1. Get Unlock-Code for the Bootloader:
https://emui.huawei.com/en/plugin.php?id=unlock&mod=unlock&action=apply
I could only succeed by Facebook login, otherwise I got the error message "No European Login" or something along these lines.
2. Install Fastboot:
http://forum.xda-developers.com/showthread.php?t=2317790
3. Activate developer options (tap 7x on Build-Nr under "Settings" -> "About phone"), under "Settings" -> "Devloper options" enable USB-Debugging.
4. Connect the phone to the computer and boot into Fastboot mode, either by
per console or by pressing "Vol-" and "Power" simultaneously. Confirm dialog on display.
5. With a Windows computer select "run" and enter:
Code:
fastboot oem-unlock 01234567891011 (replace with your code)
Confirm on screen. (Navigate with "Vol+/-" , confirm with "Power" button)
6. Your device will be reset.
7. Download and extract TWRP:
https://www.mega:#!FtB2gZKL!vEa351gkerd9EJC0nhJUHDb4jZKy4zlFdOMGMmucb2g
8. Once again boot into Fastboot mode, navigate to TWRP-folder and enter
Code:
fastboot flash recovery recovery_twrp.img
Wait for success message.
9. Enter
and shut down the phone again.
10. Download - do not extract - SuperSu:
http://download.chainfire.eu/supersu
(do not mind the beta, I tried the last stable version first, but if you update the app it will not succeed in updating the binary.)
11. Unplug USB cable, boot into TWRP with "Vol+" and "Power". You find the settings in the main menu on the second button from the bottom on the right side. There you tap on the world symbol and you can change the language to "English". Then you go back to the main menu, select "Advanced" and "ADB Sideload", connect the phone to the computer and enter
Code:
adb sideload path\to\BETA-SuperSU-v2.74-2-20160519174328.zip
If all goes well, your device is rooted and you can reboot the phone.
With Linux you can either begin each fastboot command with "sudo" or add your username to the group "androiddev":
http://android.stackexchange.com/questions/36954/fastboot-not-working-on-my-nexus-4/37085#37085
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So far I get error message
Code:
createTarFork( ) process ended with error: 255
when trying to backup the boot partition...