Android Enthusiasts Stack Exchange
Android Enthusiasts Stack Exchange

Questions tagged [bootloader]

for questions on the bootloader, which is kind of "BIOS mode" on Android devices

The bootloader (also called "SPL" for "Secondary Program Loader") is started shortly after the device's basic checks (baseband, the "primary loader") and is responsible for loading the (Android) OS. It can be used to boot different custom ROMs besides the stock firmware, sometimes even a different Linux distribution, if the bootloader is unlocked.

You can compare the combination of Baseband + Bootloader with the BIOS of a PC + boot manager (e.g. Grub/LiLo, which are also called "Second Stage Bootloaders"). One can boot directly into bootloader mode1 (like one boots into BIOS) for special operations. This is e.g. required for operating , and .

Side-note: As this is a very rudimentary/basic mode, there's no available here, nor do the settings made in Android itself (e.g. ) have any effect here, naturally.

1 For how to get into bootloader mode, please check our fastboot tag-wiki.

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Where is the code for the Bootloader stored in an Android phone?

Where is the bootloader program on an Android phone stored ?
progammer
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What is S-OFF? Why would I want to do it?

I always root my android devices, but there's something called obtaining S-OFF for certain devices, and I have no idea what that means. What exactly does the term S-OFF relate to? Why would I want to obtain S-OFF for my device?
John
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What does HBOOT mean?

My best guess as of now is "partition and mount point layout". But it feels like there's more to it, since the bootloader can identify the HBOOT by name. I've been flashing custom ROMs for quite a while now, but I still haven't quite grasped what…
Emil Lundberg
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Is there a way to tell if a boot loader can be unlocked before purchase?

For example are boot loaders unlockable only if the phone is branded and comes with a contract? If I bought a phone of Amazon.com would I likely be able to unlock the boot loader or is it really just luck of the draw?
Celeritas
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su fails: "wget: bad address 'static.zhiqupk.com'" and unable to unlock bootloader

A friend of mine bought a used Samsung Galaxy S6 or at least we thought so, but it looks that it might be a chinese phone. After wiping all data/cache, the phone still had a lot porn/advertisement apps, so we decided to burn original ROM. The only…
Sasa
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Android tablet won't reboot after rebooting using volume and power buttons

I am using a 7" Smartfren tablet called S7. I was following this tutorial. When I got the last part about the bootloader, I turned my device off. I tried to reboot using the volume buttons and power button, but it won't open up. Also, it cannot be…
John Ernest Guadalupe
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Unlocking Bootloader to wipe internal storage

I know that unlocking bootloader does wipe the /data partition. However, can it also wipe the /storage partition and others, too?
user167294
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Can we mod android phones using custom bootloader, firmware for MSM8909 Snapdragon 210

Can we mod android phones using custom bootloader (sbl secondary bootloader) , firmware for MSM8909 Snapdragon 210 (phone is zte835). Deleting all factory firmware, bootloader and using custom bootloader and Roms. I deleted sbl boot files while…
user399774
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How executable binary can be signed?

On most Android devices, the bootloader checks following bootloader/software sign, right? Chain of trust. Signing technically means that the file must be encrypt with one (private) key and decrypted with another (public) key. The software is…
user385781
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is it possible to replace the bootloader firmware to unlock a 64bits cpu?

Sm-j700m cpu is arm64 but only allows 32bits android on it. From here: https://www.reddit.com/r/LineageOS/comments/p9p3s3/comment/h9zan52/ I thought that, if the bootloader could be replaced or tweaked (change some bytes on it), it could allow…
VeganEye
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If I unlock the FRP on my Samsung S7, can I root my phone?

I'm having a lot of trouble to unlock the bootloader, but managed to unlock the FRP. Can I root the phone? Also, while on download mode, is it required to use a USB original cable? My download mode info is: ODIN MODE DOWNLOAD SPEED: FAST PRODUCT…
user323215
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What is the lock in bootloader?

I know how to unlock. It's through fastboot oem unlock. I know why the manufactures place a lock. It's for security reasons. But what is the lock? Is it a file in the system, saying "Hey, the bootloader is locked! Delete me if you want to unlock!",…
Gqqnbig
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Why are bootloaders in rewritable storage?

I successfully flashed my device a few times, but I am still paranoid about hard bricks. I am sure I can use my Arduino to fix them, but this made me wonder why bootloaders are stored in rewritable storage. I am aware that there is a PBL and an SBL…
person
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How to check if bootloader is open?

1) How can I check if the bootloader of a Nexus 5x is open? (GSM Code? App? ADB?) 2) Is it still correct that only the manufacturer can close the bootloader once it has been opened? Or is it already possible to close it by yourself? Hint: I bought…
user3200534
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Replacing Boot loader

i want to replace my nexus 6 stock boot loader with the one i customized based on little kernel. but as long as i know there is a authentication chain from the very start of booting process in boot ROM to the start of android itself. so is it really…
ramin
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