[OnePlus 6 ROMs, Kernels, Recoveries, & Other Devel] dragos281993:
Ok, so after reading through most of the comment, I was almost not gonna try this kernel myself, f2fs too. But after making some backups and transferring them to my laptop I decided I'd give it a shot. It's software, so it's easily fixable in case something goes wrong.

Yes, it's true that there are basically no instructions regarding the correct procedure on how to get this going, so [MENTION=4898097]arter97[/MENTION], bro, some steps on 'how to do it' for the less experienced folk, wouldn't hurt at all.

But if you think it through for a second, you'll realize it's pretty logical what to flash first (etc), so that automatically makes it a relatively easy procedure. So, I'll just write down the steps to properly boot your phone up with this kernel & data formatted to f2fs. I'll write the steps with sub-steps if it requires more info at specific parts.

How it's done (I hope you know your way around "fastboot"):

Back up your data before anything cause the internal storage will get "epilated".

* The phone will not be encrypted after this.

* The phone gets stuck in a bootloop if you're trying the kernel with /data on ext4. Probably something arter missed when putting it together.

1. Reboot to bootloader.

2. Flash the 9.0.3_stock_boot.img so the stock recovery can be installed:

* fastboot flash boot oos_9.0.3_stock_boot.img (the boot.img name coincides with the file I linked above)

3. Now reboot to stock recovery.

4. Go to "Wipe data and cache", tap on "Reset system settings" and choose "Yes".

* this way you make sure the stock recovery performs a clean factory reset without screwing anything up somehow. I like to be safe this way.

5. After that, reboot to bootloader straight from the stock recovery.

6. Boot into twrp:

* fastboot boot twrp.img (replace "twrp" with however your twrp file is called).

** I used "blu_spark_v9.91". Not sure if it's the latest version, but I was too lazy to look it up so I used that one.

7. Once booted into twrp go ahead and copy "f2fs_format.zip" to /sdcard (the internal storage, main folder or whatever you want to call it).

* we're now about to format /data to f2fs.

8. Flash the file you just copied.

* you'll most likely get an error, but don't panic. It does that because it needs to unmount the /data partition.

* navigate to root ("/") by just tapping on "Up a level" when you're in the main section of the internal storage.

* you'll find here a copy of "f2fs_format.zip", so flash that.

* it'll go through nicely now.

9. After that, reboot to bootloader.

10. Boot into twrp again using step 6.

11. Copy arter's kernel to the internal storage and flash it.

12. Reboot to system.

* it took 2-3 minutes for my phone to boot up.

13. After you got to the device setup part, just reboot to bootloader.

14. Boot into twrp following step 6 again.

15. Copy blu_spark.zip to the internal storage and flash it (again, I personally used bluspark.v9.91).

16. Reboot into twrp to see if it got installed.

17. Then reboot to system and set up your device.

18. After it's done, reboot into twrp and flash Magisk, then reboot to system, of course.

Note that the kernel is pretty much stock in terms of features. It's just got a lot of patches and f2fs so that should make it superior to the stock one. It's not exactly noticeable though, so I don't know if it's totally worth it though, although you're gonna be the one to decide in the end. As for me, I'd rather stay on the default filesystem in case I want to try other kernels which may not have f2fs support.

Anyway, I hope I didn't miss anything.

The main point here is that this kernel works well, unless I haven't got into the right corners where bugs tend to hide, but if you follow the steps above without skipping a single thing, you can try it and see for yourself how stable this thing actually is.