[Huawei P8 Guides, News, & Discussion] Tecalote:
Hello and welcome,

There are so many different Firmware versions related to cust (yours is c636 and you have latest Firmware b372 from 2017-06-14 /88000 or 87994)

I guess you can Root with latest SuperSU 2.82 SR5.

Dont use the old Root method from OP - it dont work properly on newer Firmwares.

I would do it with following steps, beginning from step 1.

You have no Root - that's why you start with step one.

But all the other Users, which have already Root with older versions of SuperSU - since SuperSU 2.82 it is required to UNROOT your device before flashing SuperSU 2.82 xxx

DON'T FLASH NEW SUPERSU OVER EXISTING ROOT!

Make Unroot directly from SuperSU App on Homescreen - SuperSU asking you for restoring Stock boot.img twice - say yes!

Phone reboot automatically and restore original boot.img.

If it works, start with step 6

If it doesn't work - don't flash new SuperSU.

In this case you must flash first UNSU Script (linked in OP) after don't boot to the system but restore immediately original Stock boot.img from TWRP Backup (or download the Firmware and extract it from update.app with Huawei Extractor and flash it with adb in fastboot mode or flash it with TWRP to: boot by choosing img)

After you can flash SuperSU

Following steps are described for Phones without Root over original unmodified Firmware:

1) Enable Developer Options and inside USB Debugging (settings /about phone - 7x klick on build number)

2) Your Bootloader must be open - if not you must receive Unlock-Code from Huawei (this information you can find in OP and you can search the Thred for it)

3) Flash newest TWRP: [url]https://eu.dl.twrp.me/grace/twrp-3.1.1-0-grace.img.html[/URL]

4) Soon as TWRP is flashed, disconnect USB Cable from Device and boot to TWRP with VOL+ and Powerbutton (dont restart to system cause twrp will be overwritten then)

5) Set up in settings of TWRP time zone, language...

6) In main menu go to Backup and SELECT STORAGE (Micro-SD) - Choose following partitions to backup: boot - cust - data - system (if Root failed - you must restore boot.img from this Backup)

7) Root with following SuperSU - its modified by myself (enables init.d and SELpermissive) SuperSU-v2.82-SR5-permissive.zip

- I have tested on P8 GRA-L09 b399: [url]https://www.androidfilehost.com/?fid=962187416754458671[/URL]

Just flash it with TWRP - you dont need to enter any command in Terminal - it will root systemless by default (except you had before Root in system, but on unmodified stock boot.img it will root systemless).

Reboot phone after flashing SuperSU without wipe of Dalvik/Cache!

Phone boot up twice (first boot goes canceld, but second boot arrive system) - and you will find on a blank site of your homescreen the SuperSU App.

No you have Root!

But it is recommended, after flashing BusyBox with TWRP (which enables more features of Root): Busybox YDS by YashdSaraf: [url]https://xdaforums.com/android/software-hacking/tool-busybox-flashable-archs-t3348543[/URL]

- use for P8 in download section Busybox-xxx-YDS-ARM.zip (it contains x64)

or alternative you can Busybox by osmOsis (universal architecture): [url]https://xdaforums.com/attachment.php?attachmentid=4410553&d=1517852861[/URL]

Tell me your result :)