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[Guide]Alcatel Idol 5 6060C Bootloader Unlock and TWRP[/Guide]

New From A-TEAM: lehmancurtis147​
ALCATEL IDOL 5 : 6060C​ACCESS FASTBOOT
UNLOCK BOOTLOADER
INSTALL TWRP
Special thanks to the mVirus Team for the reboot tool.
Ok, here we go!!!
Start fastboot:
1.*Unpack and launch the boot mode tool.
2.*Power off your 6060C.
3.*While holding vol- plug in device to PC.
4.*While continuing to hold vol- press power until the device starts and release power (not vol-).
5.*Once you see fastboot at the bottom of the device you can release vol-.
Unlock Bootloader:
Now that you are in fastboot mode, we need to unlock the bootloader.
Code:
fastboot oem unlock
Install Custom Recovery:
I forgot to mention I also built a working TWRP.img for this device.
1.*Unzip the recovery.zip.
2.*To install it.
Code:
fastboot flash recovery recovery.img
3.*then...
Code:
fastboot oem reboot-recovery
4.*Welcome to team win recovery!
DOWNLOADS:
This is the boot-mode tool:
https://androidforums.com/attachments/mtk-bootmode-tool-zip.153347/
twrp link:
https://drive.google.com/file/d/1teI23ASm2IbIy_r4xV0jlzz_TzS3cvTc/view?usp=sharing
NOTE:
Unless you remove verity (and a handful of other annonyances) you will loose twrp. Luckily, I've already built a replacement system.img to solve this. Once its working right I'll share it.
I have the system image working, but it's huge. Probably why system and vendor were split in android 8. It's a 4.6 gigabyte image so as soon as I decide the best way to host it I will post it.
In the mean time, the way to keep updated is our telegram group.
A-Team General Discussion
Anything Alcatel, AIO ToolKit, Android, CricketRom
https://t.me/Android_General_Chat

Recoveries
!!!ANNOUNCEMENT!!!
New Recovery Options Available​
I now have managed to build a fully functional Pitch Black Recovery Image and and Orange Fox Recovery Image (the later is built from mostly 9.0 branch) and will be making them available soon if I see that anyone is actually interested.

The recovery image files are compiled from source and not a Frankenstein type. So I can address any recovery issues (within the scope of reason).

Thanks for the thread!! I don't have this device but to my amazement, this utility booted my Alcatel 3t 8 tablet into fastboot mode and I was bootloader unlocked in seconds! I can't thank you enough. This tool should be shared around. It may just be the key to unlocking the bootloader on a plethora of 2018+ MTK devices.

mickeybeats said:
Thanks for the thread!! I don't have this device but to my amazement, this utility booted my Alcatel 3t 8 tablet into fastboot mode and I was bootloader unlocked in seconds! I can't thank you enough. This tool should be shared around. It may just be the key to unlocking the bootloader on a plethora of 2018+ MTK devices.
Click to expand...
Click to collapse
Hi mickeybeats, I happen to have the Alcatel 3t 8 as well! I've been looking for a copy of the stock ROM/firmware everywhere and I'm unable to find it. Is it possible that you have a copy/know where I could download it? My tablet starting throwing up the feared "System UI has stopped" error and it seems reflashing stock ROM is the only way to fix it

I can confirm that the bootloader thing works for the 6058D model (MTK 6753)

For stock ROMs on Alcatel mtk devices, you need Sugar-mtk from Alcatel. It goes through the reflash process and as a bonus you can grab the firmware file from inside the flash tools program folders. The files don't use human readable formatting for the names but they end in either .bin or .mbn. A once over with a hexeditor should be enough to get a general idea of what they are. All the ones I've delt with had the boot.img label with a b at the beginning of the name and r for recovery, but gets a bit scattered from there.

stevegsames said:
I can confirm that the bootloader thing works for the 6058D model (MTK 6753)
Click to expand...
Click to collapse
Post your boot.img if you don't already have a custom recovery and I will build one for yours.

lehmancurtis said:
Post your boot.img if you don't already have a custom recovery and I will build one for yours.
Click to expand...
Click to collapse
I did make one, thank you though. If anyone's interested, here it is:
Idol 5 6058D TWRP
So, I recently revisited this phone and saw that there was a new exploit to access the bootloader. I tried it and it worked. After some time of trial and error, I was able to dump the stock recovery. With this, I started to port TWRP to it. This...
forum.xda-developers.com

stevegsames said:
I did make one, thank you though. If anyone's interested, here it is:
Idol 5 6058D TWRP
So, I recently revisited this phone and saw that there was a new exploit to access the bootloader. I tried it and it worked. After some time of trial and error, I was able to dump the stock recovery. With this, I started to port TWRP to it. This...
forum.xda-developers.com
Click to expand...
Click to collapse
Good to hear.

Hi all!
Is there anything similar to 'boot-mode too'l for Linux machines?
What would be a proper command-foo for this task?
The usual method with adb/fastboot obviously doesn't work with
Alcatel IDOL 5 (6058D/MT6753).
To install TWRP on Alcatel Idol 5, you first need to unlock the bootloader.The process is a bit more involved for this device than it is on most others.
Click to expand...
Click to collapse
Thanks!

elocnix said:
Hi all!
Is there anything similar to 'boot-mode too'l for Linux machines?
What would be a proper command-foo for this task?
The usual method with adb/fastboot obviously doesn't work with
Alcatel IDOL 5 (6058D/MT6753).
Thanks!
Click to expand...
Click to collapse
I don't know if it will work with wine. But you should be able to run it from a VM.

Don't be a idiot like me and accidently flash the recovery image on the Alcatel 3T 8. it will permanently brick the device and sugar-mtk will not restore .

How to root OPPO Find X2 Lite

Hello I want to root my phone because I use AAmirror (android auto mirror) in my car
I unlock boot loader tried KingRoot, KingoRoot, TowelRoot, I tried to install under ColorOs Recovery Magisk or SuperSu nothing work
Maybe solution could be to modify an existing original rom (I have last one) and flash it ?
It's a very good 5G phone for price but seems alone
thank you

Anyone successful with magisk? I wanted to unlock bootloader, but got stuck with the oppo chinese website not doing what I expected... I read somewhere it's not possible to replace recovery ROM with TWRP, but it's possible to boot it using ADB or Fastboot once. Has anyone been successful, can you share how-to?

nznatty said:
...using ADB or Fastboot once...
Click to expand...
Click to collapse
Perhaps something similar to:
(ROOT) Android 11 / Latest stock and patched img's / payload dumper / magisk_patched guides
Hi all, Have seen a lot of requests for patched boot images on these threads so thought i'd share a guide on how to get it yourself as well as all the files required, plus the patched boot.img if you just want to go ahead and boot/flash it...
forum.xda-developers.com

nznatty said:
Anyone successful with magisk? I wanted to unlock bootloader, but got stuck with the oppo chinese website not doing what I expected... I read somewhere it's not possible to replace recovery ROM with TWRP, but it's possible to boot it using ADB or Fastboot once. Has anyone been successful, can you share how-to?
Click to expand...
Click to collapse
hey..
this device is enter to fastboot mode.? when i use the command ; "adb reboot bootloader" device is try to enter fb mode but screen appears then gone..and rebooting to normal mode..i think e need patched aboot or boot or sth like that..

t-mobile_mda said:
hey..
this device is enter to fastboot mode.? when i use the command ; "adb reboot bootloader" device is try to enter fb mode but screen appears then gone..and rebooting to normal mode..i think e need patched aboot or boot or sth like that..
Click to expand...
Click to collapse
That's my experience so far too. I can't get the phone rooted, I think i'll put it back on ebay.

Looking to get that device for testing, I found this which may help: https://forum.xda-developers.com/t/magisk-root-install-with-unlocked-bootloader.4157327/

Is there a root for the ulefone Armor 9?

I have been looking for some sort of root for the ulefone armor 9, and I can't seem to find anything apart from sketchy websites. Can anyone help?

I found the scatterfile, but i still need to find the authentication file, and a download agent? I don't recall ever having to do any of this to root a phone before. Where do I get these files for a ulefone armor 9?

Look inside here:
Systemless Rooting with MagiskSU - Download APK
MagiskSU is an all-in-one Android rooting solution that is developed by topjohnwu. With Magisk Manager, users can easily root Android smartphones in a fastest and effective way. You can download MagiskSU, Magisk Root, Magisk Manager latest versions here.
magisksu.com

jwoegerbauer said:
Look inside here:
Systemless Rooting with MagiskSU - Download APK
MagiskSU is an all-in-one Android rooting solution that is developed by topjohnwu. With Magisk Manager, users can easily root Android smartphones in a fastest and effective way. You can download MagiskSU, Magisk Root, Magisk Manager latest versions here.
magisksu.com
Click to expand...
Click to collapse
there isn't a twrp for this phone.

M8E1 said:
there isn't a twrp for this phone.
Click to expand...
Click to collapse
TWRP isn't needed at all. Look inside here:
[Guide][Root] Magisk without TWRP on Android P
Via Magisk Manager: This method does not need root, and also does not require a custom recovery. However, you MUST have a stock boot image dump beforehand, and you also have to be able to flash the patched boot image, either through fastboot mode...
forum.xda-developers.com

jwoegerbauer said:
TWRP isn't needed at all. Look inside here:
[Guide][Root] Magisk without TWRP on Android P
Via Magisk Manager: This method does not need root, and also does not require a custom recovery. However, you MUST have a stock boot image dump beforehand, and you also have to be able to flash the patched boot image, either through fastboot mode...
forum.xda-developers.com
Click to expand...
Click to collapse
I did this, and I got a "red state" boot loop

M8E1 said:
I did this, and I got a "red state" boot loop
Click to expand...
Click to collapse
Am I missing something? The phone is apparently locked in fastboot mode, and will not accept downloads.

M8E1 said:
I did this, and I got a "red state" boot loop
Click to expand...
Click to collapse
Then report this issue in the related XDA-thread.

jwoegerbauer said:
Then report this issue in the related XDA-thread.
Click to expand...
Click to collapse
What thread would that be? This is for support and questions, isn't it?

M8E1 said:
What thread would that be? This is for support and questions, isn't it?
Click to expand...
Click to collapse
Of course this one:
[Guide][Root] Magisk without TWRP on Android P
Via Magisk Manager: This method does not need root, and also does not require a custom recovery. However, you MUST have a stock boot image dump beforehand, and you also have to be able to flash the patched boot image, either through fastboot mode...
forum.xda-developers.com

Is there anyone who can help? Fastboot does not respond to commands, and patching the boot.img and vbmeta.img via sp flash tool only puts my phone in a "red state". I have tried so many methods for rooting this phone, i'm starting to become convinced that it doesn't exist.

M8E1 said:
Is there anyone who can help? Fastboot does not respond to commands, and patching the boot.img and vbmeta.img via sp flash tool only puts my phone in a "red state". I have tried so many methods for rooting this phone, i'm starting to become convinced that it doesn't exist.
Click to expand...
Click to collapse
i rooted this phone on the first day i got,, i now trying to get proper working twrp so,, search on the google this,, ulefone armor 9 root hovatek and follow the guide there, thats how i did it.

kanadali said:
i rooted this phone on the first day i got,, i now trying to get proper working twrp so,, search on the google this,, ulefone armor 9 root hovatek and follow the guide there, thats how i did it.
Click to expand...
Click to collapse
Hello,
I tried to root my Armor 9E using Magisk but I ended with a bootloop. after a moment of stress (I'm a noob) I was able to put the original boot.img thanks to Fastboot,
I found your thread on Hovatek, how do you patch vbmeta.img ? in my case it's a Armor 9E
About TWRP, do you have any update ? will it be compatible with 9E also ?
Thanks
EDIT : I had to flash the vbmeta.img , I took it from hovatek here https://forum.hovatek.com/thread-36629.html

Totem95d said:
Hello,
I tried to root my Armor 9E using Magisk but I ended with a bootloop. after a moment of stress (I'm a noob) I was able to put the original boot.img thanks to Fastboot,
I found your thread on Hovatek, how do you patch vbmeta.img ? in my case it's a Armor 9E
About TWRP, do you have any update ? will it be compatible with 9E also ?
Thanks
EDIT : I had to flash the vbmeta.img , I took it from hovatek here https://forum.hovatek.com/thread-36629.html
Click to expand...
Click to collapse
Ok guys, don't stress out. I've been dealing with Ulefone for awhile now. I have about 20 of their phones and I have the Armor 9. I just rooted the Armor x7. To start with, Ulefone has the stock system files for download right there on their website for every model they sell.
You are going to need the SP flash tool. I think they even include it in their mega download page.
3086 Armor 9 - Google Drive
drive.google.com
Now these are Mediatek so they do things differently. You turn the phone off and start the flash on SP Flash tool and plug it in. You use the All-in-one authorization for it that's included. Find the special empty vbmeta file on hovatek and use it in place of the other one. Remove the checksum.ini file.
But before all this when you got the boot off of there put it on your sdcard and install Majisk manager. Tell it to install magisk and to patch your boot. Pick the boot file. Then adb pull that file onto your computer and name it boot.img
put all of them back together in place of the old ones with all the stuff you downloaded from the ulefone link and run the checksum generator that it comes with which will produce a checksum.ini file. And if you have that empty vbmeta also you can use SP flash to flash it to your phone and it'll take it. You'll be left with a yellow or orange state then relock your bootloader and you'll be back to normal with magisk installed and root. So...you know, Friggin Mediatek
The reason for your bootloop was because you didn't put the empty vbmeta file in the mix.

MurdochPizgatti said:
Ok guys, don't stress out. I've been dealing with Ulefone for awhile now. I have about 20 of their phones and I have the Armor 9. I just rooted the Armor x7. To start with, Ulefone has the stock system files for download right there on their website for every model they sell.
You are going to need the SP flash tool. I think they even include it in their mega download page.
3086 Armor 9 - Google Drive
drive.google.com
Now these are Mediatek so they do things differently. You turn the phone off and start the flash on SP Flash tool and plug it in. You use the All-in-one authorization for it that's included. Find the special empty vbmeta file on hovatek and use it in place of the other one. Remove the checksum.ini file.
But before all this when you got the boot off of there put it on your sdcard and install Majisk manager. Tell it to install magisk and to patch your boot. Pick the boot file. Then adb pull that file onto your computer and name it boot.img
put all of them back together in place of the old ones with all the stuff you downloaded from the ulefone link and run the checksum generator that it comes with which will produce a checksum.ini file. And if you have that empty vbmeta also you can use SP flash to flash it to your phone and it'll take it. You'll be left with a yellow or orange state then relock your bootloader and you'll be back to normal with magisk installed and root. So...you know, Friggin Mediatek
The reason for your bootloop was because you didn't put the empty vbmeta file in the mix.
Click to expand...
Click to collapse
Trying this method works fine for me until I try to relock the bootloader. Once I do that, I end up with a red state again.
Any advice? I am relocking the bootloader via fastboot flashing lock - is that correct?

MurdochPizgatti said:
Ok guys, don't stress out. I've been dealing with Ulefone for awhile now. I have about 20 of their phones and I have the Armor 9. I just rooted the Armor x7. To start with, Ulefone has the stock system files for download right there on their website for every model they sell.
You are going to need the SP flash tool. I think they even include it in their mega download page.
3086 Armor 9 - Google Drive
drive.google.com
Now these are Mediatek so they do things differently. You turn the phone off and start the flash on SP Flash tool and plug it in. You use the All-in-one authorization for it that's included. Find the special empty vbmeta file on hovatek and use it in place of the other one. Remove the checksum.ini file.
But before all this when you got the boot off of there put it on your sdcard and install Majisk manager. Tell it to install magisk and to patch your boot. Pick the boot file. Then adb pull that file onto your computer and name it boot.img
put all of them back together in place of the old ones with all the stuff you downloaded from the ulefone link and run the checksum generator that it comes with which will produce a checksum.ini file. And if you have that empty vbmeta also you can use SP flash to flash it to your phone and it'll take it. You'll be left with a yellow or orange state then relock your bootloader and you'll be back to normal with magisk installed and root. So...you know, Friggin Mediatek
The reason for your bootloop was because you didn't put the empty vbmeta file in the mix.
Click to expand...
Click to collapse
Hi!
I'm having the same issue as MulBe039.
Device: UleFone Armor 9E (Android 10)
My steps so far:
0.0 Get boot.img, scatter file, checksum generator (from ulefone), magisk.apk (from github), vbmeta.img, drivers, SP Tool (from Hovatek)
0.1 Install magisk on my phone and patch boot.img.
0.2 Enable developer options on my phone
0.3 Enable OEM unlocking and USB debugging on my phone.
0.4 Install drivers on my PC
0.5 Copy scatterfile, boot.img, vbmeta.img into checksum generator's folder and get checksum.ini.
1.0 Connect phone
> adb devices
> adb reboot bootloader
> fastboot devices
> fastboot oem unlock
> fastboot reboot
Phone boots in orange state.
2.0 Re-enable dev opts, (phone shows as already unlocked), USB debugging and turn off the phone.
2.1 Start SP Flashtool
2.2 Select scatter file
2.3 Check only vbmeta.img
2.4 Start download
2.5 Connect phone
2.6 Download completes successfully.
2.7
> fastboot devices
> fastboot reboot
Orange state.
2.8 Factory reset from phone
3. Repeat 2., except at 2.3 check only the patched boot.img
Still orange state.
Magisk app is installed.
4.0 Turn the phone on, enable dev opts and USB debugging, connect to PC
> adb devices
> adb reboot bootloader
> fastboot devices
> fastboot oem lock
> fastboot reboot
Red state - boot loop.
5.0 Hold power button until it turns off abruptly
5.1 Hold volume up until load some sort of boot selector menu.
5.2 Select fastboot mode with vol up button.
5.3 Vol down to boot selected mode
5.4
> fastboot devices
> fastboot oem unlock
> fastboot reboot
Orange state - everything else is working.
What am I missing / doing wrong? How do I re-lock the bootloader?
Thanks in advance!

I have been able to root my Ulefone armor 9 using the method described here https://github.com/bkerler/mtkclient
1 - download boot partition from your device using mtkclient
2 - patch it with magisk manager
3 - flash it again with mtkclient
4 - flash an empty vbmeta (not really sure if this is necessary)
5 - boot your device
I'm not really sure if it is needed to have the bootloader unlocked, but I had it

0xf331dead said:
I have been able to root my Ulefone armor 9 using the method described here https://github.com/bkerler/mtkclient
1 - download boot partition from your device using mtkclient
2 - patch it with magisk manager
3 - flash it again with mtkclient
4 - flash an empty vbmeta (not really sure if this is necessary)
5 - boot your device
I'm not really sure if it is needed to have the bootloader unlocked, but I had it
Click to expand...
Click to collapse
And remember that you cannot lock your bootloader after modifying stuff because signatures will not match and so on

I had to press volume up + volume down while connecting the usb to get mtkclient working

[SOLVED] Doogee S88 Plus reboot loop with magisk root

after patching boot.img with Magisk and flashing over the patched boot.img, the phone (Doogee S88 Plus) will just infinitely reboot after the message `Your device has been unlocked and can't be trusted`
luckily, patching the original boot.img back fixes it (albeit flashing it back is kindof tricky, have to reboot multiple times while holding down the volume-down button before i can re-flash)
so it's not bricked, but i haven't been able to root it either, any suggestions?
fwiw, i'm using this firmware: https://drive.google.com/drive/folders/13bxhk-eEsJ81FmJWZaEEsOkZBMsYJE3x

update: finally managed to root it, the final piece of the puzzle was that S88 Plus wanted the magisk-patched boot.img signed with the publicly-available-private-key from https://forum.hovatek.com/thread-35862.html
screenshot:
https://imgur.com/EbjK0qX

the magisk-patched + signed boot.img if anyone is interested:

where boot.img ?

and you chose which twrp ?

avalondrey said:
where boot.img ?
Click to expand...
Click to collapse
avalondrey said:
and you chose which twrp ?
Click to expand...
Click to collapse
i did not use twrp at all, i only used magisk, and the boot.img is the file i uploaded above with the name "magisk_patched-23000_TY62U.img" , just rename it to "boot.img"

does your phone has a vbmeta.img?
It control if the image is signed, if you don't flash an empy vbmeta.img the system will bootloop.
It was a problem when rooting the Ulefone Armor 8-11

root is ok , flash tool, install boot and reboot

Harlock1978 said:
does your phone has a vbmeta.img?
It control if the image is signed, if you don't flash an empy vbmeta.img the system will bootloop.
It was a problem when rooting the Ulefone Armor 8-11
Click to expand...
Click to collapse
interesting, yes the phone has a vbmeta.img, and no i did not patch the vbmeta.img, and i did experience the reboot-loop, but signing the patched boot.img fixed the reboot loop without touching the vbmeta.img

This did it..dont flash vbmeta...the Boot ist the only Thing you Need...flashing vbmeta will end in bootloop...maybe a signed vbmeta...but why trying when Boot is enough...

after hours of trying I finally got it working.
Because I tried so much stuff I'm not exactly sure what was the key.
The signed boot.img flashed with sp flash tool alone did not work - i did not have the device unlocked with fastboot at that moment.
Then I tried a lot of different stuff.
I _think_ what was needed is these two things:
- signed boot.img from @hans henrik
- unlocking bootloader with fastboot (fastboot flashing unlock && fastboot flashing unlock_critical)

How did you unlocked it? And are you running gsi rom?
I have the s88 pro and i like to install custom rom

the doogee s88 plus should support galileo GPS standard Pu on mine it does not show any gaileo satelites. could anybody check?

Hi please help me i have doogee S88 plus and i use this guild https://unofficialtwrp.com/twrp-3-4-0-root-doogee-s88-plus/
now me phone keeps restarting, show "orange state", logo launches, I tried different combinations of buttons but nothing helped
what can i do or is there any way i can get it back to normal?
only now found this thread, currently the phone has a bootloop after these three commands
fastboot erase userdata
fastboot flash vbmeta vbmeta.img
fastboot flash recovery recovery.img

OK, i use sp flash tool but when i turn on me phone i see a bars on screen
i tried with all the stock roms i found, everywhere the same, the phone seems to work but instead of images there are stripes
this rom worked
OneDrive
onedrive.live.com

I finally managed to root my phone after days of endless boot loops (fixed by flashing stock using SP flash tool). Turns out I didn't need to flash an empty vbmeta or install TWRP at all. I was able to root it by following this guide https://www.hovatek.com/forum/thread-35862.html. For some reason your patched magisk image didn't work on my S88 Plus, so I made my own using the stock boot image from the official Doogee website (which appears to be the same one used in your patched version?) and Magisk 25.2 apk. For the Hovatek guide, I used python2 since python and python3 did not work. I currently have a red "Not Verify" watermark and an NVRAM WARNING: Err = 0x10 wifi network error, but should be able to resolve those with root access from guides I read earlier.
I would also like to install a GSI (lineageos preferably) but have had no success since nothing seems to officially support the S88 Plus even though it is project treble compatible, and I have ran into boot loops so far.
I have attached my working magisk_patched.img but would recommend building it from scratch using the linked guide to avoid any issues.

How to install a GSI? (I have a problem).

Hello.
I find myself with the need to install a GSI in my Samsung Galaxy A7 (2018) (A750G), since with the stock firmware, for some strange reason the power button does not unlock the screen.
The thing is, I was previously using Phhussom's GSI AOSP (https://github.com/phhusson/treble_experimentations) with TWRP recovery (https://forum.xda-developers.com/t/recovery-root- twrp-3-2-3-1-galaxy-a7-2018-a750.3876798 /) and after re-flashing the stock firmware, now I find that the TWRP I was using does not work, which led me to use this recovery https://forum.xda-developers.com/t/recovery-unofficial-pbrp-3-1-0-for-galaxy-a7-2018.4280553 and try again to install the Phhussom GSI AOSP.
However I did not succeed. And after following many guides that had incomplete files (dead links) or methods that do not work, I find myself with the problem of not being able to install GSIs.
Does anyone know any method that works? I am puzzled.

Never flash GSI with Custom Recovery. GSIs are meant to be flashed by fastboot mode with command-line commands.

LinhBT said:
Never flash GSI with Custom Recovery. GSIs are meant to be flashed by fastboot mode with command-line commands.
Click to expand...
Click to collapse
Samsung does not have fastboot.

uphragbvfccved said:
Samsung does not have fastboot.
Click to expand...
Click to collapse
It just under different name, and have weird way to boot into it. At the end of the day, no android devices can work without bootloader is it my friend?

just flash a older version of the firmware i.e a november 2020 firmware

LinhBT said:
It just under different name, and have weird way to boot into it. At the end of the day, no android devices can work without bootloader is it my friend?
Click to expand...
Click to collapse
As far as I have concerned, the bootloader mode (ADB reboot bootloader) redirects to download mode, which only supports .tar images.
Also, a bootloader can exist without fastboot. Activating every piece of hardware, load the drivers, load the kernel, and give control to the Android OS, which as far as I know is what the bootloader does, does not necessarily need a user accessible fastboot mode.
There is still a way to flash GSI in theory, by renaming the gsi system.img, putting it into a zip, and rename the zip into xxx.tar, and Odin flash it. No guarantees though.

LinhBT said:
weird way
Click to expand...
Click to collapse
Are you going to show us how to short circuit testpoints and make fastboot commands magically work on a Samsung phone?

LR7875 said:
Are you going to show us how to short circuit testpoints and make fastboot commands magically work on a Samsung phone?
Click to expand...
Click to collapse
1. Testpoint is diff from each device, and I think you can easily find it for your device on google.
2. Yes, a bootloader, in fact, exist in almost every devices, only be called with different names ( like BIOS on the computer ). About it's functions, yes, you listed some of those. But one thing you may mis-understanding : Fastboot. Fastboot or fastbootD or Download mode, are just names. And they are, in fact, is the bootloader command-line environment. Besides, flashing a GSI on Samsung device is not that complicated, I think you guys may look on other places than just XDA to find solutions sometimes.

Ok to me it is not too easy to search a method to use command line mode on Samsungs.
As far as I know fastboot commands does not work in Odin download mode.
For those interested in custom recoverys, some custom recoverys succeed in flashing GSIs on a galaxy J7 pro (android 7, unofficial project treble port)with h-vendor BUT at the end of the day it might not work on newer devices like the A7, because of vertified boot( AVB 2.0) that is putted into android since Oreo! And AVB 2.0 is the real thing that you need to disable via a command line interface.

LinhBT said:
Never flash GSI with Custom Recovery. GSIs are meant to be flashed by fastboot mode with command-line commands.
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Can you point to a good guide/tutorial on howto do this?

blazzer12 said:
Can you point to a good guide/tutorial on howto do this?
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As I mentioned, I always use command-line to flash GSI. The order and commands may a little different from devices, but basically should be as below :
- adb reboot bootloader ( to boot into bootloader enviroment )
- fastboot devices ( to check and verify the connetion between computer and devices, can be skipped )
- fastboot reboot fastboot ( to boot into fastboot/fastbootD/Download mode - names may different from devices. Also, in some device, as for Scamsung, can be different - also depends on devices )
- fastboot --disable-verification flash vbmeta vbmeta.img ( to flash blank/patched vbmeta.img into vbmeta partition, some devices don't need this step )
- fastboot erase system ( erase system partition )
- fastboot flash system system.img ( flash system.img into system partition )
- fastboot -w ( do a factory reset )
- fastboot reboot bootloader ( boot back to bootloader enviroment )
- fastboot erase userdata ( erase userdata partition to prevent configs, same as you do the wipe data in OF or other custom recoveries )
- fastboot reboot ( yeah, it is )
As I mentioned before, this's only the basic structure of commands to flash a GSI ( apply for dynamic partition devices also ). Depends on which device u have, may need to slightly change the commands or order. Means, this method is not applied for ALL DEVICES.
Last but not least, always have backups and do find other solutions may have to figure out which is right for you, do things at your own risks.

Samsung does not support fastboot so I used heimdall still resulted in bootloop. Are you sure system parition needs to be erased?
Can you tailor this to "Samsung Galaxy A7 (2018)" a bit?

LR7875 said:
AVB 2.0 is the real thing that you need to disable via a command line interface.
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How to do it for A7?

blazzer12 said:
How to do it for A7?
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Only devices launched after 2018 have this.