PC recovery similarities to TWRP - G4 General

What would be the PC equivalent of Custom Recovery software like TWRP?
Would it be something like Acronis TrueImage ?
Also, would it make sense to say that a locked bootloader in a phone (PS: Notice I won't say 'Android Device', because the bootloader comes into play BEFORE the Android OS) is the equivalent of having 'secure boot' enabled in UEFI in a Windows PC? Thereby implying that the process of disabling Secure Boot in UEFI in a PC is the same as unlocking the bootloader in phones?

BIG_BADASS said:
What would be the PC equivalent of Custom Recovery software like TWRP?
Would it be something like Acronis TrueImage ?
Also, would it make sense to say that a locked bootloader in a phone (PS: Notice I won't say 'Android Device', because the bootloader comes into play BEFORE the Android OS) is the equivalent of having 'secure boot' enabled in UEFI in a Windows PC? Thereby implying that the process of disabling Secure Boot in UEFI in a PC is the same as unlocking the bootloader in phones?
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I really don't think you get how phones work bro. Unlocking a bootloader can only be done by manufacturing or through more aggressive means when possible. The H812 still hasn't had its bootloader unlocked by lg and at this point probably never will
Sent from my LG-H812 using Tapatalk

SpyderAByte said:
I really don't think you get how phones work bro. Unlocking a bootloader can only be done by manufacturing or through more aggressive means when possible. The H812 still hasn't had its bootloader unlocked by lg and at this point probably never will
Sent from my LG-H812 using Tapatalk
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That doesn't answer my question. I asked the theoretical side, not practical.
Before you do anything, you must understand the FULL boot sequence and structure of Smartphone with ARM chipset, and compare it to Intel x86 Chipset..... and know the relationships well... THEN only you can safely say "I know this" ... THEN only you can safely play around and tinker with the smart phones.....
I thought I knew alot.. but turns out I know NOTHING.... so I go back to square 1 and learn EVERYTHING from scratch again.....
Before I do anything, I must familiarize WHAT is TWRP.. You can say "TWRP is custom recovery", okay, 'WHAT IS CUSTOM RECOVERY' ? You must be able to clearly explain what it is, what parts of the boot sequence it affects.... what is the equivalent in an Intel x86 PC of TWRP or custom recovery????
WHat is a ROM? We all know ROM in smartphone world is more than just the operating system... So what other components does it replace besides the operating system???
We have to think like this and analyze EVERYTHING, all the relationships between all the entities.....
I am now learning about EMBEDDED LINUX ... and the boot sequence of it... as smartphone is just another version of embedded linux......
This is what I'm doing now... when I am familiar with EVERYTHING.... then I will tinker....

BIG_BADASS said:
That doesn't answer my question. I asked the theoretical side, not practical.
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Click to collapse
Secure boot on windows acts as a UEFI (modernized motherboard BIOS meant to work better and faster with x64 and newer systems)
Locker to prevent UEFI from booting into unsigned/unrecognized system images (as far as I know, anybody feel free to correct me)
Bootloaders on smartphones would be the equivalent of a UEFI for the arm architecture. Meant to guide the system into booting from a specified mount. Bootloaders are coded by the manufacturer, either locked or unlocked. Unlocked bootloaders provide a way for users to enter recovery mode and potentially flash unsigned/custom images. If the manufacturer decides to lock the bootloader, the only options are wait for a way to unlock from manufacturer or find a way to crack it if you have the know how
Some manufacturers use the same bootloader for all or most variants of one phone, or can use a different bootloader for each variety of a phone, choosing which bootloaders to unlock or leave locked
For example with the Lg G4, the international variant H815 I believe is unlocked, while the H812 is still to this day locked, while unfortunately their has not been enough interest in trying to reverse engineer or find a loophole if even possible

SpyderAByte said:
Secure boot on windows acts as a UEFI (modernized motherboard BIOS meant to work better and faster with x64 and newer systems)
Locker to prevent UEFI from booting into unsigned/unrecognized system images (as far as I know, anybody feel free to correct me)
Bootloaders on smartphones would be the equivalent of a UEFI for the arm architecture. Meant to guide the system into booting from a specified mount. Bootloaders are coded by the manufacturer, either locked or unlocked. Unlocked bootloaders provide a way for users to enter recovery mode and potentially flash unsigned/custom images. If the manufacturer decides to lock the bootloader, the only options are wait for a way to unlock from manufacturer or find a way to crack it if you have the know how
Some manufacturers use the same bootloader for all or most variants of one phone, or can use a different bootloader for each variety of a phone, choosing which bootloaders to unlock or leave locked
For example with the Lg G4, the international variant H815 I believe is unlocked, while the H812 is still to this day locked, while unfortunately their has not been enough interest in trying to reverse engineer or find a loophole if even possible
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Thank you bro... now we're getting somewhere....
So PCs also have a bootloader.... but the way I understand, "Bootloader" in the smartphone is a combination of BIOS and MBR in the pc world, right? It is all combined into one entity called "Bootloader"...
Also, the MBR usually has a Stage 1 bootloader, which points to a stage 2 bootloader, which is installed somewhere in the permanent memory (hard disk in PC).... but this structure is not the same in smartphone I believe?

The arm architecture is completely different than the x86 or x64 architectures.
As Asus and MSI and acer etc have their own bios,
Samsung, lg, HTC Huawei Google etc have their own bootloaders. Twrp for example is a custom open source bootloader that anybody can get the source and add to. Phone companies do not give out the source code for their bootloaders usually and it is in their own power to lock and unlock them
Sent from my LG-H812 using Tapatalk

SpyderAByte said:
Maybe just get an unlocked international variant of your next phone and let the big boys do the work for you
Sent from my LG-H812 using Tapatalk
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Yes, that would be the easy way around...
I have the H815 now which I got in exchange for H812... anyways.... if I didn't have it the hard way, I wouldn't learn anything..... If I had the unlockable H815 from day 1, I wouldn't be this curious... therefore I wouldn't learn.. I'd just be living in ignorance thinking I know everything there is to know .....

Why don't you start by finding the twrp out for the h815 and tinkering with it, making it your own. Try finding a stock ROM and tinkering with that building your own. Plenty of guides around the internet. Learn java and take flight bud
Sent from my LG-H812 using Tapatalk

SpyderAByte said:
The arm architecture is completely different than the x86 or x64 architectures.
As Asus and MSI and acer etc have their own bios,
Samsung, lg, HTC Huawei Google etc have their own bootloaders. Twrp for example is a custom open source bootloader that anybody can get the source and add to. Phone companies do not give out the source code for their bootloaders usually and it is in their own power to lock and unlock them
Sent from my LG-H812 using Tapatalk
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SpyderAByte said:
The arm architecture is completely different than the x86 or x64 architectures.
As Asus and MSI and acer etc have their own bios,
Samsung, lg, HTC Huawei Google etc have their own bootloaders. Twrp for example is a custom open source bootloader that anybody can get the source and add to. Phone companies do not give out the source code for their bootloaders usually and it is in their own power to lock and unlock them
Sent from my LG-H812 using Tapatalk
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Yes, in the x86 world they do have different motherboard architectures, hence different BIOS's ... but the rest of the boot sequence follows the same order......
So that brings me to my next question... why is it that we can hard brick a phone, but not a PC? I mean.. technically it is possible to brick a PC if you screw up a bios flash.... but that just leads me to believe a "ROM" in smartphone world actually consists of BIOS + OS ...
So that leads me to wonder.. what else has combined functionality? What is the BIOS equivalent in Android? I mean.. technically it is possible to brick a PC if you screw up a bios flash.... but that just leads me to believe a "ROM" in smartphone world actually consists of BIOS + OS ...
So that leads me to wonder.. what else has combined functionality? What is the BIOS equivalent in Android?

The bootloader partition/iso and the data/android partition/ROM are 2 different things
You can independently swap your recovery if it's unlocked and keep your data. Or you can independently change ROMs and keep your bootloader. You don't seem to understand this pretty basic concept
You can brick a phone flashing the bootloader incorrectly or by flashing the ROM incorrectly
Likewise on a PC if you flash the bios/UEFI incorrectly you can brick your motherboard, and corrupting your OS installation can cause issues
The reason you've bricked phones more than you've bricked computers - when was the last time you tried flashing a custom bios or UEFI? Or a version of Linux/windows that your bios won't allow
Computers are usually pretty plug and play so you can swap HDDs/ram/processors and simply upgrade needed drivers to works
Smartphones are greasy and closed source and the manufacturer usually wants it their way, that's why you see them blocking root access and custom roms
Sent from my LG-H812 using Tapatalk

SpyderAByte said:
The bootloader partition/iso and the data/android partition/ROM are 2 different things
You can independently swap your recovery if it's unlocked and keep your data. Or you can independently change ROMs and keep your bootloader. You don't seem to understand this pretty basic concept
You can brick a phone flashing the bootloader incorrectly or by flashing the ROM incorrectly
Likewise on a PC if you flash the bios/UEFI incorrectly you can brick your motherboard, and corrupting your OS installation can cause issues
The reason you've bricked phones more than you've bricked computers - when was the last time you tried flashing a custom bios or UEFI? Or a version of Linux/windows that your bios won't allow
Computers are usually pretty plug and play so you can swap HDDs/ram/processors and simply upgrade needed drivers to works
Smartphones are greasy and closed source and the manufacturer usually wants it their way, that's why you see them blocking root access and custom roms
Sent from my LG-H812 using Tapatalk
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So basically, the ROM is more than just the operating system, no? Flashing a rom in smartphone is NOT exactly the same as installing Ubuntu or Debian in a PC, right? There's something else you're replacing, am I right?
Also.. the way I understand... Bootloader is the very first software that runs once you power on the smartphone? (equivalent of BIOS) ?

BIG_BADASS said:
So basically, the ROM is more than just the operating system, no?
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The ROM is the operating system, the included apps and packages and any other information that android needs to run after the bootloader
Sent from my LG-H812 using Tapatalk

SpyderAByte said:
The ROM is the operating system, the included apps and packages and any other information that android needs to run after the bootloader
Sent from my LG-H812 using Tapatalk
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So when you flash a rom, you're not replacing the original bootloader? Or BIOS?

No as I stated in my previous post. You can use your bootloader or a PC through fastboot to flash ROMs as long as your bootloader is unlocked
On a galaxy for instance you could first install twrp if possible leaving your stock touchWiz ROM perfectly intact but now you have twrp
Then later you can use twrp to install paranoid Android or CM for instance, replacing your stock touchWiz ROM, but leaving your newly installed twrp untouched
I used to have a galaxy s4 Canadian variant, and the bootloader was locked and still is to this day. The only way to flash a custom ROM was to bypass the stock bootloader using a method found by someone experienced with Samsung bootloaders (a rogue Samsung employee iirc)
Sent from my LG-H812 using Tapatalk

SpyderAByte said:
Bootloaders on smartphones would be the equivalent of a UEFI for the arm architecture. Meant to guide the system into booting from a specified mount. Bootloaders are coded by the manufacturer, either locked or unlocked. Unlocked bootloaders provide a way for users to enter recovery mode and potentially flash unsigned/custom images. If the manufacturer decides to lock the bootloader, the only options are wait for a way to unlock from manufacturer or find a way to crack it if you have the know how
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The final outcome is the same, yes, but bootloader and BIOS/UEFI are completely separate, right? X86 PCs have a bootloader called NTLDR and it comes into play after the BIOS has finished POST and given control to the MBR....
BIOS > MBR (contains stage 1 bootloader) > Stage 1 bootloader points to Stage 2 bootloader in the HDD
Or is the functionality of bootloader and bios combined into one unit in the smartphone?
---------- Post added at 07:09 AM ---------- Previous post was at 07:05 AM ----------
SpyderAByte said:
No as I stated in my previous post. You can use your bootloader or a PC through fastboot to flash ROMs as long as your bootloader is unlocked
On a galaxy for instance you could first install twrp if possible leaving your stock touchWiz ROM perfectly intact but now you have twrp
Then later you can use twrp to install paranoid Android or CM for instance, replacing your stock touchWiz ROM, but leaving your newly installed twrp untouched
I used to have a galaxy s4 Canadian variant, and the bootloader was locked and still is to this day. The only way to flash a custom ROM was to bypass the stock bootloader using a method found by someone experienced with Samsung bootloaders (a rogue Samsung employee iirc)
Sent from my LG-H812 using Tapatalk
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So TWRP comes into play before the operating system is loaded, correct? Meaning if you flash a corrupt operating system, you can still format the drive, because TWRP is on a lower layer?
So you can think of TWRP as those Windows Recovery disks?

Do you understand how partitions work? (Not attacking, honest question)
Your bootloader would sit on one partition of the phone emmc(like a small solid state drive/kind of like an sd card chip)
So your partition table would look kind of like this
Emmc1 - /boot (bootloader tells android to boot into recovery, download, fastboot, or android rom
Emmc2 - /recovery (recovery partition. User interface of twrp for example)
Emmc3 - /download mode (used to flash zips)
Emmc4 - /data (android rom that you install
Emmc5 - / (the root folder of your phone, where your storage starts
If you remember getting a 16gb iPhone or iPod and wondering why you only got 9-11gb when you have 100% free space, it's because the emmc is rated for 16gb but the data/ROM uses 5-7gb
Sent from my LG-H812 using Tapatalk

SpyderAByte said:
Do you understand how partitions work? (Not attacking, honest question)
Your bootloader would sit on one partition of the phone emmc(like a small solid state drive/kind of like an sd card chip)
So your partition table would look kind of like this
Emmc1 - /boot (bootloader tells android to boot into recovery, download, fastboot, or android rom
Emmc2 - /recovery (recovery partition. User interface of twrp for example)
Emmc3 - /download mode (used to flash zips)
Emmc4 - /data (android rom that you install
Emmc5 - / (the root folder of your phone, where your storage starts
If you remember getting a 16gb iPhone or iPod and wondering why you only got 9-11gb when you have 100% free space, it's because the emmc is rated for 16gb but the data/ROM uses 5-7gb
Sent from my LG-H812 using Tapatalk
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Sorry man, I'm from the PC world.. this makes no sense to me.... please relate all the functionality to it's PC equivalent...
Also, what is the boot sequence of the smartphone? Does it have a BIOS? MBR? Hard Drive? RAM?
If smartphone doesn't have all these parts, then what part of the phone does the job of the BIOS, MBR, Hard drive, RAM, bootloader, etc?
---------- Post added at 07:27 AM ---------- Previous post was at 07:20 AM ----------
Maybe my approach here is wrong, maybe I shouldn't try to relate everything 1 to 1 ?
---------- Post added at 07:48 AM ---------- Previous post was at 07:27 AM ----------
SpyderAByte said:
Do you understand how partitions work? (Not attacking, honest question)
Your bootloader would sit on one partition of the phone emmc(like a small solid state drive/kind of like an sd card chip)
So your partition table would look kind of like this
Emmc1 - /boot (bootloader tells android to boot into recovery, download, fastboot, or android rom
Emmc2 - /recovery (recovery partition. User interface of twrp for example)
Emmc3 - /download mode (used to flash zips)
Emmc4 - /data (android rom that you install
Emmc5 - / (the root folder of your phone, where your storage starts
If you remember getting a 16gb iPhone or iPod and wondering why you only got 9-11gb when you have 100% free space, it's because the emmc is rated for 16gb but the data/ROM uses 5-7gb
Sent from my LG-H812 using Tapatalk
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Also, lets say you format the entire memory of the phone, and reinstall Android.... will it automatically create all these partitions?

Holy **** man you say you know computers but it's almost the same as Linux. Android uses Linux at its absolute core so alot of it is pretty close. Look up a healthy Linux partiton setup and compare to my half assed partition table above and you'll see it's almost identical.
A HDD, SSD, or a memory block (phone internals, usb drives, sd cards) all can have seperate "partitions" which are basically seperate simulated drives, and all have a master boot record telling the device where to start.
There is a boot partition on the memory block which holds the core bootloader files and tells the phone what to do first.
If you hold down the recovery button it will tell the phone to boot to the recovery partition. If you hold down the download buttons it will tell the phone to boot into the download partition. If you allow the phone to boot regularly it will tell the phone to boot to the android /system partition which is where the android operating system is held
I can't explain how this works compared to windows because windows does its own thing in regarding to booting and it is not in my spectrum
The paranoidAndroid.iso file system you would try to flash for example would hold the
/system(android os)
/Data (user data and apps)
/ Or /root (main read/write accessable storage for user)
/Root would require root access to be able to get into and from there you can access the /system and /data mountpoints to modify system files, without root access you are usually not even able to view these folders

SpyderAByte said:
Holy **** man you say you know computers but it's almost the same as Linux. Android uses Linux at its absolute core so alot of it is pretty close. Look up a healthy Linux partiton setup and compare to my half assed partition table above and you'll see it's almost identical.
A HDD, SSD, or a memory block (phone internals, usb drives, sd cards) all can have seperate "partitions" which are basically seperate simulated drives, and all have a master boot record telling the device where to start.
There is a boot partition on the memory block which holds the core bootloader files and tells the phone what to do first.
If you hold down the recovery button it will tell the phone to boot to the recovery partition. If you hold down the download buttons it will tell the phone to boot into the download partition. If you allow the phone to boot regularly it will tell the phone to boot to the android /system partition which is where the android operating system is held
I can't explain how this works compared to windows because windows does its own thing in regarding to booting and it is not in my spectrum
The paranoidAndroid.iso file system you would try to flash for example would hold the
/system(android os)
/Data (user data and apps)
/ Or /root (main read/write accessable storage for user)
/Root would require root access to be able to get into and from there you can access the /system and /data mountpoints to modify system files, without root access you are usually not even able to view these folders
Click to expand...
Click to collapse
Yes I know Linux... but there is a HUGE difference between Embedded Linux and GNU/Linux you run on PC.....

If you were to completely wipe the phones internal memory, formatting each seperate partition into one blank one. You would need to find a way to recreate the partition table, install the bootloader onto its proper partition
Then you would use the bootloader to either recreate the partitions for the android rom, OR the ROM could self unpack and create it's needed /system, /data, and /root partitions

Related

[GUIDE] Everything Explained.

Before you go ahead and start unlocking, flashing and rooting, there are things you should know. This thread is a general guide that will serve to explain most of those things.​
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Table of Contents
A. The layers (Hardware, Firmware, Software)
B. Definitions
C. Troubleshooting Common Issues
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The Layers. How does everything come together?
Just like any other computing device there are 3 Layers to your phone. It helps to realize this prior to modifying your phone, so you are able to troubleshoot issues more effectively.
Layer 1 Hardware: The hardware layer is the physical components of your phone. That which you can touch, hold and see. This layer is the least likely to be modified unless you are a crazy super master level modder. Very few bother to mess with this layer so this layer tends to be the most stable with very little issues arising. The best way to make sure a problem is not related to the hardware layer, that is to say, a physical hardware problem where a physical component needs replacing, is to return all software and firmware to stock. This is typically done by running an RUU or manually reflashing stock firmware and software. There are instances where software or firmware modifications can affect the hardware. For example, if you overclock your CPU, the added heat could permanently damage the CPU and even other hardware components so be sure to take that into consideration.
Layer 2 Firmware: This layer is what allows the software to control the hardware in your phone, like a bridge between the two. There is firmware for just about every component of your phone, the camera, screen, radio, processor etc etc. This is the second least likely layer to be modified. S-Off is required to modify most, but not all, firmware files and rightfully so. Modifying firmware components can easily damage your phone if you do not understand what you're doing. In some cases a JTAGG repair can fix your phone from firmware modification damage, other times, only replacing physical components can repair the damage done. (Recovery and the kernel are technically part of the firmware layer but do not require S-Off to flash)
Layer 3 Software: The software layer consists of the "ROM" and applications on your phone. This is where most of the modification takes place and while modifying the software layer is the least likely to cause serious issues, it can still be dangerous. Flashing a ROM not intended for your device could easily put your phone into a bricked state. With SuperUser or Root access, software is capable of modifying the firmware layer of your device. It is up to you to decide what is safe and what's not safe. This is why rooting is not for everyone. How can you properly decide what is safe for your device without the proper knowledge?
Definitions
What is root?
Root, super user or su for short is a level of access giving you permission to read or write to folders, or partitions you could not have access to as a regular user. Think administrative access.
Consider a folder path “/sdcard/downloads/” If we break it down, “downloads” is a folder in “sdcard” and “sdcard” is one of the folders in “/” which is the “root” of the folder structure. As a regular user, one might not consider that folders other than sdcard exist in “/” as they are kind of hidden from us but rest assure they are there and this is typically where the android OS and firmware files are kept. Modifying these files can be extremely dangerous for your phone if you do not understand the modifications to the file you're making, and what steps you can take to recover from any issues you encounter.
What is an RUU?
RUU stands for ROM Update Utility. An RUU is used to reflash an existing firmware/software set or updated firmware/software set. An RUU will wipe everything and basically get your phone back to stock. Unless your phone is S-Off, you cannot run an RUU with an older firmware or software than those currently on your device. You can only run an RUU that matches your MID/CID unless you are S-Off and have SuperCID or have changed the MID/CID to match the carrier you are flashing. There may be differences in hardware/firmware between MIDs and CIDs so be mindful as this can lead to a brick. To properly run an RUU with S-On, you must also have stock recovery installed, the bootloader must be locked/relocked. BE VERY CAREFUL DOING THIS. It is not recommended to RUU or OTA after unlocking your bootloader unless you have to. If you are S-OFF you can RUU whether the bootloader is locked or not and if you are superCID, CID checks will be ignored so be sure to be mindful of the RUU you are running and that it will play nice with your phone.
What is an OTA?
OTA stands for Over The Air and implies an Over the air update distributed by your phone manufacturer, carrier or ROM developer. Unlike an RUU, an OTA will not typically wipe/factory reset your phone but can update your firmware and/or software set. To a apply a manufacturer/carrier released OTA you will need stock recovery and stock system apps installed. Your CID/MID must match that of the carrier/manufacturer your phone came from.
What is a ROM?
When the term ROM was first introduced it stood for Read Only Memory, however, most memory that claims to be Read Only nowadays is not like it was back then. Now a days it is not as complicated to write ROM as only permissions are in your way as opposed to the days when you were required to modify the hardware layer in some way to update the ROM chip. In this particular case, we are referring to the android software on your phone. Stock ROM would imply the manufacturer released ROM that came on your device when you purchased it. Custom ROMs are ROMs the are modified stock ROMs or ROMs built from android source code to. I think you get the idea. It's the device software or Operating System if you will. You should never flash a ROM that is not intended for the device you are flashing it to, this is very dangerous. Like, brick dangerous.
What is a nandroid backup?
A nandroid backup is a backup of your phone's current state. Like a snapshot or image of your phone's software. It includes the ROM currently flashed to your phone, the kernel, apps and settings. It does not include any firmware files other than the kernel and possibly the recovery. A nandroid is done with custom recovery and cannot be done with stock recovery. Taking a nandroid before you start messing with your phone is good practice. In fact, It's good practice to make nandroids before flashing a new ROM, or making any changes that may impact stability. This will ensure you always have a quick way to get back to having a usable phone. Obviously, a nandroid will not help in cases where you mess up firmware files like the radio firmware or hboot.
What is a kernel?
The kernel is the central point of an operating system. It contains the modules and settings necessary for the ROM or OS to work properly. Every Operating System has a kernel, including android. Just like ROMs there are custom kernels, with tweaks and the like that may improve or decrease performance/stability. Also, like ROMs, you should never flash a kernel not intended for your device. Very Dangerous!
What is a bootloader?
The bootloader is as the name implies, a device software/interface for handling boot operations it is contained within the hboot file. The bootloader screen has a few nifty features:
Gives you device information such as:
The bootloader state (locked, relocked or unlocked)
The Secureflag state (S-On or S-Off)
Your hboot and radio versions
Your Cid (only if you changed it)
Allows you to power down, reboot or boot your phone to android.
Allows you to factory reset your phone (Though should never really be used unless you are completely stock as you can properly factory reset in custom recovery)
Allows you access to the recovery
It gives you access to fastboot command operations you can send from your PC to your phone.
To boot to bootloader: Press and hold Power and volume up until the phone shuts off, then let go of power and volume up. Press and hold Volume down until your screen comes up in bootloader mode.
What is recovery?
Recovery is a software/User Interface that allows you to handle and make changes to your device, without having to boot the android OS. The stock M8 comes with a recovery that is quite limited but allows you to factory reset your phone and flash OTA updates which really is more than enough for the average user.
Those of us who want more from our phones, and modify them tend to flash custom recoveries with many extra features. I won't go into all the features they provide as the devs have websites, and you can visit them for more information. The two custom recoveries for the m8 include TWRP and Philz Touch. Both are very functional and choosing one is a matter of preference over anything else.
To flash a recovery image. Put the recovery image in your fastboot/adb folder and in the command prompt:
Code:
fastboot flash recovery recoveryfilename.img
You can find The latest:
TWRP for the M8 HERE
Philz Touch for the M8 HERE
To manually boot to recovery, boot to bootloader (Press and hold Power and volume up until the phone shuts off, then let go of power and volume up. Press and hold Volume down until your screen comes up in bootloader mode). Then select recovery in the bootloader menu.
What is S-Off/S-On?
This stands for Securewrite-on or Securewrite-Off. The name kind of gives some hints as to what it means. Having your bootloader unlocked, affords you the ability to to flash a custom recovery and custom roms as well as a custom kernel however, some people may need more. They may want to alter other system partitions. That is where S-Off comes in. It gives you full write access to all system partitons. It also forces a bypass for all security checks, such as those made by OTAs and RUUs, for CID and MID. S-Off is persistent. No matter if you RUU, OTA, Flash a ROM, Firmware, Factory Reset, S-Off will remain so until you use fastboot to reset the flag. I should say, if you don't know what you're doing, that is to say, if you are the type to follow instructions blindly on a thread, without much idea what is ACTUALLY Happening, what files you're modifying, you should not have S-Off. It should not concern you and that is that. S-Off can be dangerous. You have been warned.
What does a Factory Reset do?
A Factory Reset Clears the Cache, Dalvik Cache and Data Partitions. All settings will reset to default. User Apps (Apps you installed that did not com preinstalled with the ROM) will be removed. This will not restore your phone to when you purchased it. This will not relock your bootloader, Reset the S-Off flag, remove root, or downgrade your hboot. It merely affects the system and user settings and user apps.
What is fastboot?
Fastboot is a command line tool that allows you to manipulate certain parts of your phone from the bootloader. Your phone must be in fastboot mode and you must have the fastboot application and HTC drivers installed if you are on Windows. If you are on linux, the HTC driver is preinstalled.
Popular fastboot commands include:
Fatsboot devices (Lists devices connected for use with fastboot)
Fastboot flash recovery recovery.img (Flashes a recovery image)
Fastboot flash boot boot.img (Flashes a boot image)
Fastboot oem readcid (Shows the CID of the phone installed)
Fastboot oem writecid (Writes a new CID to your phone. Must be 8 Characters. Requires S-Off)
Fastboot oem rebootRUU (Puts the phone in RUU mode which is used for flashing firmwares and/or entire RUUs)
Fastboot reboot (Reboots your phone)
Fastboot reboot-bootloader (Reboots to bootloader)
Fastboot erase cache (Wipes the cache partition using fastboot. Good idea after flashing things via fastboot)
Fastboot help (Will list fastboot commands)
Fastboot boot imagefilename.img (Allows you to boot a recovery image or kernel image without actually flashing to your phone
allowing you one time access to the features without the headache of reflashing stock afterwards) Thanks to @garyd9 for suggesting I include this. Very convenient command.
What is ADB?
ADB is another command line tool used to manipulate your phone. The commands for ADB are way more extensive. ADB can only communicate with your phone while in a custom recovery or while the ROM is booted up with USB debugging turned on. The reason ADB is so much more extensive is because it allows you to remotely access your phone's terminal just like a linux terminal. You can use ADB to push or pull files to and from any partition (Some partitions will require S-Off), list devices, get a logcat, troubleshoot issues etc etc. For an extensive list of commands and how to use ADB I strongly suggest visiting http://developer.android.com/tools/help/adb.html
What is the CID?
CID stands for carrier ID. It's a string of letters and numbers, eight characters long that identify what carrier your phone is from. When you flash an OTA or RUU, The OTA or RUU checks for a few things, one of those things is the CID, to ensure you are flashing software intended for your device. Realistically, There's no hardware difference between the M8s (with the exception of CDMA vs GSM) so all firmwares/softwares should be compatible. With regards to radio firmware, your radio may function better with one firmware over another. There have been occasions with HTC where flashing an RUU or OTA with the wrong CID or SuperCID, while S-On would brick your phone. So try to be mindful of this and be careful.
Thanks to @garyd9 for suggesting I include this in my guide!
Some common CIDs include but are not limited to:
SuperCID: 11111111
HTC International: HTC__001
AT&T: CWS__001
ROGERS: ROGER001
VODAPHONE: VODAP001
T MOBILE: T-MOB010
TELESTRA: TELST001
Bell Canada: BM___001
What is a brick?
The term brick is sometimes thrown around a bit too casually. A brick is when your phone is no longer operable. It does not boot, there is no way to save it without resorting to Jtagg or replacing the nand chip or motherboard. If your phone powers on and something appears on your screen, your phone can almost always be saved. Be sure you know how to save your device before messing with your device.
Troubleshooting Common Issues
I flashed a ROM or Kernel and it's not booting! WHAT DO I DO!?
When this happens. There are actually a number of things to consider but first off, Hopefully you made a nandroid to restore from just in case the reason it doesn't boot is something not quickly or easily fixed.
1. Is the ROM you're flashing indeed intended for your device? ROMs you're flashing should be for the HTC One m8 International. You should not be flashing ROMs designed for the m8 Sprint or Verizon and should not be flashing ROMs designed for other models of phone. If the ROM you flashed is not for your device, best case scenario, it's not flashing properly. Worst case scenario, you have a brick. You will need to factory reset and wipe system then either flash a new ROM or restore a nandroid to get your phone up and running again.
2. Did you wipe Cache, Dalvik Cache, Data and System? (Don't wipe System for Kernel Install)
A factory reset will wipe all but system. You should wipe System manually in case the script for the ROM install does not do it or does it improperly. A factory reset is enough for a Kernel install. If you wiped system and just flashed a kernel, it's no doubt your phone is not booting.
* If you did not factory reset and wipe system, do so and then reflash your rom. It should then boot.
* If you wiped system to flash a kernel, you will need to reflash the rom, and then reflash your kernel again if you are flashing a custom kernel. (Note a GPE Kernel will not work on Sense and a Sense kernel will not work on GPE.
3. Did you matchup the Checksum? MD5 or SHA1 are usually posted on the ROM Download site/post. This allows you to check and make sure the integrity of the file you downloaded has been maintained. If The SHA1 or MD5 of the file you downloaded does not match what is posted, you have a corrupted file and should redownload. If you don't have a MD5 or SHA1 Checker, I suggest downloading one. Google MD5 or SHA1 Checker and you should find one. MD5 is most commonly used but it's up to the Dev as to which they post. Sometimes both. You only need to match one. (Linux comes with utilities for checking MD5/SHA1 called md5sum and/or sha1sum)
4. If you tried all these steps and it's still not booting, try another ROM. If no ROMs appear to be booting, you may be having an issue with your custom recovery. Redownload your recovery (Make sure it's the right one for your phone and check the checksum) Then reflash recovery, then use fastboot erase cache, boot to recovery and try flashing again.
5. If you tried all these and you're having issues, ask in the M8 Q&A!
I wiped everything and I don't have a ROM on my phone to flash! What do I do?
This is quite simple really.
Boot to recovery
Connect your phone to your PC
Make sure your ROM is on your PC and in your adb folder
Then use:
Code:
adb push romfilename.zip /sdcard/
Be patient, this could take a while, when it finishes you will get a confirmation with bytes in/bytes out.
Then flash.
Where can I go to find links to do all this cool stuff I want to do to my Phone!?!?!?!?
HERE!
Thank Yous!
Thanks to @garyd9
Thanks to @keithross39
This is a work in progress. I will be updating this as often as I can, trying to explain as much as I can for newer M8 owners who are not used to HTC or Android devices. If you have any suggestions for what I can put here, post here and let me know! Also, I'm not perfect, I make mistakes if I have/do make any, do not be shy! Let me know.
[08/18/2014] Partially updated and fixed spelling mistakes. More coming soon!
Hey fella, this is a good idea.
Thanks for taking the time to do this.
I am going to be getting the M8 in the near future, so reading up about the HTC specific stuff is really useful for me as I'm currently familiar with Samsung procedures and not a lot else. Most folks reading this should be familiar with the 'cross platform basics', so what you've covered so far should be enough........
But.....
Those (like me) who are getting an HTC device for the first time would probably benefit from more of a detailed description of the HTC side of things......maybe you could concentrate on expanding that information.......
Maybe you could include links to threads for s-off, rooting and/or anything else relevant?
Just my 2 cents worth....for what it's worth.....
Sent from my rooted debloated thingy
keithross39 said:
Hey fella, this is a good idea.
Thanks for taking the time to do this.
I am going to be getting the M8 in the near future, so reading up about the HTC specific stuff is really useful for me as I'm currently familiar with Samsung procedures and not a lot else. Most folks reading this should be familiar with the 'cross platform basics', so what you've covered so far should be enough........
But.....
Those (like me) who are getting an HTC device for the first time would probably benefit from more of a detailed description of the HTC side of things......maybe you could concentrate on expanding that information.......
Maybe you could include links to threads for s-off, rooting and/or anything else relevant?
Just my 2 cents worth....for what it's worth.....
Sent from my rooted debloated thingy
Click to expand...
Click to collapse
Thanks man! I welcome all suggestions! I will do my best to incorporate your suggestions
Sent from my HTC One_M8 using XDA Free mobile app
Great idea, thanks. I've been wondering what S-Off is for weeks but didn't want the flaming for asking a noob question!
Sent from my HTC One_M8 using XDA Premium 4 mobile app
Some possible additions:
What is "RUU"?
What is MID (model ID) along with a list of some common MID's
What is CID (carrier ID?) along with a list of some common CID's
How do the MID and CID relate to each other and how does the combination relate and/or interact with RUU. Related, of course, is the third part of the version number.
I was thinking of writing a guide myself, because I was so confused myself after coming from samsung, really nice.
Shebee said:
I was thinking of writing a guide myself, because I was so confused myself after coming from samsung, really nice.
Click to expand...
Click to collapse
Lol...ain't that the truth....
Sent from my rooted debloated thingy
Nice one
Very well done!
Sent from my HTC One_M8 using Tapatalk
I'm one of those who also came from Samsung (S4).
This is really great and easy to understand. This should be sticky :victory:
While I think the OP uses the term "ROM" incorrectly (Read Only Memory), I'll admit that's just me being picky. Otherwise, a very useful post... I've requested it be made sticky.
Take care
Gary
garyd9 said:
While I think the OP uses the term "ROM" incorrectly (Read Only Memory), I'll admit that's just me being picky. Otherwise, a very useful post... I've requested it be made sticky.
Take care
Gary
Click to expand...
Click to collapse
That's not being picky at all! Feel free to suggest any corrections. I welcome criticism and corrections.
Thanks for the recommendation!
Sent from my HTC One_M8 using XDA Free mobile app
exad said:
That's not being picky at all! Feel free to suggest any corrections. I welcome criticism and corrections.
Click to expand...
Click to collapse
LOL. I'm one of those people who goes nuts when people want to install "ROM's" on their phone. I keep reminding them that if it was really "Read Only Memory", that they wouldn't be able to overwrite it. Ever.
I do understand, however, that it's one of the misused terms these days. I guess it's kind of like saying you are "dialing a phone number." (There aren't any dials on our phones anymore. I haven't even seen a working rotary dial phone in years...)
Anyway - I'll stop with my OT bantering. Once I get more familiar with HTC devices I'll probably have some good suggestions for your posts.
Take care
Gary
garyd9 said:
LOL. I'm one of those people who goes nuts when people want to install "ROM's" on their phone. I keep reminding them that if it was really "Read Only Memory", that they wouldn't be able to overwrite it. Ever.
I do understand, however, that it's one of the misused terms these days. I guess it's kind of like saying you are "dialing a phone number." (There aren't any dials on our phones anymore. I haven't even seen a working rotary dial phone in years...)
Anyway - I'll stop with my OT bantering. Once I get more familiar with HTC devices I'll probably have some good suggestions for your posts.
Take care
Gary
Click to expand...
Click to collapse
Read only memory isn't a great name for it. If you've ever updated the bios on a pc, flashed a firmware update to a router, etc... you've written to read only memory. There are types that are truly read only but I can't think of a single practical example. And welcome to htc phones!
Sent from my HTC One_M8 using Tapatalk
lampel said:
Read only memory isn't a great name for it. If you've ever updated the bios on a pc, flashed a firmware update to a router, etc... you've written to read only memory. There are types that are truly read only but I can't think of a single practical example. And welcome to htc phones!
Click to expand...
Click to collapse
I'm old enough to remember (clearly) when you couldn't update the BIOS on a PC - you had to physically replace the BIOS chip. (Usually, they were socketed to make replacement a bit easier.) That was ROM. Also, early game consoles used true ROM in cartridges.
As for current practical example: a simple CDROM (not CD/RW) is, of course, read only.
I agree that it's not the best name lol but that is what it stands for....
Sent from my HTC One_M8 using XDA Free mobile app
Added this to my index thread
Hi guys! I am planning to buy an htc one m8 but can someone please tell me the different models out there? I don't want to end up buying the wrong one. Also is the dev one worth spending the extra money over the international? And is it the same model as the international one? Thanks in advance. I didn't know where else to post this. I didn't wanted to start a new thread.
Karan and all other users, please post questions in Q&A. Only things that should be posted here are suggested additions to this thread.
Also thread has been updated and more to come!
Part on RUUs is wrong...
An RUU can be run at any point and in any state (so long as you can get to the bootloader) as it completely replaces the entire system so doesn't matter if you don't have the stock recovery as it replaces it during the update process. Also, if you're S-OFF it means you can flash any RUU for any phone, handy to go between branded and unbranded software. OK, there's a risk of trying to flash an RUU from another device but if you do that you're a bit dumb!!

Android-IA or Windows/Android dual boot tablet

I have spent about a week now trying to figure out if it's possible to boot Android-IA on a 32 bit UEFI system. I have seen threads on the mailing list and other sites that apparently have gotten it working on the T100TA, but the links to their compiled roms are dead. I specifically am looking at doing this on an HP Stream 7 and making a dual boot car install. Has anyone successfully booted Android-IA on 32bit UEFI?
If this is not possible, how do the Chinese tablet manufactures do it with the same Atom chipset? I need a 7" tablet that can dual boot Android and Windows. Is there any quality model I should look for? I have seen the Cube iWork 7 which looks promising, and seems to be perfect for my needs. I will need root in Android for the car install.
I've been a lurker on these forums for a while, but just now got around to making an account. Hopefully someone here can share their experiences or suggestions. Thank you all
May be it's too late to reply, but anyway.
iWork 7 DualOS BIOS has both UEFI64 and UEFI32 booting. If you load Android(i.e. Linux), then 64bit mode is using. If you boot Windows, then 32bit mode is using.
sorg said:
May be it's too late to reply, but anyway.
iWork 7 DualOS BIOS has both UEFI64 and UEFI32 booting. If you load Android(i.e. Linux), then 64bit mode is using. If you boot Windows, then 32bit mode is using.
Click to expand...
Click to collapse
I have intel x86 based device Yoga tab 2 830LC, i used tethred twrp and made the back up of kitkat build, after some time i upgraded my system to official lollipop, but when i tried to restore to kitkat build in twrp, i am uanble to boot, and bios screen pops up, any solution will be much appreciated sir...
P.S. Sorry for posting in wrong forum, I was not able to pm you thats why i dared
Sent from my YOGA Tablet 2-830LC
QuazIqbal said:
I have intel x86 based device Yoga tab 2 830LC, i used tethred twrp and made the back up of kitkat build, after some time i upgraded my system to official lollipop, but when i tried to restore to kitkat build in twrp, i am uanble to boot, and bios screen pops up, any solution will be much appreciated sir...
P.S. Sorry for posting in wrong forum, I was not able to pm you thats why i dared
Sent from my YOGA Tablet 2-830LC
Click to expand...
Click to collapse
Probably, your backup isn't full, i.e., not all partitions are backed up. TWRP sees only standard partitions like boot, data, system. But there are many service partitions. For example, on my iWork7 there are 17(!) partitions used solely by Android.
So, i think, after downgrading you've got mess of old and new versions of partitions and they are not compatible to each other.
So, you need initial Android installer (like my iWork7 has). Contact Lenovo support.
sorg said:
Probably, your backup isn't full, i.e., not all partitions are backed up. TWRP sees only standard partitions like boot, data, system. But there are many service partitions. For example, on my iWork7 there are 17(!) partitions used solely by Android.
So, i think, after downgrading you've got mess of old and new versions of partitions and they are not compatible to each other.
So, you need initial Android installer (like my iWork7 has). Contact Lenovo support.
Click to expand...
Click to collapse
I have recovered from this mayhem, i had to flash official firmware but now I am in another difficult situation.
After updating to lollipop, I am facing a weird 'sim not ready' error, no mobile netrwork appears nor the setting of mobile network is configurable, no data(2g,3g,4g) no voice call support.
When i insert sim card it shows sim added notification, also telecom stk app shows that sim has been read,
but still I am unable to figure it out why the goddamn network doesnot shows up? Btw wifi is working nice.
Is any body also facing same issue? What causes this error?Any help to resolve this will be much appreciated.*
P.S. I am in good network and I have also tried different sim cards but no luck so far....
Sent from my YOGA Tablet 2-830LC

[Noob friendly] Basics about the G2 (bootloader, rom, etc.)

Some basics - About bootloader, kernel, recovery, rom, /system and some other partitions.
There are many noobs out there and sometimes even I am one. Two days ago @Closed Force asked me, where I know my stuff from and why things are like they are... So I finally decided to write this little guide about how Android devices basically work and what are the special things about our G2.
If you find wrong facts or any other mistakes (grammatical, language, contentwise), please bear with me. That's how I read it in the forums. And of course not everything written on XDA is correct. So please tell me by PM, or by posting in this thread if you have additions, corrections or any other concerns about this OP.
Where I got to know all this stuff? Reading, reading, reading. I first started modding my old HTC desire like 4 years ago. Since then and even before I'm reading. Mainly here on XDA but also on some german forums and wikis. It might have taken me easily 200 hours or more. So the only way to learn for a newbie (and everyone else too) is reading.
Personally I own a D802 variant. I know about some things that were different in details for the US variants, but things should be right as they are.
Finally thanks to
@d00lz for some extra research/additions and a quick read through.
@Art Vanderlay for some additions.
So let's get started:
When you press the power button, your device will load the Bootloader. The Bootloader afterwards wil load either the Recovery Image (recovery.img), the Kernel (boot.img) or the Download Mode Bootloader (laf.img), depending on the keys you press. At the moment there are three different bootloaders; The Jellybean one, the KitKat one, and the new Lollipop one. Not one of these Bootloaders can be unlocked yet, so there are workarounds which allow us to boot custom ROMs (specifically Kernels, but more about that later) and custom Recoverys. At the beginning there was the Jellybean Bootloader. The Developers (sorry, I don't know which ones) found out how to get around the locked Bootloader pretty early. They called this workaround Loki. It's intergrated into nearly every ROM except the ones which require the KitKat Bootloader (but that's usually not the reason they don't support the JellyBean one). Anyways, soon the KitKat update came and so did the new KitKat Bootloader. Sadly, LG patched the Loki exploit with this new update. However, the Developers found a new way to get the Bootloader booting files which weren't signed by LG. They called this workaround Bump. Bump basically imitates the LG signature so the bootloader thinks this file was really signed by LG. Obviously this workaround works with the JellyBean Bootloader too. In the Lollipop Bootloader this exploit has been closed and no one knows how to get around the new Bootloader, yet. In conclusion to Bootloaders, as long you have a working Bootloader, your device is not dead. You can usually recover it in some way.
The G2 has about 30 partitions (for a more detailed explanation, look here, thanks @d00lz). Each partition has its own purpose. One of them is the Recovery partition. Imagine: A Recovery partiton and a working Bootloader are everything you need to keep your phone working. It's kind of an Operating System in itself, completely independent from Android or anything else stored on your Mobile. The great thing about the Recovery partition is that it's so small that it can be run directly in the RAM. This means it's capable of modifing EVERY goddamn partition on your Mobile, including the Bootloader and the Recovery partition itself (means you can flash a new recovery.zip in your current recovery). Attention: if you are using the Recovery with a 4.4 KitKat Bootloader, it needs to be a Bumped Recovery. If it isn't bumped the Bootloader realizes that the Recovery is not genuine and generates a "Secure Boot Error".
Same thing goes for the Kernel. The Kernel is located in your /boot partition (found gzipped inside your boot.img) and is loaded by the Bootloader when you only press the Power Button and you let your Mobile boot normally. This is the reason why your Kernel also needs to be Bumped if you want to get your system booting on a KitKat Bootloader. When 4.4 KitKat came out, most Developers switched over to using LG's 4.4 KitKat sources for their projects. After a while it was realized that 4.2 JellyBean sources were a lot more reliable for AOSP baed ROMs. This is why most AOSP ROMs use the 4.2 JellyBean Bootloader and the 4.2 JellyBean Kernel sources while Stock based ROMs use the 4.4 KiKat Bootloader and 4.4 KitKat Kernel. There are different Kernels for AOSP ROMs and for Stock based ROMs. This is because Stock Kernels support some ROM functionalities that AOSP ROMs don't have, for example; Knock Code. (Note: Knock Code isn't open source, which is also another big reason why it isn't available for AOSP ROMs.) So there are huge differences between Stock and AOSP based ROMs/Kernels. The Kernel (without factoring in the AOSP and Stock issue) can be switch at anytime you want.
Now about the /data partition... All your personal stuff, including Apps, System Settings, App Data and so on will be stored there. The reason why you should clear it every time you change the ROM is that there are many variables set by the ROM you are coming from. Your current ROM may have some tweaks the new one doesn't have which means the new ROM doesn't know how to handle them which leads to crashes and instability.
Now let's get to the ROM... Having a 4.2 JellyBean Bootloader and a 4.2 JellyBean Kernel doesn't mean the top layer has to be 4.2 too. Most of the AOSP based ROMs are based on Googles KitKat or Lollipop sources. And this is true KitKat or Lollipop, with all its functionalities. Those huge version differences cause some problems in development. No wonder some things do not work properly today, but it's still the best working combination at the moment. It's kind of a wonder how it works as it is, but let's be happy with it. I'm very curious how AOSP ROMs with Lollipop Kernel sources will work. Your ROM and your entire existing Operating System is found in the /system partition. This is why it's the main partition which is modified while flashing. Which partitions will be modified and (how) is written in the updater-script file of the file you're going to flash. Theoretically, running a updater-script of a ROM which changes the Bootloader (/aboot partition) can brick your device. That's also the reason why you should only flash stuff made for your device only!
As already said an updaterscript can modify every partition through the recovery. All ROMs bring their own kernel, so you basically don't have to care about it, except you want to use a non-bumped ROM (with kernel) together with the KitKat bootloader.
Finally something about the baseband/modem (these terms are interchangeable). I noticed that the Developers or rather the Original Posters sometimes don't know which baseband the user should use with the ROM. In earlier days the wrong baseband could make the ROM bootloop. Today most ROMs work with most basebands. It's obviously best if you stay on the one you currently are on and just flash another one if something doesn't work (auto-rotation for example). The baseband can be flashed at any time and is on it's own partition.
Okay Download Mode time. It's part of the laf partition (laf.img). This partition is used by LG and it's PC software to recover the phone and bring it back to Stock. It's a partition in itself, but not completely independent of the Bootloader. It's because of this that you can of course have a fully working Bootloader, but a dead Download Mode. This means you will not be able to flash a .KDZ/.TOT file the next time you are in big trouble! ^^
Okay to wrap up I should mention the EFS partition. The EFS partition stores your device's IMEI (and the serial number as far as I know) of your device. NEVER wipe it. With a empty EFS partition you can use your mobile as a brick, ok maybe you can use it as a media tablet, but that's it (WiFi still works, @Art Vanderlay tested; see below).
Again: if you got questions/additions/correction or see a mistake, post below, or PM me, I'll edit this post...
reserved
Great post. A thread like this should be the first thread you read as soon as you enter the LGG2 sub forum.
Expect a private message soon.
Also, reserved for possible future additions .
d00lz said:
Great post. A thread like this should be the first thread you read as soon as you enter the LGG2 sub forum.
Expect a private message soon.
Also, reserved for possible future additions .
Click to expand...
Click to collapse
And you could modify your signature now^^
Sunandroid said:
And you could modify your signature now^^
Click to expand...
Click to collapse
Nice write up Sunny. You can credit Dan Rosenburg for creating loki. I can also confirm that wifi still works without modemst1 and modemst2 aka efs. My phone suffers for this thread.
@Sunandroid
Perfect! This was all I was looking for. Now I finnaly understand how my G2 works and I'll most likely not need to ask more "noob questions" in this matter.
But I would like to ask some questions because I've left with doubts after reading the OP.
As long as I have /recovery/ and /aboot/ working, I can recover my device exclusively with software. Is this right?
I've concluded that you need /aboot/ to be able to enter in /recovery/ and with recovery you can mess up with any other partition.´
How can I tell if /modem/ found here is compatible with my device? Are all /modem/ partitions the same in the same models? For example, I'm from Portugal so I have a Portuguese D802 LG G2 (if I type its IMEI in a site, it recognizes it as portuguese). If I flash a German D802 modem or English or even American, considering that they are all from D802 would they work flawlessly with my device?
Why does /modem/ cause auto-rotation to work? What exactly is /modem/?
I have a backup of all the partitions in my laptop (made via TWRP). But what happens if I accidentaly lose my /efs/ partition? Can I flash another phone's /efs/?
Rayaxe said:
@Sunandroid
Perfect! This was all I was looking for. Now I finnaly understand how my G2 works and I'll most likely not need to ask more "noob questions" in this matter.
But I would like to ask some questions because I've left with doubts after reading the OP.
As long as I have /recovery/ and /aboot/ working, I can recover my device exclusively with software. Is this right?
I've concluded that you need /aboot/ to be able to enter in /recovery/ and with recovery you can mess up with any other partition.´
How can I tell if /modem/ found here is compatible with my device? Are all /modem/ partitions the same in the same models? For example, I'm from Portugal so I have a Portuguese D802 LG G2 (if I type its IMEI in a site, it recognizes it as portuguese). If I flash a German D802 modem or English or even American, considering that they are all from D802 would they work flawlessly with my device?
Why does /modem/ cause auto-rotation to work? What exactly is /modem/?
I have a backup of all the partitions in my laptop (made via TWRP). But what happens if I accidentaly lose my /efs/ partition? Can I flash another phone's /efs/?
Click to expand...
Click to collapse
Glad I could help you this way...
about /aboot and /recovery: yes you are right. It is even better, if you have an intact laf too. That's the download mode. But as long the other two work, you can fix the laf partition easily. But if you get into the situation, that only those two are working, better don't flash a bootloader (=/aboot). If it's the wrong one your device is bricked.
Aboot is the key to your device. Everything else is fixable. At least with a little bit of knowledge and time. But better don't try it out.
No, the modems are not all the same. There are (sometimes depending on the branding) extremely small differences between the basebands/modems. I personally never had the problem, that I couldn't get any connection at all. But that's not fatal. Just flash another one and try again if it works. Btw: I once made a test in some german forums with different KK basebands. I'm not sure anymore, but the differences were minimal and I think killed my connection totally.
If you loose your efs stuff, your device is a brick with extended functionalities. The IMEI and some other data stored in the efs partition is worldwide unique. So you can't just pick the one of another phone (except the other G2 is bricked or whatever). You need the IMEI for general network connection. So it will still boot up, but you won't be able to text or call anyone with this phone.
Okay ^^
So this is a full backup of all the needed partitions right? http://prntscr.com/76edu4
Should I convert these files to something like .img to be able to flash in the phone just in case I get something that disables my TWRP access?
Rayaxe said:
Okay ^^
So this is a full backup of all the needed partitions right? http://prntscr.com/76edu4
Should I convert these files to something like .img to be able to flash in the phone just in case I get something that disables my TWRP access?
Click to expand...
Click to collapse
Yeah, I guess so. As long as you ticked everything when you backed up (with blastagators TWRP!; the official one doesn't allow to backup the efs stuff), this should be fine.
Well you could. But tbh I have no idea how to convert those files into .img files. But it isn't necessary anyways: It's unlikely that you loose the efs data on your phone unless you brick it somehow. If the phone stays recoverable, The first thing you are going to do is: flashing bootloader, laf and boot.img. Then you will go back to stock through the download mode. Once you've done this it's an easy one to install twrp again and restore the efs backup. No one is gonna flash ~32 partitions by hand. There are "easier" and more usefull ways to recover the device.
Oh and btw: no backup contains the bootloader, laf and boot (recovery developer don't implement this for some reasons). But this doesn't matter. The only thing you really need is the efs backup (which partitions exactly you can see here). Everything else isn't unique and can be extracted out of kdz files and restored this way.
Edit: the two partitions mentioned here are
Sunandroid said:
Okay Download Mode time. It's part of the laf partition (laf.img). This partition is used by LG and it's PC software to recover the phone and bring it back to Stock. It's a partition in itself, but not completely independent of the Bootloader. It's because of this that you can of course have a fully working Bootloader, but a dead Download Mode. This means you will not be able to flash a .KDZ/.TOT file the next time you are in big trouble! ^^
Click to expand...
Click to collapse
My PC doesn't install any driver when my phone is on download mode,
On recovery mode (twrp) i have MTP access but on download mode i'm not having any access,
does that mean my download mode is dead?
GoPogoOreo! said:
My PC doesn't install any driver when my phone is on download mode,
On recovery mode (twrp) i have MTP access but on download mode i'm not having any access,
does that mean my download mode is dead?
Click to expand...
Click to collapse
This has nothing to do with this thread here. The issue is different. But I have no clue what it might be... If I can elaborate a maybe working answer I'm gonna answer you in the noob thread.
Sunandroid said:
This has nothing to do with this thread here. The issue is different. But I have no clue what it might be... If I can elaborate a maybe working answer I'm gonna answer you in the noob thread.
Click to expand...
Click to collapse
Oh btw i tried your (noob friendly) no download mode, no recovery mode ..... using slax,
when i typed ls /dev/sd* it's only showed my PC (only one sda) and there is no sdb, not even one
Weirdly i can access TWRP, but i can't make any custom rom boot,
Man this is frustating
I have a phone, G2 D802 Int., which probably has a corrupt EFS partition. I guess the owner broke it flashing incompatible things into it. As a result of the corruption, ESN/IMEI is lost. It shows null. But very interestingly, the EFS partition mustn't have been wiped because by chance of a boot among a hundred, it shows up the ESN. If by chance you come across to ESN, everything operates normally. And if you reboot the phone, ESN is gone again..
I managed to make recovery work again, by upgrading the phone to lollipop. (It was another time I came across ESN.) But no download mode, USB is never identified (unkonwn usb device), USB modes cannot be changed, unless by chance you come across, USB debugging is no more either.
I was thinking to backup some necessary partitions from a working phone of the same variant, but since it's "unknown device", I cannot query it as a disk. Neither it works in Ubuntu. ls /dev/sd* doesn't show the phone. It even doesn't show the working phone.
Any idea about how I can fix the corrupted EFS partition?
pisisler said:
I have a phone, G2 D802 Int., which probably has a corrupt EFS partition. I guess the owner broke it flashing incompatible things into it. As a result of the corruption, ESN/IMEI is lost. It shows null. But very interestingly, the EFS partition mustn't have been wiped because by chance of a boot among a hundred, it shows up the ESN. If by chance you come across to ESN, everything operates normally. And if you reboot the phone, ESN is gone again..
I managed to make recovery work again, by upgrading the phone to lollipop. (It was another time I came across ESN.) But no download mode, USB is never identified (unkonwn usb device), USB modes cannot be changed, unless by chance you come across, USB debugging is no more either.
I was thinking to backup some necessary partitions from a working phone of the same variant, but since it's "unknown device", I cannot query it as a disk. Neither it works in Ubuntu. ls /dev/sd* doesn't show the phone. It even doesn't show the working phone.
Any idea about how I can fix the corrupted EFS partition?
Click to expand...
Click to collapse
I luckily never had to try it, but scroll down a bit over here: http://www.droidviews.com/how-to-backup-and-restore-lost-imei-on-lg-g2/
I wish you luck!
Sunandroid said:
I luckily never had to try it, but scroll down a bit over here: http://www.droidviews.com/how-to-backup-and-restore-lost-imei-on-lg-g2/
I wish you luck!
Click to expand...
Click to collapse
Yes I know that, but since I cannot take the device to USB debugging mode, it's not the first step I could take. "USB device descriptor is failed", this is what I get when I plug the phone.
pisisler said:
Yes I know that, but since I cannot take the device to USB debugging mode, it's not the first step I could take. "USB device descriptor is failed", this is what I get when I plug the phone.
Click to expand...
Click to collapse
So what is the current state of your phone? You have twrp installed. Can you push stuff through adb when you are in the recovery (this is pretty important, since we maybe can fix the download mode this way)? Does it boot into android?
@Sunandroid, device operates normally except the voice call & data, since these depend on IMEI. The phone boots normally, and everything is working, only the IMEI shows as "null". Additionaly, cannot enter to download mode, no recovery installed, original recovery is working, which is used to do a factory reset only. No USB debugging, it says "USB device descriptor failed". Thus no adb.
pisisler said:
@Sunandroid, device operates normally except the voice call & data, since these depend on IMEI. The phone boots normally, and everything is working, only the IMEI shows as "null". Additionaly, cannot enter to download mode, no recovery installed, original recovery is working, which is used to do a factory reset only. No USB debugging, it says "USB device descriptor failed". Thus no adb.
Click to expand...
Click to collapse
From what I've read about this issue (device descriptor...) just now, it is not software but hardware related.
I've heard of people solving that issue but I couldn't manage to do. Gave the phone to my customer back after 4 days. Importer service put the phone out of warranty and offered him a motherboard replacement for 75 $ and it's pretty fair I think. After all it comes funny when he says he's gonna file a case about returning the phone and take his money back. Well, it's up to him to end up with nothing in hands after months of waiting for a case.
Shortly, this file has been closed without a reasonable solution.
Thanks for your effort @Sunandroid.
pisisler said:
I've heard of people solving that issue but I couldn't manage to do. Gave the phone to my customer back after 4 days. Importer service put the phone out of warranty and offered him a motherboard replacement for 75 $ and it's pretty fair I think. After all it comes funny when he says he's gonna file a case about returning the phone and take his money back. Well, it's up to him to end up with nothing in hands after months of waiting for a case.
Shortly, this file has been closed without a reasonable solution.
Thanks for your effort @Sunandroid.
Click to expand...
Click to collapse
Glad to hear that. Hitting the thanks button doesn't hurt.

Newbie seeks informations

Hi.. Im new here with this device i read almost every single post here but there are quite a few things that I don't get it..
What is bootloader? Should i unlock it before rooting the device? And recovery here is in Chinese so shall i get TWRP instead? Also about the flashing Roms issue that erase imei and SN.. why would that happen? And How can i take a backup for these in case i lose them.. Some people mentioned SN writing tools but some people says its not working so im abit confused.. And has anyone noticed that the flashlight of the mobile is actually yellow that affects camera's captures? I would be really grateful if someone helps
1. What is a Bootloader?
Hboot, or we may call it Boot-loader, is like BIOS to windows. It is the first thing that runs when you boot up your Android device. It packages the instructions to boot operating system kernel and most of them are specifically designed to run their own debugging or modification environment.
Every Android phone has a boot-loader that instructs the operating system kernel to boot normally. But you need to understand one thing here that as Android OS is an open source OS and is available on a variety of different hardware, every manufacturer has their own version of bootloader specific for the hardware present in it’s environment.
2. Should you unlock it before rooting the device?
It solely depends on you whether you want to unlock it or not. Unlocking bootloader will give you access to installing custom recoveries on your phone and also you can use custom kernels to boost up phone's performance or simply get more battery juice. Since our K4 note doesn't have any custom kernels so good luck with that.
Warning: Unlocking Boot-loader voids phone's warranty​
3. Why does IMEI/SN erases while flashing ROM's
People don't read the tutorial properly. They blame the OP instead when they do something wrong and loose their IMEI/SN.
What basically happens is, when flashing ROM's through SP flash tools, They should flash it in "DOWNLOAD" mode only and not in "Format ALL" mode. People who all lost their IMEI basically did this mistake.
4. How to Backup and Restore your IMEI/SN (NVRAM)
All the device specific details such as IMEI, SN, MAC addresses are stored in a partition called as NVRAM. So backing it up will indirectly be referring to backing up your IMEI/SN. Here is how you can do it.. LINK
5. How to install Recovery?
if you are on Marshmallow then you will be able to install recovery through this thread. LINK
6. Yellow Flashilight problem?
This bug is introduced in Android V6.0 that is marshmallow. Actually this is not truly a bug. Unlike on Lollipop which had only one LED light enabled during Camera operations, Lenovo decided to enable both of the LED's (That is white and yellow) to give the images a more true LIVELY appeal.
But terming this as bug here because nobody liked it and users were pissed off straightaway. Hopefully, Lenovo will fix it soon.
Hit Thanks if i helped..​
Krishnas096 said:
1. What is a Bootloader?
Hboot, or we may call it Boot-loader, is like BIOS to windows. It is the first thing that runs when you boot up your Android device. It packages the instructions to boot operating system kernel and most of them are specifically designed to run their own debugging or modification environment.
Every Android phone has a boot-loader that instructs the operating system kernel to boot normally. But you need to understand one thing here that as Android OS is an open source OS and is available on a variety of different hardware, every manufacturer has their own version of bootloader specific for the hardware present in it’s environment.
2. Should you unlock it before rooting the device?
It solely depends on you whether you want to unlock it or not. Unlocking bootloader will give you access to installing custom recoveries on your phone and also you can use custom kernels to boost up phone's performance or simply get more battery juice. Since our K4 note doesn't have any custom kernels so good luck with that.
Warning: Unlocking Boot-loader voids phone's warranty​
3. Why does IMEI/SN erases while flashing ROM's
People don't read the tutorial properly. They blame the OP instead when they do something wrong and loose their IMEI/SN.
What basically happens is, when flashing ROM's through SP flash tools, They should flash it in "DOWNLOAD" mode only and not in "Format ALL" mode. People who all lost their IMEI basically did this mistake.
4. How to Backup and Restore your IMEI/SN (NVRAM)
All the device specific details such as IMEI, SN, MAC addresses are stored in a partition called as NVRAM. So backing it up will indirectly be referring to backing up your IMEI/SN. Here is how you can do it.. LINK
5. How to install Recovery?
if you are on Marshmallow then you will be able to install recovery through this thread. LINK
6. Yellow Flashilight problem?
This bug is introduced in Android V6.0 that is marshmallow. Actually this is not truly a bug. Unlike on Lollipop which had only one LED light enabled during Camera operations, Lenovo decided to enable both of the LED's (That is white and yellow) to give the images a more true LIVELY appeal.
But terming this as bug here because nobody liked it and users were pissed off straightaway. Hopefully, Lenovo will fix it soon.
Hit Thanks if i helped..​
Click to expand...
Click to collapse
Ahaaaaa Thanks Alot now it get it all.. Hope they fix that soon.. And i read that some devs here is willing to make a custom kernel i guess.. thanks again and sorry for wasting ur time.. Btw have u noticed that the sound on headset and Bluetooth is also abit lower than other devices?
Lenovo A7010 - CM13.0 Android 6.0 on lenovo-forums.ru

Android to Windows Hack or Dual boot Option?

So im thinking of purchasing one of these when the come out here and i was wondering about an android to windows os hack. Will there be one in the immediate future and will dual booting be an option?
The hardware is exactly the same.
There must be a way to dual boot, hopefully others on this forum can figure out how to do this if Lenovo doesn't facilitate dual boot themselves
Best
I believe there's a different BIOS for Win vs Android. Could have sworn I saw the Windows BIOS posted on the Lenovo support site prior to the Oct 17 launch. It seems gone now though, unless I'm missing something or went to the wrong link? Unlikely you can install Win without a different BIOS.
There is some clear hardware differences with the Android and Windows tablets. Specifically, 2 different physical layouts for the halo keyboard, where the windows one has defined left and right mouse click buttons. There doesn't seem to be any way of accessing the BIOS on the Android tablet, and it does have the usual Android power + volume up, power + volume down recovery options, so it looks like it boot directly to the boot loader.
The Bios is still there ... but how would you flash it?
http://support.lenovo.com/de/de/products/Tablets/Yoga-Series/YOGA-Book/downloads/DS119182
ok so there is also android open source code available in their site, any chance of making a custom rom?
I wonder if we could flash the Chuwi 12 roms onto this given that Chuwi12 has dual boot already?
This is reallly really stupid to me, why not provide dual boot in the first place? I would not mind shelling out $100 more for a dual boot version. Now if I want the windows version I will need to spend another $550 to get another OS with the same device. I will end up having 2 same devices, but that is so anti-mobile really. Do I have to carry 2 hardware devices so i can have 2 OSes at the same time?
Lenovo get some grip please and provide a dual OS version.
win 10 driver
Today, the windos 10 drivers are online..
The drivers you get with levono support with input of the serial number
It must now be possible to build a dual system
Tastertur chipset audio and more .
igelelf said:
Today, the windos 10 drivers are online..
The drivers you get with levono support with input of the serial number
It must now be possible to build a dual system
Tastertur chipset audio and more .
Click to expand...
Click to collapse
Could you post the link for the windows 10 drivers? also any idea on how to unlock the bootloader?
Hi,
earthCallingAngela did unlock the bootlader. .
My background knowledge about booting is very low. But I think there are huge differences between Android and Windows. I think If a system can boot via PC-Bios or Android-Boot-Loader is "on the chip". If this is correct you would need a Android-Boot-Loader that does boot into a windows ... IMO this is no "easy to do". May be the guys who did create Remix OS found a way to do that ...?
Can we use Chuwi 12's disk image somehow? It comes with dual boot.
hajkan said:
Can we use Chuwi 12's disk image somehow? It comes with dual boot.
Click to expand...
Click to collapse
Are the two the same hardware? My understanding is that unless the hardware is very similar, you can't use other ROMs without a *TON* of work.
so i was able to install android x86 6.0 on my yoga book, unfortunately i managed to do it over my windows install so now i just need to reinstall windows lol.....
---------- Post added at 06:35 PM ---------- Previous post was at 05:54 PM ----------
decided to install 7.0 over my 6.0 install i just made and messed everything up. now im back to just trying to get gparted to run so i can reformat and start over.
bisharat said:
Could you post the link for the windows 10 drivers? also any idea on how to unlock the bootloader?
Click to expand...
Click to collapse
http://support.lenovo.com/kr/en/pro... and Software|Drivers and Software&beta=false
you can download yogabook win10(64bit) driver here.
edited--
you should change operating system dropdown menu from android to windows10
Hi & Happy New Year
Now it's possible to get root with android version
I have a YogaBook with Windows version ; Someone can make a backup Android version?
Maybe it's possible to create a dual boot with the windows version I cross the fingers :fingers-crossed:
Where and how?
ThomasHardy said:
Hi & Happy New Year
Now it's possible to get root with android version
Click to expand...
Click to collapse
someone can said me, where i found an android image? (original yoga book, of course) i try to install Remix OS and Android-x86 6.0-r1 released from Android-x86.org but, its can't run. graphics issues and reboot.
i install in a MicroSD and boot it booting yogabook hold volume up + power boton and select boot menu, but it fail on boot.
i have yoga book windows. any idea?
thanks
sorry for my english..
I'm exploring this as well.
Since the BIOS and drivers available (just tested with my serial#), it does seem like it would be relatively easy to dual-boot, provided you can get past the loader issue.
I've done many dual-boot setups, just not since the Win7 days, with the Win8 and forward it's gotten quite a bit trickier, the loader does a bunch of "extra" stuff, boot timing and such, to protect itself.
I've also never done an Android/Windows dual-boot, mostly just Win/Win or Win/Unix.
I think you'd have to figure out how to bootstrap these, so the custom loader can take over, and load from there, but this is a bit beyond my Android capabilities.
Has anyone even tried this? I assume the power/volume keys must work, to get at the loader?
Hi there !
I've just unlocked my Yoga Book's android bootloader and made a backup. I'm trying to install Windows 10 and replace Android with it. The problem is that I don't know how to boot the device from the USB drive.
Does anyone know how to do that ? Even if rooting is required ?
P.S. : I can't google it as all results link to "how to boot a PC from android device", which is the reverse...
Totjoss said:
Hi there !
I've just unlocked my Yoga Book's android bootloader and made a backup. I'm trying to install Windows 10 and replace Android with it. The problem is that I don't know how to boot the device from the USB drive.
Does anyone know how to do that ? Even if rooting is required ?
P.S. : I can't google it as all results link to "how to boot a PC from android device", which is the reverse...
Click to expand...
Click to collapse
simple...you can't do that! it's not possible to boot usb from android bootloader or recovery.

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