure for flashing Jetson devices from Windows

Performance

Phase	Duration
Initial setup (downloads, extract, dependencies)	~45 min
Custom kernel build	~15 min
Flash execution	~18 min
Total first-time	~1.5 hours
Subsequent reflash	~20 min

Files to Preserve

Path	Size	Purpose
`~/jetson-flash/Linux_for_Tegra/`	~15GB	L4T BSP with rootfs and flash images
`~/wsl-kernel/`	~5GB (2GB after `make clean`)	Custom kernel source
`C:\Users\<user>\wsl-kernel-rndis`	16MB	Custom kernel bzImage
`C:\Users\<user>\.wslconfig`	<1KB	WSL2 kernel configuration

Appendix: Version Matrix

reComputer Model	Module	boardid	boardsku	L4T Target
J3010	Orin Nano 4GB	3767	0004	`jetson-orin-nano-devkit`
J3011	Orin Nano 8GB	3767	0003	`jetson-orin-nano-devkit`
J4011	Orin NX 8GB	3767	0001	`jetson-orin-nano-devkit`
J4012	Orin NX 16GB	3767	0000	`jetson-orin-nano-devkit`

All use the same target name — the flash tool auto-detects the module via EEPROM.

Document generated from a real flashing session on February 25, 2026. All commands were executed and verified.

slideep/JETSON_FLASH_WSL2_GUIDE.md

Flashing NVIDIA Jetson Orin Nano (reComputer J3011) from Windows Using WSL2

Table of Contents

Overview

The Challenge

The Solution (TL;DR)

Result

Hardware & Software Inventory

Hardware

Software

Architecture Overview

Data Flow During Initrd Flash

USB Device State Transitions During Flash

Phase 1: Environment Setup

Step 1.1: Verify WSL2

Step 1.2: Install usbipd-win

Step 1.3: Install Flash Dependencies in WSL2

Troubleshooting: Ubuntu 26.04 Quirks

Phase 2: Download & Prepare L4T BSP

Step 2.1: Download L4T R36.4.0

Step 2.2: Extract and Apply

Step 2.3: Configure Default User

Choosing the Correct Flash Target

Phase 3: Recovery Mode & USB Passthrough

Step 3.1: Enter Recovery Mode

Step 3.2: Verify APX Device on Windows

Step 3.3: Bind and Attach to WSL2

Step 3.4: Verify in WSL2

Phase 4: Flash Attempts & Troubleshooting

The Flash Command

Flash Process Steps (What the Script Does)

Issue 1: Invalid Target Board Name

Issue 2: ssh-keygen -t dsa Fails

Issue 3: "Waiting for target to boot-up..." Timeout

Issue 4: GCC 15 Incompatible with Kernel 6.6

Issue 5: Module Vermagic Mismatch (+ Suffix)

Issue 6: NFS Server Fails in WSL2

Phase 5: Building a Custom WSL2 Kernel with RNDIS Support

Step 5.1: Clone WSL2 Kernel Source

Step 5.2: Configure the Kernel

Step 5.3: Build the Kernel

Step 5.4: Install the Custom Kernel

Step 5.5: Verify and Load Modules

Module Dependency Chain

Phase 6: Successful Flash

Pre-Flight Checklist

Execute Flash

Expected Flash Output Timeline

Success Output

Post-Flash Verification

Remove Recovery Jumper

SSH to the Jetson

Verify the Installation

Troubleshooting Reference

Quick Diagnostic Commands

Common Failure Modes

Quick Reference: Reflash Procedure

Key Takeaways

Why This Is Hard

What We Built

Performance

Files to Preserve

Appendix: Version Matrix

Issue 5: Module Vermagic Mismatch (`+` Suffix)