jetpack-flash-wsl2

name	jetpack-flash-wsl2
description	Flash JetPack on Jetson from Windows using WSL2 + usbipd-win. Covers custom WSL kernel setup, USB passthrough, and Seeed BSP massflash. Not officially supported — use native Ubuntu if issues persist.

Flash JetPack with WSL2

Stability warning: This is not an officially supported flashing path. Seeed documents it as a workaround. If you hit repeated USB or flash failures, switch to a native Ubuntu 20.04/22.04 machine.

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Execution model

Run one phase at a time. After each phase:

• Relay all command output to the user.
• If output contains [STOP] → stop immediately, consult the failure decision tree below.
• If output ends with [OK] → tell the user "Phase N complete" and proceed to the next phase.

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Prerequisites

Requirement	Minimum
Windows	10 build 1903+ or Windows 11
WSL2	installed and enabled
usbipd-win	v4.x+
JetPack / WSL distro	JP4.x → Ubuntu 18.04 · JP5.x → 18.04 or 20.04 · JP6.x → 20.04 or 22.04

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Phase 1 — Check system (PowerShell)

Verify Windows build, WSL version, and usbipd-win. Install the target Ubuntu distro if missing.

reg query "HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion" /v CurrentBuild
wsl -v
usbipd --version
wsl --install -d Ubuntu-22.04

Expected: build ≥ 19041, WSL 2.x, usbipd 4.x. [OK] when all three pass.

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Phase 2 — Set up custom WSL2 kernel (PowerShell + WSL)

The stock WSL2 kernel lacks USB RNDIS support required for flashing. A pre-built kernel is needed.

1. Download the pre-built kernel from the Seeed OneDrive link (see references/source.body.md). SHA256: f249022feab9372d448d236a4401e087d0f150dd6b3367b571f0b9a703bd2d38
2. Place it at D:\WSL_Kernel\bzImage (or any path without spaces).
3. Edit %USERPROFILE%\.wslconfig — add or update the [wsl2] section:

   [wsl2]
   kernel=D:\\WSL_Kernel\\bzImage
   

4. Restart WSL and verify:

wsl --shutdown

# In WSL after restart:
uname -a
zcat /proc/config.gz | grep RNDIS

Expected: uname -a shows the custom kernel tag; grep RNDIS returns CONFIG_USB_NET_RNDIS_HOST=y. [OK] when both pass.

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Phase 3 — Enter force recovery mode on Jetson

Physical steps — no commands. Do these in order:

1. Power off the Jetson device completely.
2. Short the FEC and GND pins with a jumper.
3. Connect the USB-C cable from the Jetson to the Windows host.
4. Connect power to the Jetson; wait 2–3 seconds, then remove the jumper.

The device is now in APX (force recovery) mode. Proceed immediately to Phase 4.

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Phase 4 — Attach USB device to WSL (PowerShell as Administrator)

usbipd list
# Locate the "NVIDIA APX" entry and note its bus ID, e.g. 1-1
usbipd bind -b 1-1 -f
usbipd attach -b 1-1 --wsl --auto-attach

Verify in WSL:

lsusb
# Expected line: Bus 001 Device 00x: ID 0955:7045 NVIDIA Corp. APX

[OK] when lsusb shows the NVIDIA APX device. [STOP] if it does not appear — see failure decision tree.

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Phase 5 — Flash (WSL terminal)

Replace <user> and <xxxx> with your actual values.

# Install flash prerequisites
sudo apt install -y qemu-user-static sshpass abootimg nfs-kernel-server libxml2-utils binutils

# Move image from Windows Downloads into WSL home
mv /mnt/c/Users/<user>/Downloads/mfi_recomputer-<xxxx>.tar.gz ~

# Remove accidental execute bit, then verify checksum
chmod -x ~/mfi_recomputer-<xxxx>.tar.gz
sha256sum ~/mfi_recomputer-<xxxx>.tar.gz

# Extract
tar -xzf ~/mfi_recomputer-<xxxx>.tar.gz
cd mfi_recomputer-<xxxx>

# Flash via Seeed BSP massflash
sudo ./tools/kernel_flash/l4t_initrd_flash.sh \
  --flash-only --massflash 1 --network usb0 --showlogs

Expected: flash log ends with Flash success. [OK] when the device reboots into JetPack. [STOP] on any error — see failure decision tree.

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Failure decision tree

Symptom	Action
APX device not visible in usbipd list	Confirm device is in force recovery mode (redo Phase 3). Try a different USB port. Disable Windows Firewall temporarily.
usbipd attach succeeds but lsusb in WSL shows nothing	Confirm usbipd-win is v4.x+. Rerun usbipd attach. Check that the correct WSL distro is targeted.
RNDIS not in kernel config	Custom kernel not loaded. Verify .wslconfig path has double backslashes. Run wsl --shutdown and retry.
Flash times out or stalls	Cable quality issue — use a cable ≤1.5 m. Ensure 5 V / 4 A power supply. Consider switching to native Ubuntu.
Permission denied on /dev/bus/usb	Run sudo chmod 666 /dev/bus/usb/001/* in WSL, then retry flash.
usbipd bind fails	Run PowerShell as Administrator.
SHA256 mismatch on image	Re-download the BSP image. Do not flash a corrupt image.
Repeated unexplained failures	This method is not officially supported. Switch to a native Ubuntu 20.04/22.04 host.

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Reference files

• references/source.body.md — full original Seeed tutorial with screenshots, kernel download link, and additional context (reference only)