extract boot.img to root the tablet T8100 Allwinner A100

Search This thread

Zeh John

Member
Jun 28, 2022
16
0
@SamuEDL,

I'm preparing to flash LineageOS and while reviewing the procedure, I've noticed this on step 4:

fastboot flash system system-xxxx.img

I've seen no mention anywhere to downloading a system-xxxx.img file regarding LineageOS 17.1, neither here nor in the ROM's thread.

Did it escape me somehow, is this a mistake in the procedure that does not apply to LineageOS, or?...


Thanks.
 

SamuEDL

Senior Member
Aug 1, 2011
172
69
@SamuEDL,

I'm preparing to flash LineageOS and while reviewing the procedure, I've noticed this on step 4:



I've seen no mention anywhere to downloading a system-xxxx.img file regarding LineageOS 17.1, neither here nor in the ROM's thread.

Did it escape me somehow, is this a mistake in the procedure that does not apply to LineageOS, or?...


Thanks.
The system-xxx.img is the rom. In the case of LineageOS that I have given you, it is called "lineage-17.1-20210808-UNOFFICIAL-treble_a64_bvS.img" (The file that remains after decompressing).

About litegapps addons, I really don't know what they are for. Better check your page https://litegapps.github.io/documentation.html
 

Zeh John

Member
Jun 28, 2022
16
0
The system-xxx.img is the rom. In the case of LineageOS that I have given you, it is called "lineage-17.1-20210808-UNOFFICIAL-treble_a64_bvS.img" (The file that remains after decompressing).

About litegapps addons, I really don't know what they are for. Better check your page https://litegapps.github.io/documentation.html

Thanks for the hints!

I've checked the litegapps addons documentation and they only have procedures and instructions but not a definition...
I was going to write saying that so it must not be that important but I am actually now realizing that I've been having a lot of problems failing to install Gapps on LineageOS (all Recovery installations I've tried failed and only one suceeded with Magisk but it didn't have the Google Play Services and I couldn't login into my account) so that addon might actually be something...

I've been having a lot of failed experiences, specially with Magisk failing to root properly, but I'm going to read LineageOS' looooong thread for some eventual solution, if not I'll report back here.

Meanwhile, IF you're using LineageOS on this Allwinner, can you tell me if you've got it rooted and how you managed to do it properly, as well of what LiteGapps version you have?
I've really enjoyed the fluidity os LineageOS and I'd like to keep it if I could solve these 2 issues...

Thanks!
 

SamuEDL

Senior Member
Aug 1, 2011
172
69
Thanks for the hints!

I've checked the litegapps addons documentation and they only have procedures and instructions but not a definition...
I was going to write saying that so it must not be that important but I am actually now realizing that I've been having a lot of problems failing to install Gapps on LineageOS (all Recovery installations I've tried failed and only one suceeded with Magisk but it didn't have the Google Play Services and I couldn't login into my account) so that addon might actually be something...

I've been having a lot of failed experiences, specially with Magisk failing to root properly, but I'm going to read LineageOS' looooong thread for some eventual solution, if not I'll report back here.

Meanwhile, IF you're using LineageOS on this Allwinner, can you tell me if you've got it rooted and how you managed to do it properly, as well of what LiteGapps version you have?
I've really enjoyed the fluidity os LineageOS and I'd like to keep it if I could solve these 2 issues...

Thanks!

I have it rooted with magisk and use litegapps++ LTS. And I had no problem starting playstore.
 

Zeh John

Member
Jun 28, 2022
16
0
I have it rooted with magisk and use litegapps++ LTS. And I had no problem starting playstore.

I'm downloading litegapps++ LTS now and will start again from scratch with LineageOS after lunch.
Regarding Magisk and root, I'm just windering in my semi-noob thoughts if this failure to root properly could be somehow related with the Magisk .img boot image from the start of this post. But I'm assuming the installation procedure for LineageOS (and I am following it!) scraps everything in a nuke&pave fashion, so that Magisk boot image for the Stock ROM would be completely wiped and not interfere, right?
 

Zeh John

Member
Jun 28, 2022
16
0
@SamuEDL,

The good news first. I was able to install litegapps++ through Magisk and that one is solved. Thanks!

Now the bad news, there is definitely something wrong with my system because I can't install Magisk properly and root the tablet.
After installation, when opening the app, Magisk states it can't detect its su binary.
Titanium Backup can't access root but a very old app for finetuning the SD card's reading cache does work, asks for root permissions, writes its config and reads it upon reboot, keeping root access.
Root Checker also works perfectly and confirms root is working.
So Magisk isn't rooting properly.

I've tried different versions but it all ends up the same because it updates itself to the latest version and sometimes doesn't allow to attempt root when offline, and when I go online it disables rooting and instead asks for updating itself to the latest version.

I've uninstalled Magisk and it even gets weirder, to the point of not recognizing the internet connection when the browser confirms I'm online.
Or doesn't perform the usual automatic rooting and instead asks for a manual file, akin to this:


I've given it the boot.img you've supplied above in this thread and it works on it, but I realize it's output would be the same as what this does it taking a stock boot.img and get it Magisk patched to be installed with fastboot.
Either way, the practical end result is the same.

I've read something on the million tabs I had open about a missing symlink binding to to the su. I've downloaded a Magisk module to attempt fixing it but it aborted stating Magisk is not activated.

So this ends up in my previous post's questions about the boot.img, if LineageOS overwrites it with its own or what else. Googling around hasn't been helping much, I'm at a loss here... Should I install the stock ROM and start over, or?... Any help, please? Thanks, as usual!
 

DarcioManuel

Member
Jan 10, 2011
6
1
Hello again!
It is possible to use the short pin method to load a rom on this tablet?
I cannot start the tablet to enable debug mode. It crashes on startup and I have no access to anything other than the recovery menu, but I can't do anything other than reset, which has no effect!

Thanks
 

speedfreak007

Senior Member
May 12, 2010
353
36
As long as you don't install the fastboot drivers you won't be able to recover it. For this you will have to force the drivers. The device "USB Developer", uses this driver:

View attachment 5626577
I have installed the drivers + adb from the link in this thread, but "Google" doesn't show up in this screen. What am i doing wrong?

EDIT: i see in the last step of the adb + driver installer, the drivers get installed. This is however not working on my Windows 10 system (I don't get the driver installation UI). Can I find this manually?

My tablet is on the android with internals screen. Neither my mac can connect to it as my windows pc
 
Last edited:

Zeh John

Member
Jun 28, 2022
16
0
My tablet is on the android with internals screen. Neither my mac can connect to it as my windows pc
I can't help you with the Windows drivers cringe and neither with MacOS as I have 2 problems with Apple: A full brain and an empty wallet.

Worst chance, if you can't get those OSs to recognize your tablet, you can try a Linux live boot USB. This means downloading a Linux distro (I personally recommend Linux Mint), "install" the live boot on a USB thumb drive, and boot your computer from it. You will have a running OS without having to install it or mess with your existing installations.
Your device should be recognized out of the box and adb and an old version of fastboot are easily installable. This will be enough to give the fastboot continue command for your tablet to resume.

Quick caveats that pop into my mind:
1) The tablet will boot normally but might return to fastboot mode once restarted, so if you do this make sure it reboots properly before shutting Linux down. This happened to me and out of the box I can't remember how I got it to reboot normally.

2) This Linux OS will be running as a live session, meaning it has no persistence, so it won't save your files and settings once shut down or rebooted. Save all your files, notes and procedures taken elsewhere or you will lose them!

So if you can't unstuck yourself with Windows and MacOS and need guidance with this Linux procedure, let me know. Cheers.
 

SamuEDL

Senior Member
Aug 1, 2011
172
69
I have installed the drivers + adb from the link in this thread, but "Google" doesn't show up in this screen. What am i doing wrong?

EDIT: i see in the last step of the adb + driver installer, the drivers get installed. This is however not working on my Windows 10 system (I don't get the driver installation UI). Can I find this manually?

My tablet is on the android with internals screen. Neither my mac can connect to it as my windows pc
Did you have the bootloader unlocked? I'm telling you because if you didn't have it unlocked it won't help you recover your tablet.
Here you have a picture that explains how to install the drivers: https://forum.xda-developers.com/t/...0-allwinner-a100.4338541/page-2#post-86744087
 

Zeh John

Member
Jun 28, 2022
16
0
if you didn't have it unlocked it won't help you recover your tablet.
Not even to get the tablet out of a fastboot loop with the fastboot continue command? (assuming the OS is fine and has just been booted into fasboot mode and got stuck there like it has happened to me)
Just genuinely asking.
 

speedfreak007

Senior Member
May 12, 2010
353
36
I can't help you with the Windows drivers cringe and neither with MacOS as I have 2 problems with Apple: A full brain and an empty wallet.

Worst chance, if you can't get those OSs to recognize your tablet, you can try a Linux live boot USB. This means downloading a Linux distro (I personally recommend Linux Mint), "install" the live boot on a USB thumb drive, and boot your computer from it. You will have a running OS without having to install it or mess with your existing installations.
Your device should be recognized out of the box and adb and an old version of fastboot are easily installable. This will be enough to give the fastboot continue command for your tablet to resume.

Quick caveats that pop into my mind:
1) The tablet will boot normally but might return to fastboot mode once restarted, so if you do this make sure it reboots properly before shutting Linux down. This happened to me and out of the box I can't remember how I got it to reboot normally.

2) This Linux OS will be running as a live session, meaning it has no persistence, so it won't save your files and settings once shut down or rebooted. Save all your files, notes and procedures taken elsewhere or you will lose them!

So if you can't unstuck yourself with Windows and MacOS and need guidance with this Linux procedure, let me know. Cheers.
Thanks, I have retried it on another windows 10 machine and i could get my tablet to boot by doing fastboot continue. However, when I want to send the vbmeta, i get the following error: 'secure mode, fastboot limited used'.
EDIT: i forgot to do fastboot oem unlock
everything is working fine now. thank you very much for all your help
 
Last edited:
  • Like
Reactions: Zeh John

Romiz

New member
Jul 20, 2022
1
0
Good guys, I leave the boot.img for Tablet T8100 and patched with Magisk. Works correctly on the Rom Stock (Android 10 GO) on tablet T8100 with motherboard BND-A863-CV2.0.
[..]
Edit: I attached also the dump of the Rom Stock of my Tablet, in case someone needs it. https://www.mediafire.com/file/h0hnqhwah2qyf7y/RomStockT8100.zip/file
Only can be flashed by fastboot as a dump and only if you have an unlock bootloader.
@SamuEDL
Could you also post how did you manage to get the dump?
I'm struggling to get my own, because to make it with adb I need root permissions but to root the device I need the image of the boot partition (that I can not dump) and then patch it.
 

SamuEDL

Senior Member
Aug 1, 2011
172
69
@SamuEDL
Could you also post how did you manage to get the dump?
I'm struggling to get my own, because to make it with adb I need root permissions but to root the device I need the image of the boot partition (that I can not dump) and then patch it.
I did not do the dump, but an acquaintance. The dump is done through the UART port of the motherboard and guided by this guide: https://github.com/roleoroleo/yi-hack-Allwinner/wiki/Dump-your-backup-firmware-(serial-cable)
 

capitaoazevedo

New member
Jul 26, 2022
2
0
Hello everyone.
I managed to successfully install the rom but now I'm having a bit of a serious problem, the tablet even not being with any cable connected indicates that it is charging and gets quite hot, even if I try to turn it off he continues to indicate that it is charging. Anyone with this problem? thanks
 

Zeh John

Member
Jun 28, 2022
16
0
Hello everyone.
I managed to successfully install the rom but now I'm having a bit of a serious problem, the tablet even not being with any cable connected indicates that it is charging and gets quite hot, even if I try to turn it off he continues to indicate that it is charging. Anyone with this problem? thanks
Exactly which ROM did you install?
This post is about a modified boot image with root capabilities for the stock ROM. There might be some references to other ROMs but those might be just some a little offtrack references. (please correct me if I'm wrong!)
Or did you install just the boot image, keeping the stock ROM and you started having this behavior?

Could you please clarify?

I've never heard of such behavior, but I'm still noobish in this Android world.
But that definitely does not report as a normal behavior.

I could suggest you to "reinstall the ROM" (AKA repeat whatever you have done) to check if the symptoms persist or get solved, but before suggesting anything I believe it's better for you to clarify what you've installed first so we here can understand the situation better in order to be able to make better diagnostics and decisions.
Cheers, Capitão!
 

capitaoazevedo

New member
Jul 26, 2022
2
0
Exactly which ROM did you install?
This post is about a modified boot image with root capabilities for the stock ROM. There might be some references to other ROMs but those might be just some a little offtrack references. (please correct me if I'm wrong!)
Or did you install just the boot image, keeping the stock ROM and you started having this behavior?

Could you please clarify?

I've never heard of such behavior, but I'm still noobish in this Android world.
But that definitely does not report as a normal behavior.

I could suggest you to "reinstall the ROM" (AKA repeat whatever you have done) to check if the symptoms persist or get solved, but before suggesting anything I believe it's better for you to clarify what you've installed first so we here can understand the situation better in order to be able to make better diagnostics and decisions.
Cheers, Capitão!
Hey Zeh,

thanks for the reply, i installed the rom suggested by @SamuEDL (LineageOS) and followed all the steps as he described
 

Zeh John

Member
Jun 28, 2022
16
0
Hey Zeh,

thanks for the reply, i installed the rom suggested by @SamuEDL (LineageOS) and followed all the steps as he described
Thanks for the clarification, Capitão!
For what I know from what people are experiencing and reporting, the LineageOS versions of the Generic System Images Android versions 11 and 12 don't have the gyroscope working well, but the Android 10 version works all fine, that's what I currently have installed on my Lamentablet (I only report a half backed root, for some apps it works, for others they can't get root permissions but I can live with it).
And none of these report the problems you've been experiencing.
I can't give you specific troubleshooting but what I would do is, to save time, first try a Factory Reset and then reinstall the whole thing again if the Factory Reset fails to solve your problems. Remember to back up first!

I don't know if there are given checksums for those images so we can check the integrity of our downloads, or if they are checked when installing. You could have downloaded a problematic image file and that can do all sorts of unexpected behaviors. So if you reinstall again from scratch and keep on having weird and erratic behaviors, I recommend downloading the image file again.
 

SamuEDL

Senior Member
Aug 1, 2011
172
69
Hello everyone.
I managed to successfully install the rom but now I'm having a bit of a serious problem, the tablet even not being with any cable connected indicates that it is charging and gets quite hot, even if I try to turn it off he continues to indicate that it is charging. Anyone with this problem? thanks
I have never been notified of this error. Try to install the stock rom, if it persists it is a hardware problem and not a software one.
 

Top Liked Posts

  • There are no posts matching your filters.
  • 1
    I can't help you with the Windows drivers cringe and neither with MacOS as I have 2 problems with Apple: A full brain and an empty wallet.

    Worst chance, if you can't get those OSs to recognize your tablet, you can try a Linux live boot USB. This means downloading a Linux distro (I personally recommend Linux Mint), "install" the live boot on a USB thumb drive, and boot your computer from it. You will have a running OS without having to install it or mess with your existing installations.
    Your device should be recognized out of the box and adb and an old version of fastboot are easily installable. This will be enough to give the fastboot continue command for your tablet to resume.

    Quick caveats that pop into my mind:
    1) The tablet will boot normally but might return to fastboot mode once restarted, so if you do this make sure it reboots properly before shutting Linux down. This happened to me and out of the box I can't remember how I got it to reboot normally.

    2) This Linux OS will be running as a live session, meaning it has no persistence, so it won't save your files and settings once shut down or rebooted. Save all your files, notes and procedures taken elsewhere or you will lose them!

    So if you can't unstuck yourself with Windows and MacOS and need guidance with this Linux procedure, let me know. Cheers.
    Thanks, I have retried it on another windows 10 machine and i could get my tablet to boot by doing fastboot continue. However, when I want to send the vbmeta, i get the following error: 'secure mode, fastboot limited used'.
    EDIT: i forgot to do fastboot oem unlock
    everything is working fine now. thank you very much for all your help
    1
    Is there any special procedure, configuration, etc. should one need to install the stock ROM, or the procedure to install other ROMs apply here too?

    Also, would installing the stock ROM overwrite the Magisk rooted boot image and also relock the boot loader?
    Here: https://forum.xda-developers.com/t/...t-t8100-allwinner-a100.4338541/#post-86499627

    Overwrites boot, but does not lock bootloader.
  • 2
    Do you use any custom boot or/and vendor image? i allready tried a few of the roms on that page and i always end up with a boot loop. The ones i used are based on ARM or A64, did chose the right ones?
    Can you give me some intructions on how to install it properly in order to boot?
    Is there any Twrp or any similar funcional custom recovery for this device ?

    Thank you in advance
    I use the boot modified with Magisk and roms GSI arm32_binder64-ab (pphusson) / a64_bvS (LineageOS).
    P.D: In roms superior to Android 10, the gyrosensor does not work.

    Instructions:
    0. Get an up-to-date fastboot on your computer (fastboot —version should give version >= 29)
    1. Get vbmeta.img from https://dl.google.com/developers/android/qt/images/gsi/vbmeta.img and get product_gsi.img from https://forum.xda-developers.com/t/tutorial-magisk-on-gsi-on-devices-with-dynamic-partition.4311045/
    2. From running Android, do adb reboot bootloader
    3. When you start the bootloader, enter the following commands
    fastboot --disable-verity --disable-verification flash vbmeta vbmeta.img
    fastboot reboot fastboot
    4. When you see the Recovery fastbootd, enter the following commands
    fastboot delete-logical-partition product
    fastboot delete-logical-partition product_a
    fastboot delete-logical-partition product_b
    fastboot flash system system-xxxx.img
    fastboot create-logical-partition product 400000000
    fastboot flash product product_gsi.img
    5. Finally, move with the volume buttons to "Enter recovery". Then a "wipe data/cache" and confirms.
    6. Reboot and enjoy
    2
    But to use fastboot i have to pass those files to the sd card or i have to connect the tablet to the computer ?
    If it is necessary what program do I use to install the software ?
    Do I need to use the bios ?
    Thanks !
    You have to connect it to the PC, but possibly you can not do much with the blocked bootloader.
    PD: To put the tablet in fastboot mode press VOL - and POWER. To know if it is in FastBoot mode, there will be an image of an Android.

    Instructions
    1. Download the ADB / FastBoot Tool (https://developer.android.com/studio/releases/platform-tools#downloads)
    2. Unzip it next to the backup files
    3. Opens a cmd and introduce the following commands:
    fastboot flash super super.img
    fastboot flash boot boot.img
    fastboot flash recovery recovery.img
    fastboot -w
    fastboot continue
    4. Done.





    ------------------------------------------
    By the way you guys, I tried to introduce the ROM from the Q-Link Scepter 8 tablet at the T8100. But without success, Phoenix (Pro and Suit) is blocked and not flash. Even though the motherboard were similar. A pity, it would have been fine to join communities.
    1
    Hello !

    A lot of people like me got this 'gift' tablet (in Spanish, we call it "the lamentablet", because it is "lamentable" = "terrible"):

    https://www.the-china-office.com/t8100-tablet (here you can see full specifications)

    That b***c allows us to unlock its bootloader, but in order to root it, we need to have the boot.img to apply magisk on it.

    But the thing is that we cannot obtain it, nor dump the firmware, just in case... So, we are stuck.

    Also in the docs on that webpage, it's a mention to a link with the firmware, but it is not available.

    There is also no OTA update to play with...

    Is there any way to obtain that boot.img / get all the partitions ? I've tested to make an adb shell to make commands to dump the partitions, but it says "it's closed", so not allowed.

    I've tried to find a TWRP version but hey, guess it... There is none.

    So, ... Got any ideas, you... GREAT "TECH GURUS" ?

    Thanks in advance !
    1
    I have the same tablet, and would like to know if anyone has made some progress on this. As for now it's an useless piece of ****. Would like to play around with it, I can think of a couple uses for it. Thanks
    1
    Did you get this worked out? If not, you made reference to an OTA update file. If you have the OTA update.zip, upload it to Google Drive or other file host and post a download link. I should be able to extract the boot.img and recovery.img from the update archive. (If your tablet has a boot image devoid of a ramdisk, you will need to root using the ramdisk from the recovery.img). To determine ramdisk status, install the latest Magsk app on your tablet. Open the app and look for "Ramdisk" in the top section of items listed. If you see a "Yes," standard boot.img patching will work. If it indicates a "No," you'll need a recovery.img.