And this is regardless of dm-verity being disabled?
Yes, it is regardless!
I have dm-verity always off (not enabled in Magisk Manager) and I have also avb disabled in /vendor/etc/fstab.ext4.hi.... and fstab.f2fs.hi.... (I have different Huawei devices)
To make the issue clearer here is another summary:
I made a Rebrand Thread for Huawei P9-EVA here: https://forum.xda-developers.com/p9/development/rebrand-update-tool-hwota7-p9-eva-t3820849
The main reason for this is to allow users to unofficially update their device to Android 8 Oreo. Huawei has rolled out the Oreo OTA update in China, but has no plans to release this update outside of China. Although Oreo runs much better on the devices.
To make this possible, root is an important part, otherwise the mobile network will not work on the rebranded devices. Many users were very happy because they can now also use Oreo Treble Roms by the Open Kirin Team.
Okay → Devices rebranded to EVA-AL10 and updated to the official Oreo Firmware b528. With some modification everything is working fine.
→ Yesterday OTA Patch01 was available. I flashed the unmodified original Huawei ramdisk.img, uninstalled Magisk Manager and flashed the original EMUI Recovery. Then I agreed to the OTA update. The update was succesful installed.
After that I flashed the Magisk patched_ramdisk.img again, but the phone did not boot → it booted only with original b528 ramdisk.img
We were three people who tested it. Me and @dkionline
We tried everything that came to our mind. → flashing first original ramdisk and kernel.img and booted to system. Then flashing patched ramdisk.img b528 with Magisk 16, Magisk 16.7 with flag "force encryption" and without "force encryption" (related to - if device is with data encrypted or data decrypted)
Flashing TWRP was not a problem, and together with the original Huawei ramdisk.img phone was able to start to system. To get Root again, we must downgraded to b528 without this Patch.
→ The Patch includes a Fix for mms and Fix for gaming (changes a Line in a local.prop) and it includes also a Kernel patch.
Looking back, we should have tested a little more. What we did not test → making dd with TWRP from ramdisk.img after the OTA Patch and then patch the "dump" ramdisk.img with Magisk. → Maybe that would have worked - we do not know it now and I do not feel like reproducing it again. But perhaps @zgfg
can try this in a view days (he did not downgrade yet, because he is outside).
With this last test we could say it for sure, if the Kernel patch includes something to make Huawei Phones unbootable together with Magisk.
And coincidentally I read then in the Mate 10 forum that there also a user (with ALP-L29c636) got an OTA with a Patch01 and similar problem " I got a patch notification so I download it, rebooted and the patch installed (phone booted and I checked version and it was patch1
). Cool. So then I rooted using magisk and phone was soft bricked..." : https://forum.xda-developers.com/showpost.php?p=77405758&postcount=256
My first thought was simple, Huawei is now trying to prevent root with this patch01 and much confirms this theory....
→ Bootloader Unlock Site closed
→ TrustSpace is a new App in system which definitely check and disable Root (we had this app disabled and two of us has it deleted in system)
→ Downgrade with unofficial methods become danger for hardbrick, because of two different Xloader.img in the Firmware (Mate 10)