Rooting an old Samsung Galaxy SII

DoaM

esuhl wrote: »

I'm baffled (again!)... Any ideas...?

Use CWM if you're installing a CWM recovery, and TWRP if you're installing a TWRP recovery?

esuhl

DoaM wrote: »

Use CWM if you're installing a CWM recovery, and TWRP if you're installing a TWRP recovery?

Uh... I'm confused. I thought CWM and TWRP were recoveries.

I don't fully understand IsoRec, but I the video guide implies that I need an IsoRec-enabled version of TWRP to install Lanchon-repit.

But installing IsoRec_TWRP doesn't do anything. I'm doing this via the "install from zip" option in CWM...

Do I need to install bog-standard non-IsoRec TWRP before IsoRec_TWRP?

esuhl

I think it's the fact that my phone shares a single kernel between the recovery and OS (if I've got that right), which is confusing me.

This is what it says on the TWRP site:

NOTE: The i9100 does not support a separately bootable recovery partition. To install and use TWRP, you will need to install a custom kernel or boot image that supports IsoRec.

I suppose I don't really understand the partition layout, or the Android boot process... I thought the kernel was part of the OS firmware image... so how can I install a custom kernel without installing a new OS... Where is the kernel -- on the boot partition? There must be a simple guide that explains all this, but I can't find one.

I've read so much in the last few days my brain hurts! I can't understand why it's so complicated! I feel like I must be missing something obvious... :-/

esuhl

I found another guide here:
https://zorruno.com/2016/upgrading-a-5-year-old-samsung-galaxy-s2-to-android-m/

This suggests that all later versions of TWRP are IsoRec compatible. And that you can install TWRP by doing this (from a PC) in recovery mode:

adb root
adb push twrp-3.0.2-0-i9100.img /dev/block/mmcblk0p6

It seemed to work fine... but on rebooting into recovery CMW loads instead of TWRP!!! AAAAAAAAARGH!

---

So I tried following the instructions on the TWRP site:
https://twrp.me/devices/samsunggalaxys2i9100.html

The guide ends with:

The image will get flashed in '/dev/block/mmcblk0p6' partition under mountpoint '/recovery'
Device will automatically restart when flashing is complete

The flash process completes, but the phone doesn't reboot. When I reboot manually, CWM recovery starts again.


Help!!!

JJ_Egan

You may find Philz Recovery is easier to flash .

A custom kernel can be flashed to the OS/ Firmware as can in many cases modem bootloader CSC .Flash is as a zip via recovery or as a tar file via Odin .

esuhl

JJ_Egan wrote: »

You may find Philz Recovery is easier to flash .

I had a quick look, but I think it's just a modded version of CWM.

JJ_Egan wrote: »

A custom kernel can be flashed to the OS/ Firmware as can in many cases modem bootloader CSC .Flash is as a zip via recovery or as a tar file via Odin .

What's a "modem bootloader CSC"?

This is really doing my head in. I thought I'd just give up and install the stock firmware again. I have the following ROM files, either of which seems suitable:

• GT-I9100_VOD_1_20131209181510_ayd7npl7nz.zip
• VOD-I9100XWMS2-20140128180739.zip

I unzipped one and reflashed the phone using the following Heimdall command:

heimdall flash --SBL1 Sbl.bin --PARAM param.lfs --KERNEL zImage --CACHE cache.img --MODEM modem.bin --FACTORYFS factoryfs.img --HIDDEN hidden.img --verbose --no-reboot

Everything seemed to complete successfully, but when I boot up the phone, I just get the message, "Enter password to use encrypted device storage".

I don't understand. I've never encrypted anything on the phone. I tried again with the other ROM file, but exactly the same thing happens.

Am I doing something wrong?

EDIT: I rebooted into recovery and... Cyanogenmod recovery started. A factory reset got rid of the "encrypted device storage" message. But now the phone boots into Cyanogenmod.

Do I need to flash the recovery partition with a separate stock image?

JJ_Egan

Yes Philz is CWM .
Modem = radio for network connection .
Bootloader same as PC loads the OS .
CSC individual customer specifications basically network settings .

Is the tar file you flash through Odin inside the zip ??

You flash the stock firmware to get rid of CM .

jshm2

Don't waste time rooting just for app permission control. Samsung have released quite a few updates for older phones of late. Try a software update first.

As for app permissions without rooting. You can use App Package Disabler 1.1.4 or S Package Disabler for Samsung Pro v1.2 to do that WITHOUT rooting.

esuhl

JJ_Egan wrote: »

Yes Philz is CWM .
Modem = radio for network connection .
Bootloader same as PC loads the OS .
CSC individual customer specifications basically network settings .

Ah, right. Thanks. :-)

JJ_Egan wrote: »

Is the tar file you flash through Odin inside the zip ??

I was using Helmdall rather than Odin. But yes, the .tar.md5 file was inside the zip. I then untarred that (apparently .tar.md5 files are just renamed .tars) to get the files needed for the Heimdall command above:

sbl.bin
param.lfs
zImage
cache.img
modem.bin
factoryfs.img
hidden.img

JJ_Egan wrote: »

You flash the stock firmware to get rid of CM .

If only I knew how! Argh! As well as the Heimdall command above, I tried installing CWM, then using the "install from zip" to reinstall the firmware, but I just get the message "Installation aborted."

jshm2 wrote: »

Don't waste time rooting just for app permission control. Samsung have released quite a few updates for older phones of late. Try a software update first.

Now you tell me! :rotfl:

Alas, I've already started butchering the filesystem and I don't seem to be able to get the stock firmware reinstalled...

I should have just checked for updates first! But still... I'm not usually defeated by technology so easily. Now I won't be happy until I have completely hacked and tweaked its insides out!

JJ_Egan

Odin flashes the full tar file you do not untar , don't know if Heimdall is different .