Related
So, let's get linux installed natively on our Iconia.
As some of you I have been working on porting Iconia to chromeos 2.6.38 kernel (to get rid of Acer crappy moron-written drivers (well.. nothing personal, but most code written for commercial embedded devices is a pile of crap and you have to rewrite everything to update kernel or integrate upstream))
For now, I have hardcoded the kernel command line in the boot config to boot off /dev/mmcblk1p2 (that is, you must create ext4 (this is also hardcoded.. uhh)) second primary partition on your sd card with the root fs). For now, until all hardware is working fine and userland is ready, let's boot off micro sd. We don't have nvflash yet so let's leave repartitioning internal storage aside.
Flash the kernel image instead of boot.img to LNX or instead of recovery to SOS. And make sure to write your UID in a secure place before messing with the device - this is the only way to flash your device if you have checksum errors (you should contact sc2k in that case). Okay, even if you eff up here, there is still a way to get UID from a brick so take it easy. But if you do screw it, be prepared to work hard and use some command-line tools.
You should be able to use any armel rootfs. For X11, use fbdev driver and evdev for touchscreen.
For the proprietary NVIDIA accellerated drivers for X11, OpenGL ES and OpenMAX, download the nvidia-tegra package from AC100 PPA https://launchpad.net/~ac100/+archive/ppa (probably you have to manually download using this link http://ppa.launchpad.net/ac100/ppa/...dia-tegra_12-0ubuntu1~alpha1monson6_armel.deb as the package didn't show in aptitude for me after adding to sources.list.. or i was doing sth wrong) or the tarball from nvidia. A newer package of tegra drivers is available at https://launchpad.net/ubuntu/+source/nvidia-graphics-drivers-tegra. You may just add an alternative to mesa EGL/GLES library path via update-alternatives to always use nvidia libs.
precompiled kernel image [15 August 2012]
http://www.mediafire.com/?p32l949n2s7la43
xorg.conf
http://pastebin.com/0a6T6c18
Here is some video
http://www.youtube.com/watch?v=NlGHZ5VTAr8
And now - we need developers, developers, developers.
The git is https://github.com/astarasikov/iconia-gnu-kernel
The main branch is chromeos-2.6.38 that is more stable. The 3.0 branch is unstable (network traffic causes virtual memory trashing).
For now, the following stuff works
-Panel/framebuffer/backlight
-Touchscreen
-Internal eMMC
-microSD slot
-usb gadget
-usb host
-gpio keys/buttons [rotation switch acts as wifi/bluetooth power blocker. iirc, left position disables wireless, right - enables]
-charger
-battery
-shutdown
-LEDs
-bcm4329 wifi (don't forget to copy bcm4329-fullmac-4.bin to /lib/firmware/brcm and nvram.txt from android's /system/etc to the same dir as bcm4329-fullmac-4.txt) [causes lockups with 3.0 kernel]
-nct1008 temperature sensor for cpu throttling
-sound. external speakers and headphones.
-bcm4329 bluetooth. accessible at 115200 on /dev/ttyHS2. Look at http://htc-linux.org/wiki/index.php?title=Ubuntu/Leo/Bluetooth to get it running at higher speeds with proprietary firmware patches (hcd files from android)
-suspend. Although will probably drain a bit more power than android because mmc power is not disabled (due to a race condition in kernel. and because we have rootfs on micro sd). Two glitches are: sometimes, the device freezes for several seconds after suspend (will test later if playing with wifi clock fixes it) and fonts get corrupted after suspend if using proprietary nvidia X11 driver. [suspend works in 2.6.38 only]
-kxtf9 accelerometer
-mpu3050 gyroscope
-ak8975 magnetometer
The following stuff is broken or not implemented at all
-hdmi video. May be working but no one has tested. hdmi audio is not implemented.
-light sensor
-video cameras, focus, torch.
-gps. To turn on the chip, it should be enough to enable gpio 203 via sysfs. Unfortunately it uses the proprietary MEIF protocol which can probably be obtained from Nokia under NDA. And I don't feel like disassembling the whole megabyte of the gps daemon
-3G. I don't have the modem in my iconia. So I don't care. But should be easy to add.
And one notice for those who want to join in. I don't care if hardware works properly. I want 'beautiful' code. That is, please, when you make patches to add functionality, do not follow the path of corporate coders and do not invent custom interfaces and sysfs hacks. Use rfkill for bt/3g power control, for example. And don't be selfish - please share your patches and userland stuff.
TODO:
-fix framebuffer issues (no console till X boots, X fonts and window decorations get corrupted after suspend with proprietary drivers) it kinda works.
-video camera
-port meego or build the list of good software in ubuntu for handling sensors, virtual keyboard etc
I'm not currently working on the project and don't have the device anymore. Feel free to PM me if you need help with some tegra hackery
good job...
Hi sp3dev,
Cooooool, you rock
Thanks
FANTASTIC WORK!!!!
Guys... I'm not so clued up on the bootloader here, but is dual boot possible with this setup?
"so I guess I need to switch distro to try out this cool stuff"
What distro are you considering switching to?
tholmewood said:
FANTASTIC WORK!!!!
Guys... I'm not so clued up on the bootloader here, but is dual boot possible with this setup?
"so I guess I need to switch distro to try out this cool stuff"
What distro are you considering switching to?
Click to expand...
Click to collapse
Yes, dual boot is possible - the android is in internal memory, our stuff is on micro sd card. It should be possible to even dual boot from internal memory, but not right now
I am switching to ubuntu because it has a lot of packages prebuilt
sp3dev said:
Yes, dual boot is possible - the android is in internal memory, our stuff is on micro sd card. It should be possible to even dual boot from internal memory, but not right now
I am switching to ubuntu because it has a lot of packages prebuilt
Click to expand...
Click to collapse
Man I cant wait to get Netbook Remix dual booting on this badboy... Living the dream I tell ya...
Thanks again
Would booting a distro from say the usb work?
Sent from my HTC HD2 using XDA Premium App
M..N said:
Would booting a distro from say the usb work?
Sent from my HTC HD2 using XDA Premium App
Click to expand...
Click to collapse
I see no reason why not. But you'd have to hardcode the uuid of the boot partition in kernel command line or build a ram disk. Anyway having to use a heavy and power consuming external storage sounds like an extremely stupid and useless idea
what about Gentoo?
This is great! i would love a dual boot. and ubuntu! i just got done reading that the asus got this and was like. i want it now. now we almost have it keep up the great work!
sp3dev said:
I see no reason why not. But you'd have to hardcode the uuid of the boot partition in kernel command line or build a ram disk. Anyway having to use a heavy and power consuming external storage sounds like an extremely stupid and useless idea
Click to expand...
Click to collapse
Not even from a USB flash drive? Wouldn't it be the same as say booting it from a microsd card?
Sent from my A500 using XDA Premium App
Have Anyone seen this LINK?
Hope it can help!
OrionBG said:
Have Anyone seen this LINK?
Hope it can help!
Click to expand...
Click to collapse
That sounds like the place to start!
Thanks
Thanks man you really rock !
I cant wait to try it out. Hope you will continue working onto this.
can you share the steps after compiling the kernel ?
I would like to try with different kernels but I'm still not confident on how to do this.
If I use dd if=zImage of=/dev/mmcblk00p1
will this effectively boot this kernel after pressing power and vol- keys ?
Hello, do you think that Dvb t is possible if Linux is running on the acer?
yodor said:
can you share the steps after compiling the kernel ?
I would like to try with different kernels but I'm still not confident on how to do this.
If I use dd if=zImage of=/dev/mmcblk00p1
will this effectively boot this kernel after pressing power and vol- keys ?
Click to expand...
Click to collapse
No.. You need to build boot image with android's mkbootimg and flash instead of recovery. And then, mkfs.ext4 on your sd card on partition mmcblk1p2 and untar rootfs there
Thanks man, this is really getting clear to me now.
I'm going to try and post results here. I will love to try and see how arch, fedora and ubuntu will run on A500.
http://dev.gentoo.org/~armin76/arm/tegra2/install.xml
There are two apps in the Android market that will install either Ubuntu or Backtrack for you- they are not native installs though I can confirm they perform well even if it is chroot and I can also confirm they work on the iconia great! Search ubuntu installer or backtrsck5 linux install in the mmarket....
If you ever used CWM, CWMT or other non factory recoveries to wipe your data, you probably noticed that you lost the ability to encrypt your phone. Or maybe you did not even realize this is why encryption does not work.
For the Android phone encryption to work, it needs the /data (usrdata) partition to have a little bit of unused space between the end of the filesystem and the end of the partition. And as soon as you use CWM to wipe, it actually reformats using all space, and encryption does not work anymore.
User lolo250612 brought this to my attention, and together we created a update.zip that shrinks the /data filesystem by 1MB
In fact, we created 2 patches: One to shrink, and one to first repair the filesystem. The first will refuse to shrink if the file system is not clean and healthy. They will automatically find the correct usrdata partition device and its size. The shrink will then resize to 1MB less then the partition size (which means it could also be used to grow if you somehow had a filesystem a lot smaller, for example because you restored an smaller image from somewhere).
Both patches are created with statically linked e2fsprogs binaries and its own static copy of busybox shell interpreter. So they should work on all Android devices that use ext file system (probably all V2.3.1 Gingerbread and higher androids), and you should not lose any data because of this. But it is always good to make a backup.
We tested this on 2 phones, both ICS phones, and with both CWM and TWRP type recoveries, and are fairly certain it is safe to use. But to repeat, you should always take a backup of your phone.
Both patches can be found on my shared drive:
ICS_usrdata_fix-fs.zip
ICS_usrdata_shrink.zip
Procedure:
- Make backup of your phone
- Place files on SD card
- Boot into recovery
- Apply the shrink update
- If it tells you the filesystem is damaged apply the fix-fs update first
The patch only shrinks the filesystem, nothing is actually installed or removed on the phone. But if you use encryption, you could leave this patch on your SD card so that every time you wipe data, you can run the shrink patch again afterward to enable encryption again.
If you do use this, please report back in this thread, possibly mentioning your phone model and ROM you are using.
Quick encryption guide (and more)
I won't go deep into useless details as everything has already been described about Android phone protection somewhere on the internet. I will just give some meaningful links and tips by illustrating how I have protected my phone. Really nothing new or innovative, just a compilation of a few hints that I have put in practice to protect the numerous pieces of information that are on my phone.
Step 0: awareness
----------------------------
Why bother with phone security?
In short, I am clearly paranoid. Well, in fact, I don’t really feel at ease when I know all the information, both personal and professional I have on my phone. Over the month, my Androphone has become a real digital Swiss-knife and personal secretary. This includes:
Personal and professional contacts
Personal and professional agendas
Personal and professional digital exchanges (SMS and email)
Personal and professional photos
Banking account information
Trails where I run
Etc… etc…
Don't want someone looks at them. Not you?
Fist step: on-line protection
----------------------------------------
The first step in protecting your data consists in making hard to access indirectly the data that lay on your phone memory. This access consists in using the system when the phone is on, either via the GUI and the phone controls, or remotely (essentially by network connections, or phone basic functionalities like sms). So, basically, you need to lock efficiently your phone from preventing someone else to unlock the user interface that allows interactions with the system, and protect all communication channels.
To lock efficiently your phone, you must use a pin code of at least 4 digits (6 is better) or a pass-phrase. The latter is much less practical without improving online security that much. Above all, you must avoid those silly locking solutions like face recognition unlocking, or pattern lock. Those are toys for naive young boys. Not for those concerned seriously by security.
For protecting remote access to your phone, I would suggest:
1) Double check that USB debugging is disabled. This a major security hole.
2) Turn on data connections (bluetooth, wifi and 2/G/3G/4G) only when required (email checking, web-surfing session, data synchronising), and off rest of the time.
3) Avoid install cracked unofficial apks, or applications that asks for permission far beyond their obvious and principal utility
4) Install a software security app, if possible, open source and recognised by xda members. Once an adept of Droiwall, I have switched to Avast mobile security because of its extra features. But it is not opensource and it is a question of taste. But do this carefully, see that for instance before making a choice: http://download.cnet.com/8301-2007_4-57391170-12/dont-get-faked-by-android-antivirus-apps/ and http://www.av-test.org/fileadmin/pdf/avtest_2012-02_android_anti-malware_report_english.pdf.
But, you must be rooted (which is in itself a security hole if not mastered) and one must have a kernel with netfilter functionalities activated. This is the case with the stock kernel of the phone I use at the present time (Lenovo A789). But was not the case of 2 Samsung phones I used before. You have to either install a custom kernel adapted to your phone, or make your own if you have access to its sources (see tutorials as: http://forum.xda-developers.com/showpost.php?p=22941057&postcount=1)
5) Personally, I would feel more at ease if I could find an easy to use firewall solution that could close, and better, make stealth all the local ports of my phone, especially when I am not behind a wifi router. But I haven’t found one yet. Droidwall, nor Avast, addresses this functionality, whereas it would be fairly easy to implement it with the netfilter system layer underneath.
Second step: offline protection
-------------------------------------------
Here we are. Now your phone is protected when it is on. But, what if you switch it off, or remove its sdcard? The data lay on the internal memory, unprotected (at best obfuscated). Really easy to find a custom recovery for almost all phones, write a script to dump /data on a sdcard and then make whatever you want with the copy.
Don’t like that? The only solution to prevent /data from being read by someone else is to encrypt the /data partition. To do that, your phone or tablet internal storage partitions must be seen by your system as block devices. This is the case with eMMC but not with Yaffs. So beware, if you want encryption you need to buy a device that answers this requirement. This is not always true and almost never documented. Notes on the implementation of Android encryption are there: http://source.android.com/tech/encryption/android_crypto_implementation.html
Now, as me, if you are reading these lines, you are certainly looking for extra information about your Android device and probably extra functionalities.
Certainly, the most frequent way to install extra functionalities and custom ROMs to your phone is to use an update zip file. With stock recovery, this zip file needs to be signed, otherwise it is rejected. For maximum flexibility and ease of use, alternative boot recovery have been developed, of which CWRP is certainly the most famous.
Usually, for 99% of users and operations, CWRP operates great. Sometimes, as nothing is perfect, a bug may occur. This is the case for built in ICS encryption process. As Cybermaus indicates in the first post, to be able to perform this encryption the /data filesystem must be slightly smaller than the underlying partition. But CWRP, at least up to the version 5.5, formats all the corresponding partition leaving no place for Android to store the required information to be able to start the encryption process. This is clearly described in the following links: http://forum.xda-developers.com/showthread.php?t=1792101 and http://rootzwiki.com/topic/25652-fixing-galaxy-tab-2-encryption/
I have discovered that by using aLogcat to track down the origin of the failure. The interesting part revealed to be: E/Cryptfs ( 87): Orig filesystem overlaps crypto footer region. Cannot encrypt in place.
To circumvent this problem, you will find in Cybermaus first post, two CWM update zip files that will do the trick in a simple and secure way. After flashing your ROM and wiping data with CWM, apply them, go to system encryption as described here:http://support.google.com/android/bin/answer.py?hl=en&answer=1663755, and after waiting one or two minutes (not more), the system should restart automagically to encrypt your /data partition.
Third step: making your phone even more secure and practical at the same time
-------------------------------------------------------------------------------------------------------------------
Android built-in encryption is in fact more or less Linux LUKS (http://en.wikipedia.org/wiki/Linux_Unified_Key_Setup). Plus, it is open-source so that everyone with the required skills can make an audit of the code to see if no security hole is present in the Android implementation. The underlying mechanism is strong and secure, as long as you use a strong password. I mean by strong, at least 12 characters that includes at the same time lower-case letters, upper-case letters, numbers and symbols. And it must be something impossible to guess for others while easy to remember for yourself. You will find a lot of resources on the internet on how to create such a password. For instance: https://help.ubuntu.com/community/StrongPasswords .
The problem with Android, in its attempt to keep the system not too complicated to use, is that the GUI (I insist: only the GUI, not the system) does not distinguish between the PIN or passphrase that you use to lock your phone when it is on, and the password used to encrypt the data that lay physically on your phone storage. So the casual user is in front of a paradigm: either he chooses a strong password for its data, but this will rapidly become tedious to type at least 12 characters to unlock his device several times a day; or he decides to use a PIN code, which is more practical to unlock the phone, and consequently uses a really weak password to encrypt its data which contains only digits, and thus may be cracked in a breath by any PC.
Fortunately, this paradigm is addressed and solved by small tools like EncPassChanger or Cryptfs Password (both requiring that your phone be rooted, which is by the way, paradoxically, a security hole if not used with caution ). See: http://nelenkov.blogspot.fr/2012/08/changing-androids-disk-encryption.html for complete notes about that. So for me, the only way, both secure and practical, to secure your phone is by using a PIN code of at least 4 numbers (6 is better). Then use a handy tool like EncPassChanger to have a true complex password for decryption at boot time.
Fourth step: increase security, without sacrifying practicability
-----------------------------------------------------------------------------------------
As I am paranoid, but at the same time don’t want my phone to become a source of annoyances, the previous “basic” steps were not enough for me.
So I decided to improve security in two ways:
1) By following the following tip, which I find great and is itself self-explaining: http://forum.xda-developers.com/showpost.php?p=26730989&postcount=2
2) By encrypting the photos I take with my phone, because these are linked with my private life and I won’t like that somebody gain access to them.
3) By encrypting documents I scan with CamScanner, for home and work, which may be sensitive.
4) By automating the action that disables USB debugging in case I forget to put it off after using it .
For point 2 and 3, documents lay on your sd card uncrypted. Android built-in encryption does not deal with both internal and external sdcard (just to be clear, by sdcards I mean partitions mounted as /mnt/scard or /mnt/scard2). To encrypt them you have to use once again an external tool. As I am an opensource fanatic for all that deal with security, I would recommend to use LUKS Manager (https://play.google.com/store/apps/details?id=com.nemesis2.luksmanager&feature=search_result and http://forum.xda-developers.com/showthread.php?t=1141467) which is based on dm-crypt module (yes, the same that Android uses for its build-in encryption), or Cryptonite (https://play.google.com/store/apps/details?id=csh.cryptonite&feature=search_result) which is completely open-source and implements the rock-solid Linux encfs on Android.
The latter is my personal choice. I do not use Crytonite in itself, except for creating the initial .encfs6.xml file. For everyday use, I use directly the Android port of the binary file encfs that comes with Cryptonite, and embed it into shell scripts. Up to now, no flaw, no problem. The password to open my encfs encrypted volumes is stored in a text file located on the /data partition. It is thus encrypted by Android and made accessible on boot when you decrypt this partition. So nothing more to remember.
To make things usable and practical, I use Tasker to automate the following things:
- Mount encfs volumes on start-up, by reading directly the password in the file located on /data
- Umount encfs volumes when usb is plugged
- Copy photos on a regular basis from the unencrypted /mnt/sdcard/DCIM to the safe place I created with encfs, delete AND wipe the original ones
Fifth step: be coherent about security
-----------------------------------------------------
Some people, torn apart by the paradigm described in Third step, by negligence or by lack of knowledge, strongly secure one part of the system, but make other parts big security holes.
Concretely, I am thinking about two examples: mixing encryption with pattern lock (or, even worse, with face unlock), or mixing encryption with usb debugging. Face recognition is just a jock. It is not reliable and fails very often. Moreover it is really easy to crack, with a photo for example. One of my colleague even achieved to unlock my phone with its own face, just because we are morphologically close enough. Pattern lock is not much better. (See: http://forum.xda-developers.com/showpost.php?p=37649447&postcount=6 and https://www.google.fr/search?q=smudge+attack).
So always ponder over (two times rather than one) each action you take that may touch system security.
Thanks lolo
I'm trying to use this on my VZW Galaxy S3 16Gb and this is what I'm seeing in TWRP v2.2.0:
Mounting System
Extracting system fixes
Update script starting...
Update script started
Disk /dev/block/mmcblk0p15: 13.1GB, 13140754432
4 heads, 10 sectors/track, 401024 cylinders
Units = cylinders of 64 * 512 = 32768 bytes
ERROR: unlikely size of KB
aborting operation!
Update script ended
Unmounting system...
Update Complete
Click to expand...
Click to collapse
edit: The same thing happens with both scripts.
I need to enable device encryption because my employer requires it for email and other Google Apps for Business apps. Thank you for your help!
Anyone know why full disk encryption isn't available on some (if not most roms)? Is it something that needs to be added with intent aside in the building process, or dependent on how the stock rom was set-up to work with?
I was hoping this would help get encryption working on an EVO ics rom which has encryption available, but when you click "encrypt phone" it just hangs on an android screen and doesn't actually do anything.
i was really happy to find your solution to enable encryption on my HTC desire S (ICS, rooted), but unfotunately it doesn't work. the same thing happen to me as it happened to mushu13, only different numbers in lines 5 and 6. same result whichever script i choose. please help, i really need system encryption.
thanky you very much!
First thing you should know, I am not an Android Guru. And unfortunately, if your phone is not an A789, I won't be able to help you deep in technical details. Cybermaus is the most skilled of the two of us, technically speaking, and he may lack time to answer correctly every request he is regurlarly faced with.
Okay, I do not know your phones and don't own them. So, distant debugging is much harder in these conditions. But the first things you should check, before applying Cybermaus' patches, are :
1) if encryption works with stock rom
2) follow thoroughly all steps I described in "Second step: offline protection" of the second post of this thread :
- your phone or tablet internal storage partitions must be seen by your system as block devices. This is the case with eMMC but not with Yaffs. If you don't have this information from the manufacturer, install Terminal Emulator from the Play Store and type 'mount' in it. You should see lines beginning with /[email protected] and /[email protected] If this is not the case, I fear encryption won't be able to work on your device.
- use aLogcat to track down the origin of the failure (see resources on the internet to learn how to use it, and links I have put in the second post)
3) Be sure that required modules are built into the kernel you use, especially dm-crypt
4) Post your results and cross your fingers that either this is a problem I have already encountered (in this case I may help you further), or Cybermaus see your posts.
While this script did allow me to encrypt my phone, it also shrunk my /data partition to roughly 1.1 GB.
Any ideas on how to expand it back to a reasonable size? I supposedly have 4 GB of ROM, and I assume more than 1 GB ought to be available for data.
Sent from my HTC Sensation using xda app-developers app
Thank you for your nice guide.
Only one thing is missing: baseband security.
Attacks on the baseband system requires very skilled people. Such as government agencies. It is believed they use baseband attacks to break into almost every mobile device. And there is only little you can do. Some vendors like Cryptophone have mobile devices with a hardened Android system. All others have no way to protect their device against baseband attacks.
Is this patch and reasoning still valid for newer android releases.
I am running a custom kitkat rom and twrp on a note 3 and can't encrypt so im looking for a fix.
I have been looking around for fixes but different posts blame different things.
Sometimes its the fact its a custom recovery, sometimes its that root is on the device and then there is this reasoning
Is there a way to find out the cause and fix for kitkat?
Virus
Hi, i tried to download your files
ICS_usrdata_fix-fs.zip
ICS_usrdata_shrink.zip
But the file are exe files with viruses.
Any ideas?
u2funker said:
Hi, i tried to download your files
ICS_usrdata_fix-fs.zip
ICS_usrdata_shrink.zip
But the file are exe files with viruses.
Any ideas?
Click to expand...
Click to collapse
Maybe false alarm.
Lossyx said:
Maybe false alarm.
Click to expand...
Click to collapse
no, but if you search for these file, you will find some which work and which are without viruses. Check the link..it is not an zip file..it is an exe file
@cybermaus: just tried flashing the two *.zips on my Galaxy S 4 Mini running CM 12 (Android Lollipop) because my logcat tells me I'm getting the described cryptfs error. It seems my /data partition doesn't have that 1 MB of unused space needed for encryption. Now I would love to encrypt my phone using CM's integrated function without having to completely format the internal storage (because that's the other workaround I found: flash stock rom, wipe data (factory reset), flash Custom Recovery, flash CM again)
Do you have the time and device to update your script so it works with Android Lollipop as well? I see a lot of people come across this issue recently so there would be definetly use for such a nice script like yours!
Thanks for sharing this with us!
-Teutone
no available for download any mirror ?
Or write the script on the thread.
Thanks
Can you post the scripts? links are dead!
---------- Post added at 16:33 ---------- Previous post was at 16:32 ----------
cybermaus said:
If you ever used CWM, CWMT or other non factory recoveries to wipe your data, you probably noticed that you lost the ability to encrypt your phone. Or maybe you did not even realize this is why encryption does not work.
For the Android phone encryption to work, it needs the /data (usrdata) partition to have a little bit of unused space between the end of the filesystem and the end of the partition. And as soon as you use CWM to wipe, it actually reformats using all space, and encryption does not work anymore.
User lolo250612 brought this to my attention, and together we created a update.zip that shrinks the /data filesystem by 1MB
In fact, we created 2 patches: One to shrink, and one to first repair the filesystem. The first will refuse to shrink if the file system is not clean and healthy. They will automatically find the correct usrdata partition device and its size. The shrink will then resize to 1MB less then the partition size (which means it could also be used to grow if you somehow had a filesystem a lot smaller, for example because you restored an smaller image from somewhere).
Both patches are created with statically linked e2fsprogs binaries and its own static copy of busybox shell interpreter. So they should work on all Android devices that use ext file system (probably all V2.3.1 Gingerbread and higher androids), and you should not lose any data because of this. But it is always good to make a backup.
We tested this on 2 phones, both ICS phones, and with both CWM and TWRP type recoveries, and are fairly certain it is safe to use. But to repeat, you should always take a backup of your phone.
Both patches can be found on my shared drive:
ICS_usrdata_fix-fs.zip
ICS_usrdata_shrink.zip
Procedure:
- Make backup of your phone
- Place files on SD card
- Boot into recovery
- Apply the shrink update
- If it tells you the filesystem is damaged apply the fix-fs update first
The patch only shrinks the filesystem, nothing is actually installed or removed on the phone. But if you use encryption, you could leave this patch on your SD card so that every time you wipe data, you can run the shrink patch again afterward to enable encryption again.
If you do use this, please report back in this thread, possibly mentioning your phone model and ROM you are using.
Click to expand...
Click to collapse
links are dead. Can you post the scripts?
I've looked this up a lot on the forum and I've come to a small conclusion (?)
UMS is "impossible" on all Nexus devices because both all the device data including Android itself exist on the same partition.
Why is it "impossible"? Why can't we just repartition the system?
Or even enable the mode but expose a virtual partition that's mounted on loopback as per this?
(couldn't post the link since I'm new. Google "inurl:how-can-i-use-my-galaxy-nexus-as-an-external-usb-storage-drive".. first result)
My Nexus 7 is rooted with CM10.1 installed. I couldn't find /sys/devices/platform/usb_mass_storage/ so I assume the kernel has no support for UMS.
Can anyone informed give me a brief overview on how I should move from this point? I assume recompiling a kernel? Any guides?
I'm new to Android but I'm an intermediate linux user. Please tell me if anything I'm saying is wrong or doesn't make sense.
And please don't try to convince me with MTP. I have my reasons.
★★★★[INFO]ANDROID ROM & How they Work★★★★
Parts of a ROM
i. The kernel.
Android (like many other Smartphone operating systems) runs on the Linux kernel. The Linux kernel was created in the early 1990’s by a gentleman named Linus Torvalds in Helsinki, Finland. It’s incredibly stable, incredibly friendly, and incredibly difficult for the layman to understand and modify. Thankfully it’s also very popular so it has been ported on to a multitude of hardware, including our Android devices.
Think of the kernel as an interface layer between the hardware and software on your device. The kernel decides when things happen, such as the LED indicator gets lit or when the soft button's LED gets lit. An application sends a request to the operating system to blink the LED. The operating system then sends the request to the kernel, which makes the light flash for the amount of time requested by the OS.
What sounds like a round-about way to get things done is also what makes the system so scalable and robust. Application developers only have to code in a way the operating system understands and the kernel makes it work on the hardware. This also keeps the application running in it’s own user-space and separate from the kernel. That means when you run the latest uber-cool app that wasn’t designed for your particular OS version, or is still very beta and it crashes, the kernel gives you the option to Force Close the application and the kernel can run untouched.
In a standard Android ROM (we will leave developer images and the like for another discussion) the kernel is bundled along with a set of instructions that tell the device how to load the kernel and the OS during boot. This is the boot.img that you see inside a zipped ROM that your not able to easily open. The device knows to extract this image to internal memory (the ramdisk) and follow a series of scripts (init scripts) to load the kernel and then the other portions of the OS. That’s what’s happening while you’re watching the boot animation. Interestingly enough this is done the same way for a PC, your smartphone, an Android tablet, or even a smart Linux powered toaster. If you’re feeling exceptionally geeky, plug your Android phone into the USB port on your PC and let the PC boot from the USB device. No, it doesn’t actually load, but you can watch the animation while it tries to match up the hardware support with what’s inside your PC. As I said, Linux is amazingly scalable and as a result so is Android.
What is a kernel? If you spend any time reading Android forums, blogs, how-to posts or online discussion you'll soon hear people talking about the kernel. A kernel isn't something unique to Android -- iOS and MacOS have one, Windows has one, BlackBerry's QNX has one, in fact all high level operating systems have one. The one we're interested in is Linux, as it's the one Android uses. Let's try to break down what it is and what it does.
Android devices use the Linux kernel, but it's not the exact same kernel other Linux-based operating systems use. There's a lot of Android specific code built in, and Google's Android kernel maintainers have their work cut out for them. OEMs have to contribute as well, because they need to develop hardware drivers for the parts they're using for the kernel version they're using. This is why it takes a while for independent Android developers and hackers to port new versions to older devices and get everything working. Drivers written to work with the Gingerbread kernel on a phone won't necessarily work with the Ice Cream Sandwich kernel. And that's important, because one of the kernel's main functions is to control the hardware. It's a whole lot of source code, with more options while building it than you can imagine, but in the end it's just the intermediary between the hardware and the software.
When software needs the hardware to do anything, it sends a request to the kernel. And when we say anything, we mean anything. From the brightness of the screen, to the volume level, to initiating a call through the radio, even what's drawn on the display is ultimately controlled by the kernel. For example -- when you tap the search button on your phone, you tell the software to open the search application. What happens is that you touched a certain point on the digitizer, which tells the software that you've touched the screen at those coordinates. The software knows that when that particular spot is touched, the search dialog is supposed to open. The kernel is what tells the digitizer to look (or listen, events are "listened" for) for touches, helps figure out where you touched, and tells the system you touched it. In turn, when the system receives a touch event at a specific point from the kernel (through the driver) it knows what to draw on your screen. Both the hardware and the software communicate both ways with the kernel, and that's how your phone knows when to do something. Input from one side is sent as output to the other, whether it's you playing Angry Birds, or connecting to your car's Bluetooth.
It sounds complicated, and it is. But it's also pretty standard computer logic -- there's an action of some sort generated for every event. Without the kernel to accept and send information, developers would have to write code for every single event for every single piece of hardware in your device. With the kernel, all they have to do is communicate with it through the Android system API's, and hardware developers only have to make the device hardware communicate with the kernel. The good thing is that you don't need to know exactly how or why the kernel does what it does, just understanding that it's the go-between from software to hardware gives you a pretty good grasp of what's happening under the glass. Sort of gives a whole new outlook towards those fellows who stay up all night to work on kernels for your phone, doesn't it?
Click to expand...
Click to collapse
ii. The operating system.
Once the kernel is loaded, the init scripts tell the Operating System to load. Android is the user interface for a custom built Java virtual machine called Dalvik. Dalvik was written by Dan Bornstein, who named it after the fishing village of Dalvik in Iceland, where his family originated from. The debate of which Java VM is superior is best left for another discussion, so I’ll simply say that DalvikVM is a register-based machine versus true JavaVMs which are stack based.
The Dalvik machine creates executable files (.dex files) which can be interpreted by the OS and run by the end user. These .dex files are OS version dependant. That simply means that applications and core functions built to work with one version of Android may or may not work well with other versions. Google provides the tools through it’s Software Development Kit (SDK) for applications to communicate with the OS.
Click to expand...
Click to collapse
iii. Core functions.
No smartphone would be complete without a set of functions that allow the device to be used as intended. Things like the phone and dialer interface, the calendar, the messaging system are core functions of the Operating System. In Android, these are run on top of the kernel as separate applications. The merits (or lack of) of providing these needed functions as separate applications is once again best left for another discussion, but this is what allows developers like HTC or Motorola to replace the standard functions with alternatives that provide a different look and feel from stock. HTC’s onscreen keyboard or Motorola’s MotoBlur contact list are great examples of this. The “little guy” isn’t left out of the mix either. Handcent SMS or Chomp SMS can integrate into the OS very well, as most of us already know.
An additional set of Core Functions are provided by Google. Popularly called GoogleBits, things like Gmail, sync, Gtalk and the Android Market are applications written by Google that give an extra set of useful functions to the OS. You’ll find these on all smartphones, as well as many other Android devices.
Click to expand...
Click to collapse
iv. Optional applications.
These are applications provided by the manufacturer to give the device even more usability. Things like the Amazon MP3 store, PDF readers, Corporate Calendar etc. allow you to do even more with your device. Remember - Droid Does
Click to expand...
Click to collapse
B. How is a ROM packaged?
In most cases a ROM will come packaged in a .zip file. The recovery image’s kernel (yes, it has one too!) has the ability to unzip and copy the contents into the correct place. Inside this zip file is a folder (META-INF\com\google\android\) that contains a script prepared by the ROM “cooker” (another of those techie terms - it means the person(s) who developed the ROM) that tells the system what to format, what to copy and where, and any file operations that need to be done. Each device does things a bit differently, but this script is where it all gets done. More on this folder later.
You’ll also see a /system folder. This is the meat of the ROM. It has the necessary OS files, the Core functions, and any optional applications the cooker decided to include. The folder is structured the same way it is on your device - /system/app, /system/framework, etc. The whole tree is usually copied over and the existing /system folder is overwritten. The cooker uses the script to tell the kernel to erase the existing system folder, copy the new folder over, and set the file permissions.
Sometimes you will also see a data folder. This usually is space set up for optional applications, including optional system tools like busybox or SuperUser white list. These applications could be placed in the /system folder, but placing them in the data folder makes it easier for the end user (you and I) to remove or update them as needed.
You’ll also notice a META-INF folder. This contains the update script we talked about earlier, as well as secure keys that need to be provided so the device knows the update can be trusted. A special note needs made here. Trusted means that the update is trusted to be in the correct form to load the device. It in no way means the ROM is safe from malicious code. Anyone is able to use a set of test keys and create a ROM that will flash and run your device - even those people with bad intentions. Flashing and running a custom 3rd party ROM is putting faith in the cooker that he or she not only knows what they are doing, but are honest as well. Also, some Motorola custom ROMs will have a small update.zip stored inside this folder to be run on first boot of the device.
Finally we are left with the boot.img file. This is the kernel and ramdisk image we discussed earlier. Your phone copies this over to be decompressed and run when the device boots.
Click to expand...
Click to collapse
2. How do I install a ROM?
In this section we’re discussing how to install a custom 3rd party ROM. ROMs from the manufacturer usually have a utility that runs on your PC to flash and load the new image.
A. Got Root???
Yes ?:good:!!!
Custom ROM’s simply will not load on devices that aren’t rooted. In theory, it may be possible to sign a 3rd party ROM with the keys that the stock recovery image will flash, but for the most part you need to have flashed a custom recovery image before you can change your device’s ROM. Instructions and tutorials on how to root your device are all over the internet. Some are good, some are bad. The hacking forum is a great place to go and learn more about rooting and how to successfully get it done on your device.
Click to expand...
Click to collapse
B. Recovery
Most Android devices have had a custom recovery image written for them. This will overwrite the stock recovery image, allowing you to flash 3rd party ROMs as well as giving extra functionality. Help with finding and flashing the custom recovery image for your device can also be found in the hacking forum. The installation of a custom recovery image also allows for a very important function. Backup and restore.
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Click to collapse
.C. Nandroid
Nandroid is a set of bash scripts and code written by that copies the state of your system and stores it in a folder on your SD card. You can then use the restore function of Nandroid to restore to this point at any time. This is a priceless feature and reason enough to root your phone. It’s included by default in most custom recovery images, and the code is freely available to use if you’re inclined to write your own recovery image.
Click to expand...
Click to collapse
In most situations, using Nandroid to back everything up is easy:
1. Verify you have a memory card with enough free space (~300MB to backup, ~500MB to restore).
2. Reboot your device into recovery. It’s slightly different for each device, once again hacking forum FTW!
3. Navigate through the menu and select the Nandroid Backup function.
4. Apply your choice and wait for the device to tell you it’s finished.
It’s always good practice to copy the entire nandroid folder from your SD card to a safe place. You can then copy it back to the SD card if the card is ever damaged, lost or erased.
D. Copy and Flash
You’re rooted, have downloaded a custom ROM, have your system backed up and are now ready to flash your device. This is not nearly as scary as it sounds.
1. Mount your SD card to your PC, and copy the .zip file to the root folder of the card. Don’t unzip the file, and don’t look for a folder called root. The root folder in this case means the base folder, what you will see when you mount your card to a PC or the device.
2. Reboot your phone into recovery.
3. Navigate through the recovery menu and select the flash update option. Depending on your recovery image, the file may need to be named update.zip, or you may be able to select any zip file on your card as long as it’s the correct format. The cooker knows this as well and if the ROM needs to be named update.zip it will be.
4. Apply your choice and wait for your device to tell you it’s finished.
5. Reboot.
Click to expand...
Click to collapse
It’s worth noting that many times a new ROM will require that you wipe and factory reset your devices data. While inconvenient, it’s often necessary to get rid of the old data as it may be incompatible. As long as you’re using the cloud for calendar and contacts, they will be re- downloaded and stored back on your device automatically.
Dirty flash and Clean flash
A dirty flash is only wiping cache and davlik then flashing your ROM....
a Clean flash is at LEAST factory reset/data wipe + wiping davlik(factory wipe takes care of /cache also)... Maybe doing a format /system also.
***Odin***
Odin is the ROM Flashing Tool for SAMSUNG smartphones. ROM files flashable with Odin come with .tar extension.
Most of the ROMs you are going to flash with Odin are the official stock Samsung ROMs (or leaked stock ROMs). Custom ROMs are rerely flashable by Odin because they come with .zip extension that Odin does not recognize (it recognizes .tar files).
Custom kernels, however, are sometimes provided in .tar format by their developers (e.g. CF-Root kernels), so that they can be flashed by Odin. When your phone is new and running official firmware you most often cannot flash a custom ROM to it because a Samsung phone often requires a custom recovery and root rights that are included in a custom kernel to be able to flash custom ROMs. That's why Odin often comes in handy in rooting and flashing a custom firmware to your phone because you (often) can flash a custom kernel with it that already includes root and custom recovery and enables you to flash custom firmware (custom ROMs). I use the word "often" very frequently in the previous sentence because every Samsung smartphone is different and requires various procedures for rooting it and flashing custom ROMs (see the section about using Odin below).
If it comes to stock ROMs, the best source of stock (official) Samsung ROM files is located at this excellent website: SamMobile.com/firmwares (link). It requires registration (it's free) and I encourage you to set up an account there because you will most likely use this site several times during your stay at XDA. You will most likely come across 1 .tar or 3 .tar file ROMs there, flashable by Odin. Refer to the Odin flashing guide below for more info.
Click to expand...
Click to collapse
****Heimdall****
What is Heimdall?
Heimdall is a cross-platform open-source tool suite used to flash ROMs onto Samsung Galaxy S devices.
How does it work?
Heimdall uses the same protocol as Odin to interact with a device in download mode. USB communication in Heimdall is handled by the popular open-source USB library, libusb-1.0.
Why “Heimdall”?
The flashing software Odin is named after the king of gods in Norse mythology. Loke, the software component on the Galaxy S that provides functionality to flash, may also to be named after an important character in Norse mythology, often translated as Loki. As such I have named my flashing software Heimdall, after the Norse god, and guardian of the Bifrost Bridge.
What platforms does Heimdall run on?
Linux, OS X and Windows (XP, Vista, 7 etc.)
Why use Heimdall when we can use Odin?
Odin is generally unreliable and only runs on Windows systems. Furthermore, Odin is leaked Samsung software that is not freely available or well understood by the community.
Is Heimdall safe?
No matter what method you chose, flashing firmware onto your phone has a lot of potential for disaster. We have tested Heimdall with a variety of phones flashing several different firmware versions resulting in a 100% success rate. As such we believe that Heimdall is generally reliable. However keep in mind, just like any flashing software, Heimdall has the potential to brick your phone if not used correctly.
How do Galaxy S phones get bricked when flashing?
Besides the inherent risks like power outs, accidental removal of the USB cable etc. The Galaxy S appears to be running extremely unreliable USB control software.
A failure to flash does not automatically equate to a bricked phone. However if you're extremely unlucky and the flash fails whilst transferring the primary boot-loader, secondary boot-loader or params.lfs (all quite small) than you've got yourself a paper weight that you're hoping Samsung will replace.
Please be extremely careful mixing files from different firmware releases. Don't do so unless you're certain it will work!
What Galaxy S variants has Heimdall been tested with?
We’ve tested Heimdall with a Galaxy S GT-I9000 (8 GB) from the United Kingdom and Galaxy S GT-I9000 (16 GB) from Australia. We don’t personally have access to any other devices to test with, however users have confirmed Heimdall functions correctly with the AT&T Captivate, Bell Vibrant, Telstra GT-I9000T, Epic 4G and the Galaxy Tab.
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Click to collapse
^
CWM Errors and Solutions
ERRORS encountered in CWM Recovery
.
What is CWM Recovery ?
ClockworkMod Recovery is a custom recovery for many Android devices. It is considered to be the most popular recovery for Android due to its easily-ported nature, and integration with ClockworkMod ROM Manager by Koush(Koushik Dutta). The easiest way to recognize it is by the printed name when it first starts, and the background logo of a gear and hat.
Click to expand...
Click to collapse
ERROR STATUS 6
This is usually caused by CR/LF EOL(Windows style End Of Line) in updater-script. Change it to LF EOL(Unix Style EOL) using Linux command: dos2unix updater-script, then re-signing the ZIP, will usually fix this error.
Click to expand...
Click to collapse
ERROR STATUS 7
This is usually caused by a corrupt download, or bad file signature. Re-downloading (or re-signing) the ZIP will usually fix this.
Click to expand...
Click to collapse
We have been consistently seen and heard people facing error “Status 7″ error while trying to flash or install
custom ROMs or firmware packages on their Android smart phones or tablets with ClockworkMod Recovery. Many
of the users are nowadays facing this problem with CWM Recovery while flashing .zip files of modded or custom
Ice Cream Sandwich (ICS) or Jelly Bean (JB) ROMs on their devices. So, you have also downloaded a custom ROM,
placed its .zip file in your phone’s or tablet’s SD card, booted into ClockworkMod Recovery, selected – “install zip
from sdcard” and then chosen the .zip file of the ROM to get it installed on your device. But instead of getting
flashed successfully, if you are facing the issue mentioned below, then just keep reading this article to find out
what’s wrong and fix up the problem :
Finding update package…
Opening update package…
Installing update…
Error in /sdcard/custom-jelly-bean-rom.zip (Status 7)
Installation aborted
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Click to collapse
or the following error right after CWM recovery shows –
Installing update…
assert failed: getprop(“ro.product.device”) == “I9103″ || getprop(“ro.build.product”) == “I9103″ || getprop
(“ro.product.board”) == “I9103″
Error in /sdcard/android-4-1-1-ics-rom-latest.zip (status 7)
Click to expand...
Click to collapse
So, if you are facing any of these errors while trying to install the desired custom ROM package on your Android
phone or tab, then you may try a various things or steps which may turn out to be the workaround of this
problem. Here are a few tips to get this “Status 7” error fixed in ClockworkMod Recovery and flash the ROM
successfully on your device :
(1) First of all, make sure your device’s bootloader is unlocked. If it is already unlocked but you are still
not able to flash the ROM, then just extract the .zip file of the ROM into a new folder, find the boot.img file from
that directory and flash it up on your phone or tablet via fastboot on your PC.
(2) Make sure that you are having the appropriate Radio or Baseband version installed on your device which is
supported by the custom ROM you are trying to flash. Most of the ROMs requires the latest version of Baseband, so
just update or upgrade your device to the latest Baseband version and then try to install the ROM once again.
(3) Update your device to the supported / latest build of official firmware before trying to install the ROM. You can
do it from – Settings > About Phone / Device > Software Update.
(4) Make sure you are having the supported or required kernel installed on your phone or tab. If it’s not, then flash
a new kernel right away and try to install your custom ROM once again.
(5) Is the ROM which you are trying to flash really works ? Find out whether it is working for other users or not.
Click to expand...
Click to collapse
Error Status 0
Well sometimes while flashing some ROMs especially the cooked ones we get Error status 0 in the CWM Recovery
this error is an indicator of Wrong Update Binary.This is usually caused by an incompatible update-binary in edify ZIPs. Replacing it with a compatible one, then re-signing the ZIP, will usually fix this error.
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Click to collapse
Partitions
Now it's time for the partitions :good:
Let’s start with a list of standard internal memory partitions on Android phones and tablets. These are:
/boot
/system
/recovery
/data
/cache
/misc
In addition, there are the SD card partitions.
/sdcard
/sd-ext
Note that only /sdcard is found in all Android devices and the rest are present only in select devices. Let’s now take a look at the purpose and contents of each of these partitions.
/boot
This is the partition that enables the phone to boot, as the name suggests. It includes the kernel and the ramdisk. Without this partition, the device will simply not be able to boot. Wiping this partition from recovery should only be done if absolutely required and once done, the device must NOT be rebooted before installing a new one, which can be done by installing a ROM that includes a /boot partition.
/system
This partition basically contains the entire operating system, other than the kernel and the ramdisk. This includes the Android user interface as well as all the system applications that come pre-installed on the device. Wiping this partition will remove Android from the device without rendering it unbootable, and you will still be able to put the phone into recovery or bootloader mode to install a new ROM.
/recovery
The recovery partition can be considered as an alternative boot partition that lets you boot the device into a recovery console for performing advanced recovery and maintenance operations on it. To learn more about this partition and its contents, see the ‘About Android Recovery’ section of our guide to ClockworkMod recovery.
/data
Also called userdata, the data partition contains the user’s data – this is where your contacts, messages, settings and apps that you have installed go. Wiping this partition essentially performs a factory reset on your device, restoring it to the way it was when you first booted it, or the way it was after the last official or custom ROM installation. When you perform a wipe data/factory reset from recovery, it is this partition that you are wiping.
/cache
This is the partition where Android stores frequently accessed data and app components. Wiping the cache doesn’t effect your personal data but simply gets rid of the existing data there, which gets automatically rebuilt as you continue using the device.
/misc
This partition contains miscellaneous system settings in form of on/off switches. These settings may include CID (Carrier or Region ID), USB configuration and certain hardware settings etc. This is an important partition and if it is corrupt or missing, several of the device’s features will will not function normally.
/sdcard
This is not a partition on the internal memory of the device but rather the SD card. In terms of usage, this is your storage space to use as you see fit, to store your media, documents, ROMs etc. on it. Wiping it is perfectly safe as long as you backup all the data you require from it, to your computer first. Though several user-installed apps save their data and settings on the SD card and wiping this partition will make you lose all that data.
On devices with both an internal and an external SD card – devices like the Samsung Galaxy S and several tablets – the /sdcard partition is always used to refer to the internal SD card. For the external SD card – if present – an alternative partition is used, which differs from device to device. In case of Samsung Galaxy S series devices, it is /sdcard/sd while in many other devices, it is /sdcard2. Unlike /sdcard, no system or app data whatsoever is stored automatically on this external SD card and everything present on it has been added there by the user. You can safely wipe it after backing up any data from it that you need to save.
/sd-ext
This is not a standard Android partition, but has become popular in the custom ROM scene. It is basically an additional partition on your SD card that acts as the /data partition when used with certain ROMs that have special features called APP2SD+ or data2ext enabled. It is especially useful on devices with little internal memory allotted to the /data partition. Thus, users who want to install more programs than the internal memory allows can make this partition and use it with a custom ROM that supports this feature, to get additional storage for installing their apps. Wiping this partition is essentially the same as wiping the /data partition – you lose your contacts, SMS, market apps and settings.
With this, we conclude our tour of Android partitions. Now whenever you install a ROM or mod that requires you to wipe certain partitions before the installation, you should be in a better position to know what you’re losing and what not and thus, you’ll know what to backup and what not.
You should at least post the source of such a large copy paste post.
Sent from my GT-N7100 using Tapatalk 2
Source? How do you post a source for an article which is compiled from 10+ sites? Plus my own addition?
Started from the bottom
Good job man, this saves me the time to do all this researches.
Keep it up
Best regards
Sifou
Using a Samsung N7100
sos_sifou said:
Good job man, this saves me the time to do all this researches.
Keep it up
Best regards
Sifou
Using a Samsung N7100
Click to expand...
Click to collapse
DO tell me if you have some suggestions for the thread.
"Thanks button is just to avoid "THANKS" posts in threads. Nothing more than that. Don't ask in signature or post for it and defeat the purpose why it was introduced"
I think that this is a pretty good summary of the basics. I even converted it to epub and stocked it on my e-reader for reference
You can get to the details if you want? Adding some info about flashing softwares like odin and the Linux based one (i don't remember it name)
The different recoveries available and their advantages vs désavantages
How to protect yourself from malicious applications, starting from knowing what are permissions...
Keep it up mate
Best regards
Sifou
Using a Samsung N7100
sos_sifou said:
I think that this is a pretty good summary of the basics. I even converted it to epub and stocked it on my e-reader for reference
You can get to the details if you want? Adding some info about flashing softwares like odin and the Linux based one (i don't remember it name)
The different recoveries available and their advantages vs désavantages
How to protect yourself from malicious applications, starting from knowing what are permissions...
Keep it up mate
Best regards
Sifou
Using a Samsung N7100
Click to expand...
Click to collapse
Heimdall?
"Thanks button is just to avoid "THANKS" posts in threads. Nothing more than that. Don't ask in signature or post for it and defeat the purpose why it was introduced"
Tha TechnoCrat said:
Source? How do you post a source for an article which is compiled from 10+ sites? Plus my own addition?
Started from the bottom
Click to expand...
Click to collapse
I guess you have a point, it's just the scientist in me with source-referral-ocd.
Sent from my GT-N7100 using Tapatalk 2
adytum said:
I guess you have a point, it's just the scientist in me with source-referral-ocd.
Sent from my GT-N7100 using Tapatalk 2
Click to expand...
Click to collapse
DO tell me if you have any problems or if you want something to be added.
"Thanks button is just to avoid "THANKS" posts in threads. Nothing more than that. Don't ask in signature or post for it and defeat the purpose why it was introduced"
Thread updated with Odin and Heimdall information.
"Thanks button is just to avoid "THANKS" posts in threads. Nothing more than that. Don't ask in signature or post for it and defeat the purpose why it was introduced"
Tha TechnoCrat said:
Source? How do you post a source for an article which is compiled from 10+ sites? Plus my own addition?
Started from the bottom
Click to expand...
Click to collapse
By listing ALL the different sources? And obviously crediting yourself with bits you've added.
Sent from my GT-N7100 using xda premium
You should make the title of the thread more presentable though.
Simone said:
You should make the title of the thread more presentable though.
Click to expand...
Click to collapse
Would like some suggestions.
"Thanks button is just to avoid "THANKS" posts in threads. Nothing more than that. Don't ask in signature or post for it and defeat the purpose why it was introduced"
Tha TechnoCrat said:
Would like some suggestions.
"Thanks button is just to avoid "THANKS" posts in threads. Nothing more than that. Don't ask in signature or post for it and defeat the purpose why it was introduced"
Click to expand...
Click to collapse
You should think of your own. That would be the best
Make it more professional looking, though.
Everything else is good.
Guys I have got my Note 2 finally. Will compile some guides for it too.
Sent from my GT-N7100 using xda app-developers app
You bought a note 2? Congrats mate !
Best regards
Sifou
Using a Samsung N7100
sos_sifou said:
You bought a note 2? Congrats mate !
Best regards
Sifou
Using a Samsung N7100
Click to expand...
Click to collapse
Thanks buddy. Get ready for more guides
Sent from my GT-N7100 using xda app-developers app
Hello all,
I know there are many people who are curious about android or/and are about their new device. With this in mind, I have decided to give a brief idea about Android and its different aspects. I will use as simple words as possible.
Every highlighted word is a term that is used often at XDA or just refers to the word in FAQs in case you cannot find it.
ANDROID is an open-source (thus possibilities endless) mobile operating system (OS) based on the Linux kernel and currently developed by Google
With a user interface based on direct manipulation, Android is designed primarily for touch screen mobile devices such as smartphones and tablet computers, with specialized user interfaces for televisions (Android TV), cars (Android Auto), and wrist watches (Android Wear).
ANDROID is usually based on these four major components:
ROM :
It is the system on which phone works (like windows for PC). Or simply called an Operating System. Can be Custom/Stock. Usually you need a custom or official tool to install/ repair a STOCK rom.
KERNEL is a part of ROM which is a programmed code that tells the phone how to function in accordance to the ROM & hardware capabilities. It can also be Custom/Stock. Sometimes they are used to enhance user experience, performance, battery life by small changes made to them. Some kernels are specific to ROMS.
DIFFERENCE BETWEEN CUSTOM/STOCK
When you buy your phone/tablet from a retailer, you are on STOCK ROM and STOCK KERNEL. (its from your mobile manufacturer and in this case straight from Google as it is a nexus device. Thus it is called a STOCK ROM/ STOCK KERNEL.
The STOCK ROM & KERNEL is usually an all-rounder to fit most of the users. However, some people are not happy with the limited option available on their devices. As Android is open sourced, and thus easily customized, they want to explore different options by tweaking their devices
In other words, some people like gaming on their devices while other want to increase the battery time, speed, performance etc and the possibilities are very vast as what we want from our devices. Like a person who likes to read books on his device would not care for heavy gaming performance but appreciate if he can get more juice out of his device so he can read more on a single charge.
Therefore, we can say we all need different flavours and thus there is a need for customisation. However, there could be some minor disadvantages too that come with some advantages like overclocking can result in heating and quick battery drain while it increases performance. Also, increased battery life might slow down your device if you are tweaking or under-clocking it too much Therefore, most of the developers try to find the best combination of both performance and battery. However, some custom ROMS/Kernels are developed with specific functions in their core like they might focus only on performance and gaming while other might just ignore heavy gaming and focuses on battery usage. Therefore, it is to your advantage to use your device how you like want it to function according to your preference.
By customisation, we run our devices to our needs and get the most out of it in accordance to how we want to customise it.
SOME CONSIDERATIONS
All devices ROMs and KERNEL are specific. This means stock/custom ROM for every device is specific so you cannot flash a ROM which is made for other device. This can permanently damage your phone. A famous Custom Rom is CyanogenMod which is currently on version 12.1. Although the ROM would be same for many devices, but you can not flash CM12.1 for Xperia M to Xperia M2 etc. In the same way, you can not flash custom/stock kernel of one device to another.
Rom can be installed via official tools provided by manufacturer or by using custom tools. Usually when you flash a STOCK ROM, it flashes SYSTEM+KERNEL+RECOVERY. However, some unofficial tools can help you flash any one component of the ROM. It could be Kernel/ Recovery or System.
RECOVERY
Recovery is also a part of ROM which is basically a backup mechanism of your device which lets you install stock ROM to your device if something has been corrupted in your device software. However, many CUSTOM recoveries are available which are necessary for flashing CUSTOM ROMS, MODS to modify your ROM and also you can backup your ROM(called nandroid backup), partition your sd card amongst many other uses. Recoveries could also be flashed via kernel as they are preinstalled.
BOOTLOADER is basically a lock in your device which doesn't allow modifications to your phone by the Manufacturer. Unlocking bootloader voids your warranty and stops automatic updates of your STOCK ROM. However, you can easily lock your bootloader again any time or manually install STOCK Updates.
Remember you should usually unlock bootloader before rooting unless you are installing a custom rom which is pre-rooted and allows locked bootloader.
ROOTING
This is basically a powerful exploit to take over your system and kernel of your device. It simply means that some system files which couldn't be modified can be changed now. It is as if you have complete power of your ROM and hardware. There are no restrictions from your manufacturer and thus you can change values , overclock your processor or put your hardware in hibernation to increase battery life, turn on/off your cores , speed or enforce 3D gaming cards to play HD games which you couldnot play before. However, this is a very tricky business so if you mess it up and not sure what you are doing, you can really end up with a bricked phone.
Usually apps are used to change these values or it could be done via SDK tools/ programming. To be sure if you are rooted or not, you can install ROOTCHECKER app from PLAYSTORE.
ADVANTAGES OF ROOTING
- You get full access to your phone's Hardware and software
- You can Overclock CPU clock speed and make phone faster
- You can Install many mods to improve camera, audio and video playback quality
- You can Install Beats Audio Drivers/others to enhance audio output
- You can increase speaker / earphone volume using volume hack
- You can Install Custom ROMs and Apps
- You can take the hell out of your device and Improve user experience
Rooting is safe and reversible, You can unroot your phone if you want. It won't void you're warranty etc
DISADVANTAGES OF ROOTING
-Chance to brick your device if the wrong software gets flashed. This can be EASILY reversible
-Warranty is void. You can flash STOCK ROM again and no one will have a clue you did that. So it can be reversible.
-Because, after Rooting you give permission (apps prompt, it's not by default) to apps to change values so if you give it to a malicious app, it can result in Viruses or security/privacy breach.
In all honestly, I am using rooted devices for over 5 years now and I never had any problem with viruses however, I have bricked my device innumerous times by accident. (I have flashed and rooted my device almost every one to two weeks and I have bricked my devices so many times in testing phase of Roms). I was always able to retrieve back the device with some tools and thus it was not much of a problem.
DIFFERENCE BETWEEN GOOGLE NEXUS DEVICE AND A NON NEXUS DEVICE
GOOGLE NEXUS DEVICES give you vast freedom to install custom roms and it is comparatively very easy to unlock bootloader of these devices so a custom Rom can be flashed. (Flashing rom is equivalent to installing windows in PC). You can understand that a Nexus device only needs one command to unlock its bootloader while others could trouble you a lot for that.
Also, Google is very quick with updates on their devices which mean that you will get the latest software updates officially as they come out. Thus, even staying on STOCK ROM is not a bad choice for many users. Every update increases stability and gets rids of bugs. And of course, sometimes the bugs are not ironed out well and come back
NON NEXUS DEVICES do not give you as much freedom as a Nexus device. It is usually much harder to unlock their bootloader, develop on these devices and usually some exploits are needed to run custom ROM/root/kernels. Manufacturers or these devices try their level best
to narrow down the exploits as in other words, the more exploits a device has, the less secure it tends to be.
SOME CUSTOMISATION DIFFERENCES
As it is a nexus device so Asus has no say on any customisation at all. Thus, Nexus devices are said to run the PURE ANDROID and give you the best android experience in my opinion. However, usually manufacturers customise pure android from Google. To understand better, Google is responsible for development of the android OS so every new version is made by Google and then it is open sourced to manufacturer of different devices. Manufacturers like Samsung/Sony/Motorola/HTC customize the code provided by Google to customize it to their likings. This can result in some added options but can also result in slow performance if there has been too much customization from a device maker. Google itself is only responsible for the software and DOES NOT make any hardware itself.
Also, many manufacturers take a small fee from some app developers and install their apps with every device they produce. It is good news for app developer and manufacturer but usually a burden for users as not only they hog RAM, diskspace, and slow down the device they also are useless to many users. Referred to as BLOATWARE
SUPPOSE YOU HAVE DECIDED TO INSTALL CUSTOM ROM/ KERNEL.
This is a short synopsis of steps which are explained in details later in the post :
1.Unlock your bootloader
Some phones have unlocked bootloaders out of box (Not anymore)
2.Root your phone , which can be done via flashing a custom prerooted kernel or by binary method. There are innumerous ways now actually so usually visiting your device forum will help you find it.
3. Flash a recovery. This step can be done before or after unlocking your bootloader. Even you can root your phone via flashing SuperUser in recovery. However, sometimes, you need a rooted device before you can install a custom recovery using exploit/ scripts method.
SOME COMMON MISTAKES AND PREREQUISITES:
1. Make sure what ever you do, do it as administrator on your PC.
2. Make sure drivers are installed properly for your device.
3. Make sure, USB debugging is ON
4. Unknown Sources is ticked as well
5. Windows 7 is usually quick to install drivers itself. In windows 8 however you have to manually install drivers.
6. There are tools like SDK which is about 500mb which can help you to install drivers/fastboot etc but this is the long route. I suggest you just find platformtools in attachment which would be enough for cmd commands.
UNLOCKING BOOTLOADER :
I will give you a rough idea and it is NOT a guide to unlock your bootloader !
Basically, when you buy your phone it is locked from the manufacturer so no changes can be made to the software(STOCK ROM & KERNEL ) and thus this way, they can stop users to modify their software which might damage the device and they do not want to be responsible for that. So unlocking bootloader voids your warranty. However, this can be reversible.
ROOTING :
What you do in rooting is either flash a kernel via fastboot or exploit your device using binary method. This gives you permenant root, however there are ways to get temporary root too.
ROMS & KERNELS :
You choose a rom to your likings and then flash it via recovery. Usually the instructions are given on every rom as there is slight change as to how to flash it.
There many Roms & Kernels made by developers after lots of hardwork and testing. Thus every rom that surfaces might not be good for you but best for another user. Thus, it is never good to compare roms. What might work for you might not work for another.
I hope this helps!
MORE TERMS CLICK HERE
DEVELOPMENT PROCESS
INTRODUCTION
I am starting this forum in hope of educating my readers about ROM development according to my experiences. Further, I will highlight what is the usual developers' thought process before they decide to build a ROM for a specific device. The reasons why they usually choose a certain device or why they prefer one device over another would also be stated briefly. I also have intention of looking into ways how we can speed up ROM productions for any device and what you can do to play your part.
I UNDERSTAND YOUR FRUSTRATION FOR NO CUSTOM ROMS EVEN AFTER SOME MONTHS BUT THIS DOESNOT GIVE YOU THE RIGHT TO SPAM
I am sure many of you must be really disappointed by the lack of development for your device and I know this must be frustrating when we see other devices are getting ROMS so quickly. I know many are too excited when they find a little about any OTA/ Custom ROM and sharing such news is fully justified. However, it's beyond my logic & thinking why the forums are SPAMMED for any little information they might find anywhere regardless of their sources or if it has been ALREADY POSTED. I reckon many of these threads could have been avoided by simply searching in the forum.
ROM DEVELOPMENT
I can assure you that many develoeprs are working very hard to PORT and develop different ROMS for a device. However, the reason we can not see any CUSTOM roms till yet is due to complicated nature of a device itself.
Usually developers prefer a device which is :
1. Easy to work with, less complicated to code with or in other terms DEVELOPER friendly. For example, for a while I had a real issue with HTC phones as they have too many things to work with like Bootloader, S Lock, Radios, Hboot version etc while in Nexus devices you only need to unlock your device with one fastboot command. That's all and you are ready to flash ROMs.
2. Personal preference of Device. This simply means that we all have different tastes and thus we choose different devices. A certain developer might only work for a certain brand while other might work with few brands. This has nothing to do with anything but a personal choice.
3. A device that promises reward in terms of money/self satisfaction. Developers usually go for devices which have most active users so if their intention is also to get some money out of it in terms of donation, this will work well with devices which are more in number.
4. Knowledge about a certain brand more than another.
5. MONEY TO BUY A CERTAIN DEVICE/DEVICES. Suppose a developer wants to make ROMS for Xperia L/ SP/Z and Xperia U. Yet he only has 500 dollars to choose from. He then will have to make a choice between devices and this will eventually mean that not all of the devices get the same treatment. Money is the most decisive factor why a developer doesnot chose your device but rather another. For example purpose only, if I have to choose between devices, I might prefer SP over Xperia L as I can see more future of SP than Xperia L(I might be wrong).
6. Simply he bought a device or it is gifted/donated to him
SOME REQUESTS
Please STOP bugging developers by trivial questions. Just think how many other people ask the same question and it gets very frustrating to actually work on the device itself.
Every developer has a LIFE apart from developing ROMs. They also have a family, school, work, hobbies, bad days and so much like us. So they will do it when they feel like doing it. Just sit back and relax. Enjoy your device until developer releases the ROM for your device. Asking a REASONABLE question seems plausible but asking same questions/useless questions without using brains is just STUPID. Kindly refrain from that.
If you have seen a developer who has taken the initiative to work on your device , the best thing to do is to be patient. Let him concentrate. Spamming and spamming again won't help really.Yet some users start SPAMMING developers, their twitters, blogs and accounts. That's really sad. You can discuss on the forum what you think about it but IRKING developers isnot really cool.
WHAT CAN YOU DO TO HELP DEVELOPERS AND SEE CUSTOM ROMS.
1. Search the form first and look for answers. DON'T start new posts/questions/threads when it is ALREADY mentioned in some other section.
2. STOP PMing/SPAMING developers but rather ask a question WHICH havenot been asked before in the forum. Do not engage in the habit of making a new forum for everything. Try to keep threads as little as possible.
3. Follow developers and see what they have updated about on their official twitter,facebook,etc rather than bugging them on different forums/social websites.
4 DONATE THEM. DONATE THEM . DONATE THEM!
The amount of efforts they put, sitting for hours in front of their PCs and I know how frustrating it gets when you try to run commands and everything seems to work yet you can not boot up your ROM. And worse, you can not find WHY really. Just a change in line in build.prop results in failure of ROM to boot up and specially working from source to build ROM is really really tough. The best thing you can do is being supportive and patient !
A ROM development requires not just EXCESSIVE amount of hardwork, time, energy and dedication but also they need MONEY to actually buy devices and try it on. They are happy and encouraged to keep on developing ROMs when they see their efforts are not wasted and they are rewarded and respected for what they do.
SOME BASICS OF ROM DEVELOPMENT
Usually this is required to make a full custom ROM
Blobs which contain hardware information which comes from hardware manufacturer like Qualcomm in case of Snapdragon processors
A fully functional device tree
Latest Android source (Or the android version source you want to build for)
Specific Custom ROM coding which is based on Android Source
Usually a device tree and kernel tree is needed before custom roms can be made available. This is a long trial and error process in which every component of hardware is made functional as usually manufacturers do not provide any code for their devices and thus new code is to be written which is very frustrating and long process!
FAQs :
BRICKED : Two types. hard or soft.
Hard bricked is when your phone hardware information is damaged. Now it is an expensive paper weight and it would only revive if you either send it to a JTAG technician or change motherboard of your device.
Soft is when your device ROM/kernel is damaged and thus it can be easily revived.
NOOB FRIENDLY : A guide that anyone with no knowledge of android can use
TWEAKINGimprove performance by making fine adjustments to it.
BLOATWARE Useless apps which come preinstalled in a stock rom from a manufacturer.
Sometimes, developers PORTone particular feature of a phone to another. This means, a function specific to one phone can be used in another but bear in mind, the hardware should support it. Like LG has knox feature which means that you can tap on the screen to wake it up or turn off the screen. Now it is a common feature of many kernels. LG was first to introduce it officially in their stock rom but the feature is a bit old. Even Asus Zenfone 2 uses tap to wake feature.
Nice One Brother
ARGHA_DAS said:
Nice One Brother
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I am glad this was of help to you
What's in the 'boot' partition?
Sent from my Nexus 7 using Tapatalk
AbyssBreak said:
What's in the 'boot' partition?
Sent from my Nexus 7 using Tapatalk
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This guide should be of help
/boot
This is the partition that enables the phone to boot, as the name suggests. It includes the kernel and the ramdisk. Without this partition, the device will simply not be able to boot. Wiping this partition from recovery should only be done if absolutely required and once done, the device must NOT be rebooted before installing a new one, which can be done by installing a ROM that includes a /boot partition.
/system
This partition basically contains the entire operating system, other than the kernel and the ramdisk. This includes the Android user interface as well as all the system applications that come pre-installed on the device. Wiping this partition will remove Android from the device without rendering it unbootable, and you will still be able to put the phone into recovery or bootloader mode to install a new ROM.
/recovery
The recovery partition can be considered as an alternative boot partition that lets you boot the device into a recovery console for performing advanced recovery and maintenance operations on it. To learn more about this partition and its contents, see the ‘About Android Recovery’ section of our guide to ClockworkMod recovery.
/data
Also called userdata, the data partition contains the user’s data – this is where your contacts, messages, settings and apps that you have installed go. Wiping this partition essentially performs a factory reset on your device, restoring it to the way it was when you first booted it, or the way it was after the last official or custom ROM installation. When you perform a wipe data/factory reset from recovery, it is this partition that you are wiping.
/cache
This is the partition where Android stores frequently accessed data and app components. Wiping the cache doesn’t effect your personal data but simply gets rid of the existing data there, which gets automatically rebuilt as you continue using the device.
/misc
This partition contains miscellaneous system settings in form of on/off switches. These settings may include CID (Carrier or Region ID), USB configuration and certain hardware settings etc. This is an important partition and if it is corrupt or missing, several of the device’s features will will not function normally.
/sdcard
This is not a partition on the internal memory of the device but rather the SD card. In terms of usage, this is your storage space to use as you see fit, to store your media, documents, ROMs etc. on it. Wiping it is perfectly safe as long as you backup all the data you require from it, to your computer first. Though several user-installed apps save their data and settings on the SD card and wiping this partition will make you lose all that data.
On devices with both an internal and an external SD card – devices like the Samsung Galaxy S and several tablets – the /sdcard partition is always used to refer to the internal SD card. For the external SD card – if present – an alternative partition is used, which differs from device to device. In case of Samsung Galaxy S series devices, it is /sdcard/sd while in many other devices, it is /sdcard2. Unlike /sdcard, no system or app data whatsoever is stored automatically on this external SD card and everything present on it has been added there by the user. You can safely wipe it after backing up any data from it that you need to save.
/sd-ext
This is not a standard Android partition, but has become popular in the custom ROM scene. It is basically an additional partition on your SD card that acts as the /data partition when used with certain ROMs that have special features called APP2SD+ or data2ext enabled. It is especially useful on devices with little internal memory allotted to the /data partition. Thus, users who want to install more programs than the internal memory allows can make this partition and use it with a custom ROM that supports this feature, to get additional storage for installing their apps. Wiping this partition is essentially the same as wiping the /data partition – you lose your contacts, SMS, market apps and settings.
With this, we conclude our tour of Android partitions. Now whenever you install a ROM or mod that requires you to wipe certain partitions before the installation, you should be in a better position to know what you’re losing and what not and thus, you’ll know what to backup and what not.
All credits to the writer Haroon Q Raja
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