To root your device using a 907 patched boot image, you typically need to match the file exactly to your specific firmware version (often associated with OxygenOS 11.2.9.9 for the OnePlus 9 series). While some users look for pre-patched files, the safest and most reliable way to get a "full" patched boot image is to create it yourself using the Magisk App.
Rooting an Android device with Magisk by downloading a pre-patched "907" boot image is highly risky. Magisk experts and official documentation strongly recommend that users patch their own device's stock boot image rather than downloading one from an external source to avoid "bricking" the device due to mismatched build numbers. Risks of Downloading Pre-Patched Images
Security Hazards: Pre-patched images from unofficial sources could contain malware or unauthorized modifications. download 907 patched boot image for magisk full
Best Practices:
This temporarily boots the patched image. If your phone starts normally, Magisk will appear as “installed” but temporarily. Reboot and it’s gone. This is a safe test. To root your device using a 907 patched
ADB & Fastboot: Download the latest Android SDK Platform Tools on your PC.
Using a patched boot image from a different device or firmware version will result in a bootloop (your phone gets stuck on the logo screen). If your phone starts normally, Magisk will appear
Transfer the patched image to a computer with ADB and Fastboot installed. Reboot your phone into Fastboot mode. Use the command: fastboot flash boot [filename].img. Resource Links Official Guide: Magisk Installation Documentation