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[KERNEL]DualBoot - Devil4.2 (04-Feb-2013)

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By DerTeufel1980, Recognized Developer on 15th January 2013, 08:22 PM
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Attention! Before installing this kernel, read carefully (don't forget reading post 2!)!

1.) Make a Nandroid!
2.) If you are installing this kernel the first time, it wipes your data and system! (this is caused by creating the secondary system partition) - you can restore your nandroid afterwards
3.) Make sure to have 700 mb free space at your internal sdcard (this is needed for secondary data)
4.) You can't install a rom as secondary rom, without doing some work yourself! This is caused by the way, rom installing is mounting the system partition. I can't do anything against it (What you need to do is written in the guide of post 2)
5.) You only can install 4.2.1 roms, with the "default"/cm partition layout!
6.) You have to install the kernel again, after you have installed a new rom. If you forget to install it, you just boot up to primary rom.

Many thanks to:

- cm team, especially pawitp
- stratosk
- mialwe
- zachariasmaladroid
- kasper_h
- krarvind
- kufikugel
- gokhanmoral (great idea to build a dualboot kernel, always helpful)
- Bejda
- sUsH667 ( i have taken his design for aroma filemanager, it's looking great)
- amarullz ( who coded the filemanager)
- ...
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15th January 2013, 08:22 PM |#2  
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About this kernel (and installing it):

installing a dualboot kernel the first time:
1.) the kernel needs to create a secondary system partiton. this is taking place at the current /data partition.
b) the new version (04-Feb.) is creating an addional "devil" partition of 20 mb. it currently isn't used, but i am preparing already for later (boot.img is limited to 7.5 mb in size because of the boot partition size), because the dualboot kernel needs to include more files as the stock one, and for 4.1.2 support, i even need to include more...
2.) by installing the kernel the first time, data and system get deleted due to the partition change.
3.) as a security feature, the install fails the first time, before your data gets formated. if your install fails, you still can make a nandroid, if you didn't before. then just install again. this time the install does not fail. the kernel reboots to recovery automatically now
4.) install the kernel a third time
5.) before installing a new rom, go to advancend, reboot recovery
6.) after installing a rom (primary or secondary), flash the kernel again, follow the steps below for this!

updating the dual boot kernel to a newer version/installing the kernel after a rom flash:
1.) flash the kernel
2.) reboot to recovery (just in case...)

how to revert the partition changes:
there also is a "revert" kernel now, which is available here:

if one isn't using the dualboot kernel, the "revert" kernel doesn't revert anything, but is a normal single boot kernel, with the same features as the dualboot one.

if one is flashing reset kernel after dualboot, you need to flash it three times. the first install just fails. the second one succeds and reboots to recovery. the third one finishes the restore.
The reset kernel wipes data and system, (only) if coming from dualboot kernel!

in the recovery:
1.) by default, there is no entry for system and data in the fstab. i have done this, to ensure you don't install apps/packages to the wrong rom. this means, if you just go to install zip, install fails, because there is no system partition which can be mounted.
2.) the dualboot menu. what do these options do?
a) the first two options are mounting primary/secondary filesystem right after clicking.
b) these two options are preparing for mounting primary/secondary filesystem after you reboot to recovery. without using this, you don't have the options in recovery, to mount/format data or system, etc
3.) reboot primary/secondary system should be clear

how to install a rom as primary/secondary rom:
1a ) remove spaces from filename!
1b )install zip from sdcard
2.) choose from where to install
3.) choose what and where to install
note: the kernel installs itself after the rom. no need to reflash. this does not work with elite rom (because of the zip design)

How to create/restore a nandroid:
1.) go to dual boot menu
2.) select "enable mounting of pri. fs" or select "enable mounting of sec. fs"
3.) reboot to recovery
4.) backup or restore your nandroid, depending on your previous choise, you'll backup/restore the primary or secondary system
5.) consider to rename your backup, to something like primary_date or secondary_date

here you get the kernel. nothing else needed:
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15th January 2013, 08:25 PM |#3  
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Going to try it out

Enviado desde mi GT-I9000 usando Tapatalk 2
15th January 2013, 08:34 PM |#4  
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Where is the link

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15th January 2013, 09:01 PM |#5  
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WOW great work derteufel

thanks a lot
15th January 2013, 09:01 PM |#6  
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WOW... Just wow!
15th January 2013, 09:20 PM |#7  
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almost all files uploaded/added now

a dualboot version of hellybean is currently uploading
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15th January 2013, 09:23 PM |#8  
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thanks dev

will give it a try ! ...
15th January 2013, 09:28 PM |#9  
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will you compile a kernel without dualboot for JB4.2.1???

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15th January 2013, 09:28 PM |#10  
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Awesome. Cant wait to try this. I remember a long time ago i mentioned it in your kernel thread.

Still following your work actually, but got stuck on CM all this time. Now can be on both! Nice.

So how does one boot into 1st or 2nd rom? By button combo? Dont see it mentioned.

Considering second donation :thumbup:
15th January 2013, 09:34 PM |#11  
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WOW WOW WOW WOW !!! DUAL BOOT ON OUR GALAXY S!!! FANTASTIC!!!! someone tested it???

sorry for my bad english
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