CHUWI Hi9 Air 64GB MT6797 X20 Deca Core 10.1 Inch 2K Screen Android 8 Dual 4G Tablet

[ULAMSS5]

1. If you format with SPFT and don't have IMEI backup you'll lose all the keys of your device. Make a backup first. After flashing stock, unlock bootloader, flash twrp.
3. No. You need to restore data to vendor partition after you deleted it's data, this is where all the drivers are. Para is a partition that holds a flag that will prevent booting even on a working system after a bootloop. You need to restore it to be able to boot.
4. You don't need permissiver, but of course you need to flash disable verity and optional encrypt, encryption is not supported in TWRP and GSI's and verity needs to be disabled to be able to boot any custom ROM.

Thanks! Feels like it's all coming together.

Two last questions: "If you format with SPFT and don't have IMEI backup you'll lose all the keys of your device."

1. is this a different back up than the vendor/para back up to be done in twrp?
2. what "keys" are you referring to?

Because I've already semi-bricked my device many times, each time I just flash back to OEM with SPFT and it works. Should I be worried about this?

 

[thecoolkid]

Thanks! Feels like it's all coming together.

Two last questions: "If you format with SPFT and don't have IMEI backup you'll lose all the keys of your device."

1. is this a different back up than the vendor/para back up to be done in twrp?
2. what "keys" are you referring to?

Because I've already semi-bricked my device many times, each time I just flash back to OEM with SPFT and it works. Should I be worried about this?

I'm taking about all partitions that aren't flashed in SPFT because they are device specific like IMEI and DRM keys. It's a different backup, use my tool for that.

 

[ULAMSS5]

I still need help mate, it refuses to boot to anywhere but TWRP.

The detailed steps I've done:

1. SPFT back to OEM,
2. Boot in to enable OEM unlock, USB Debugging,
3. Boot into Fastboot Mode (shut down, then hold Power + Vol Up, select Fastboot mode)
4. Open CMD, `fastboot oem unlock`, back to tablet, Vol Up for yes.
5. `fastboot flash recovery recovery.img`
6. `fastboot reboot recovery`

7. Wait for reboot into TWRP

Cancel any prompts for password, Swipe to allow modifications​

8. Run backup.bat
9. TWRP > Mount > Uncheck Cache
10. Run setup_parted.bat

unit MiB​

print​

rm 28​

rm 29​

rm 30​

rm 31​

mkpart vendor ext4 240 740​

name 28 vendor​

set 28 msftdata on​

mkpart system ext4 740 4836​

name 29 system​

set 29 msftdata on​

mkpart cache ext4 4836 4936​

name 30 cache​

set 30 msftdata on​

mkpart userdata ext4 4936 100%​

name 31 userdata​

set 30 msftdata on​

quit​

y​

8. Run restore.bat
9. Copy PixelExperience_Plus_arm64-aonly-11.0-20211011-UNOFFICIAL.img & no-verity-opt-encrypt-6.1.zip to onboard SD
10. Flash PixelExperience_Plus_arm64-aonly-11.0-20211011-UNOFFICIAL.img to "System Image"
11. TWRP Prompts Reboot but also warns "No system image detected!"

Attempt reboot, no luck, goes back into TWRP.​

Flash the PE Plus image again. No warning this time, just​

[IMAGE FLASH COMPLETED]​

12. Reboot

Select Do Not Install when prompted by TWRP to install TWRP App​

no luck, goes back into TWRP​

13. Reboot

Agree to install TWRP App​

no luck, goes back into TWRP​

13. Attempt to flash "no-verity-opt-encrypt-6.1.zip"
Error: Unable to find boot block location!

- Aborting...​

Failed to patch boot image!​

Updater process ended with ERROR: 1​

Error installing zip file '/sdcard/no-verity-opt-encrypt-6.1.zip'​

no luck, goes back into TWRP​

What am I doing wrong?

 

[thecoolkid]

I still need help mate, it refuses to boot to anywhere but TWRP.

The detailed steps I've done:


What am I doing wrong?

set 31 msftdata on

Remember to format partitions after you create them (use the prompt after you quit parted and select yes)

8. You don't have to restore now. It's for when you wipe whole memory block in SPFT only.

Also flash disable verity, force encrypt.

Also mount system in twrp and make sure there are files in /system. And make also sure there isn't a "system" folder inside /system. Otherwise the image is broken or system-as-root...

PS: my repartitioning tool should be ready in about two weeks I'm out of town now, but it's almost ready. Stay tuned for more info

 

[ULAMSS5]

set 31 msftdata on

OMG thank you! Can't believe I missed that....

Also flash disable verity, force encrypt.

Do you mind sharing where to get this? The ones I can find are all "no-verity-opt-encrypt", which give the error quoted above.

 

[thecoolkid]

OMG thank you! Can't believe I missed that....


Do you mind sharing where to get this? The ones I can find are all "no-verity-opt-encrypt", which give the error quoted above. I also found this which doesn't appear to work. It flashes but at the end gives an error about not being able to find/mount /nvdata, which is probably for other devices since it's /NvData on the Chuwi Hi9Air

Zackptg5 - Android

zackptg5.com

Edit: I almost forgot. My backup tool backs up boot, so if your IMEI and the rest are ok, make a backup after you flash dm verity force encrypt disabler, bc when you restore stock boot you will have to flash it again. Or just comment out boot partition from restore.bat

 

[ULAMSS5]

Zackptg5 - Android

zackptg5.com

I found that too, it flashes but at the end gives an error about not being able to find/mount /nvdata, which is probably for other devices since it's /NvData on the Chuwi Hi9Air. After the flash, I can't even manually mount /NvData anymore, which is possible before the flash or after a reboot.

 

[thecoolkid]

I found that too, it flashes but at the end gives an error about not being able to find/mount /nvdata, which is probably for other devices since it's /NvData on the Chuwi Hi9Air. After the flash, I can't even manually mount /NvData anymore, which is possible before the flash or after a reboot.

It's not important, works for me with that error. If you like you can restore nvdata from your backup manually

 

[ULAMSS5]

It's not important, works for me with that error. If you like you can restore nvdata from your backup manually

So it boots for you despite that error? That means my mistake lies elsewhere?

 

[thecoolkid]

So it boots for you despite that error? That means my mistake lies elsewhere?

Most probably. Yes, I have no problems.
Try to boot phh aosp first to troubleshoot.

 

[ULAMSS5]

Most probably. Yes, I have no problems.
Try to boot phh aosp first to troubleshoot.

is "phh aosp" a different ROM?

Will I need to restore to OEM with SPFT and re-do all the partitioning stuff?

 

[thecoolkid]

is "phh aosp" a different ROM?

Yes. It's the base that all other phh gsi's are based on:

Release AOSP 11.0 v313 · phhusson/treble_experimentations

October security patch 313 bootanimation! Probably latest AOSP 11 build, unless I get super motivated

github.com

Will I need to restore to OEM with SPFT and re-do all the partitioning stuff?

No. Just flash to system and boot.

 

[ULAMSS5]

Yes. It's the base that all other phh gsi's are based on:

Release AOSP 11.0 v313 · phhusson/treble_experimentations

October security patch 313 bootanimation! Probably latest AOSP 11 build, unless I get super motivated

github.com

No. Just flash to system and boot.

I tried it as well, same. Either with or without disable verity, it always boots back to TWRP.

Also, for what it's worth, I did a naive patch of that disable verity, simply replaced all "nvdata" with "NvData", and the error I was getting no longer appears.

Still, doesn't help me boot to system though (with either phh or PE ROMs)

 

[thecoolkid]

I tried it as well, same. Either with or without disable verity, it always boots back to TWRP.

Also, for what it's worth, I did a naive patch of that disable verity, simply replaced all "nvdata" with "NvData", and the error I was getting no longer appears.

Still, doesn't help me boot to system though (with either phh or PE ROMs)

As a last resort try restoring "para" partition, it holds a flag for unsuccessful boot. You should have a backup of it from the time your system was booting (either gsi or stock).

 

[thecoolkid]

I tried it as well, same. Either with or without disable verity, it always boots back to TWRP.

Also, for what it's worth, I did a naive patch of that disable verity, simply replaced all "nvdata" with "NvData", and the error I was getting no longer appears.

Still, doesn't help me boot to system though (with either phh or PE ROMs)

One more thing... You did remember to restore vendor partition after you formatted it? Kek it'd be funny if you didn't

 

[ULAMSS5]

Simply running your "restore.bat" tool should cover both "para" and "vendor", right? I tried that, and without flashing anything else, attempted a reboot to system, which fails. Only boots to TWRP even with a full restore.

From this point, neither phh nor PE (+ disable verity) boots to system, either.

 

[thecoolkid]

Simply running your "restore.bat" tool should cover both "para" and "vendor", right? I tried that, and without flashing anything else, attempted a reboot to system, which fails. Only boots to TWRP even with a full restore.

From this point, neither phh nor PE (+ disable verity) boots to system, either.

No? If you read my tips I said to make a TWRP backup of Vendor, Para, System and Boot. My tool only makes a backup of partitions that can't be backed up in TWRP and can't be flashed in SPFT aka. device specific partitions (+BOOT bc it's small). You need to manually backup and restore vendor. If you're resizing vendor partition to smaller size, you need to make a compressed file backup of Vendor, bc original image might not fit. Try to flash stock vendor.img and boot.img in TWRP. Then again verity disabler.

YOU WON'T BE ABLE TO BOOT ANY ROM WITHOUT VENDOR, NOT EVEN STOCK

 

[GreZord]

I'd recommend you to test the newer Android 11 GSIs, especially the eternityson's ones, since they have an inbuilt option to pass SafetyNet, checking "SafetyNet" and "Spoof Pixel 5" in Phh Treble Settings -> Misc Features. With this feature, you should be able to use all apps in Play Store (I'm used to use NikGapps).

Only be sure you've flashed dm-verity and force encrypt disabler before booting to the GSI for the first time. Probably the issue you faced in v300l is related to the encryption (which is partially broken in A11 for some MTK devices including ours).

For me, the best GSI at this moment is Bless, the battery life is stunning and the only bug I've found is the upside-down front camera (what's a common issue since the latest A10 GSIs). I didn't notice any screen issue, however, I always use low brightness. Btw can you explain this screen issue, please?

Thank you for your activity! So, in terms of battery consumption, is Bless better or at least the same as stock? Or should I try to repartition device for PixelExperience to achieve even better performance/battery ratio? I've got a special 128 Gb model of Chuwi Hi9 Air and certain earlier experiments with Android 9 based GSI firmwares were quite troublesome. Even my older Sony Xperia and newer Xiaomi Redmi Note phones were easier to restore after boot loop.

 

[santosst]

Thank you for your activity! So, in terms of battery consumption, is Bless better or at least the same as stock? Or should I try to repartition device for PixelExperience to achieve even better performance/battery ratio? I've got a special 128 Gb model of Chuwi Hi9 Air and certain earlier experiments with Android 9 based GSI firmwares were quite troublesome. Even my older Sony Xperia and newer Xiaomi Redmi Note phones were easier to restore after boot loop.

Wow, 128 GB is nice!
Well, in my opinion, Bless + NikGapps had better battery consumption than stock, but it may vary according to your use. However, Bless A11 didn't receive updates since May, so I migrated to OctaviOS + BitGapps (with their SafetyNet fix). The battery life isn't as good as with Bless but it's ok for me.

About boot loops, in theory, flashing stock with SP Flash Tool is the best way to recover the device, but other ways are also good. For example, formatting data plus flashing stock system.img should be enough if you didn't modify the boot partition (like using Magisk). If the device is rebooting to recovery, you can use thecoolkid's tool to restore the para partition.

 

[ULAMSS5]

Vendor, Para, System and Boot

No? If you read my tips I said to make a TWRP backup of Vendor, Para, System and Boot. My tool only makes a backup of partitions that can't be backed up in TWRP and can't be flashed in SPFT aka. device specific partitions (+BOOT bc it's small). You need to manually backup and restore vendor. If you're resizing vendor partition to smaller size, you need to make a compressed file backup of Vendor, bc original image might not fit. Try to flash stock vendor.img and boot.img in TWRP. Then again verity disabler.

YOU WON'T BE ABLE TO BOOT ANY ROM WITHOUT VENDOR, NOT EVEN STOCK

Thanks for your help, but this still does not work. Still only boots to TWRP.

I also realized that once I flash TWRP, and nothing else, it's already not possible to book back to system, even if the system is the stock ROM from SPFT. Is there something wrong with this TWRP?