Android 3+ has a nice feature -- device encryption. You can encrypt the contents of your device with a password, and after that this password must be entered during device boot, otherwise the data is permanently lost.
The bad thing is that this password is set to the screen lock PIN / password. So you either set a short password or PIN, that you can enter quickly each time you unlock your phone from sleep (but this provides weak encryption), or set a long password and have to type it 20-30 times during the day.
This stupid behavior may be fixed easily. Android provides command-line tool called 'vdc', an interface to Android Volume Manager. As written in "Notes on the implementation of encryption in Android 3.0" [1], it has a command 'cryptfs changepw', that allows changing encryption password. Of course this command must be executed as root.
vdc has some other commands related to encryption, one of them is 'cryptfs verifypw', that allows to validate the supplied password.
I'm currently writing an application that will assist user with changing encryption password. This is my first public application for Android. You can find a source code on GitHub [2]. It is very simple, but maybe android gurus here may find what to make better.
Comments and pull requests are welcome
Thanks!
[1] http source.android.com/tech/encryption/android_crypto_implementation.html
[2] https github.com/kibab/encpasschanger
Updated 30.06.2012: Added APK file!
Kibab said:
Android 3+ has a nice feature -- device encryption. You can encrypt the contents of your device with a password, and after that this password must be entered during device boot, otherwise the data is permanently lost.
The bad thing is that this password is set to the screen lock PIN / password. So you either set a short password or PIN, that you can enter quickly each time you unlock your phone from sleep (but this provides weak encryption), or set a long password and have to type it 20-30 times during the day.
This stupid behavior may be fixed easily. Android provides command-line tool called 'vdc', an interface to Android Volume Manager. As written in "Notes on the implementation of encryption in Android 3.0" [1], it has a command 'cryptfs changepw', that allows changing encryption password. Of course this command must be executed as root.
vdc has some other commands related to encryption, one of them is 'cryptfs verifypw', that allows to validate the supplied password.
I'm currently writing an application that will assist user with changing encryption password. This is my first public application for Android. You can find a source code on GitHub [2]. It is very simple, but maybe android gurus here may find what to make better.
Comments and pull requests are welcome
Thanks!
[1] http source.android.com/tech/encryption/android_crypto_implementation.html
[2] https github.com/kibab/encpasschanger
Click to expand...
Click to collapse
Sorry im noob
What will change visualy?
Or screenshot?
Sent from my LT26i using XDA Premium HD app
Thank you for this. I wanted a more simple password for the unlock, but a longer more complicated password for the decryption. You should put it on the market and charge $.99USD (or equivalent in your currency) as it's quite useful. I'd buy it
Thank you!
Actually I have registered myself as Google Play Developer, now I'm waiting for approval. As soon as my registration is approved, I will update this thread
Although I'm going to make a free and donate versions, because I believe that will help to make Android better, and people who want to say "Thank you" will buy Donate version anyway
uDroid said:
Sorry im noob
What will change visualy?
Or screenshot?
Sent from my LT26i using XDA Premium HD app
Click to expand...
Click to collapse
Nothing will change visually, hence no screenshot. What's important is that you may set strong password for decrypting the internal storage, but keep using simple password (or PIN) to unlock the screen.
P.S. I have verified that my app works on Jelly Bean too.
I have finally published an application on Google Play! Currently there is a free version, Donate version will come a bit later
The link is: https:// play.google.com/store/apps/details?id=com.kibab.android.EncPassChanger
Enjoy!
Thanks for that app, that is also what annoyed me
Thanks for this. I've been trying to work out why encryption wont work on any ROM on my HOX (dies with unable to get size of block device cryptfs), and you have given me a good lead to investigate with vdc. Information on encryption in android is sparse, and almost all threads here on XDA get no replies.
Thanks again.
I've been tempted to use device encryption recently, but there is a distinct lack of information about it, particularly on custom ROMs...
Might need to give it a go, just the lack of backup abilities might be an issue...
pulser_g2 said:
I've been tempted to use device encryption recently, but there is a distinct lack of information about it, particularly on custom ROMs...
Might need to give it a go, just the lack of backup abilities might be an issue...
Click to expand...
Click to collapse
I use CM10 on the Galaxy Nexus (maguro). Encrypted. Actually, only /data is encrypted. /system stays unencrypted. And this App works as described.
For Backup use TWRP. It asks for your password to decrypt storage.
You can then backup, restore, flash, install whole ROMs, wipe and what not.
>> I would like to see this app in Play Store <<
I should read before I post:
Kibab said:
I have finally published an application on Google Play! Currently there is a free version, Donate version will come a bit later
The link is: https://play.google.com/store/apps/details?id=com.kibab.android.EncPassChanger
Enjoy!
Click to expand...
Click to collapse
Thanks for that
btw. The encrypted /data partition lets you have two boot animations, one that is shown before code has been entered (the one in /system/media) and one after the correct code entry (the one in /data/local).
zurchpet said:
I use CM10 on the Galaxy Nexus (maguro). Encrypted. Actually, only /data is encrypted. /system stays unencrypted. And this App works as described.
For Backup use TWRP. It asks for your password to decrypt storage.
You can then backup, restore, flash, install whole ROMs, wipe and what not.
>> I would like to see this app in Play Store <<
btw. The encrypted /data partition lets you have two boot animations, one that is shown before code has been entered (the one in /system/media) and one after the correct code entry (the one in /data/local).
Click to expand...
Click to collapse
Hmm... I have i9100 (S2), so I would need to see about putting TWRP onto it...
Yeah, only data and SD are encrypted... Can TWRP cope with encrypted SD btw?
Great, it's easier than to change on command line
This should just be default android behavior
pulser_g2 said:
Hmm... I have i9100 (S2), so I would need to see about putting TWRP onto it...
Yeah, only data and SD are encrypted... Can TWRP cope with encrypted SD btw?
Click to expand...
Click to collapse
Yes, SD is encrypted too. And TWRP can only read from it after correct code entry. Don't know about the external SD though (since the Galaxy Nexus doesn0t have one).
zurchpet said:
Yes, SD is encrypted too. And TWRP can only read from it after correct code entry. Don't know about the external SD though (since the Galaxy Nexus doesn0t have one).
Click to expand...
Click to collapse
Wish I had a second phone, then I could just research this
Quite awesome. Now, can I use a strong password for encryption and then pattern lock for normal day to day use? That would be my ideal situation. I heart pattern lock!
Just trying to clarify how this works... so you keep your normal 'short' pin unlock code for unlocking the screen, but set a long code for decryption, and this code will only be requested once per boot, during bootup? Is this correct?
Thanks
How it works
Yes Sir. You are correct.
adrianblack said:
Quite awesome. Now, can I use a strong password for encryption and then pattern lock for normal day to day use? That would be my ideal situation. I heart pattern lock!
Click to expand...
Click to collapse
Unfortunately it's not possible to use pattern lock while using device encryption, Android forbids it. Patching Android framework will help, but this is completely another story and possible suggestion for ROM makers such as Cyanogenmod.
Is the 16 character Android limitation present, when using this tool? I currently use a 16 character device encryption/unlock pass phrase. I'd like to strengthen the device pass phrase some more.
I don't know if this is even possible during the device boot sequence, but being able to use a Yubikey with an OTG cable would be awesome!
RF
Hey I have installed Oreo 8.0.0 stock and Nethunter Successfully and i want to install Nexmon to the device so I can use frame injections etc. and skip the external wifi dongle.
I have a problem, when i try to compile the nexmon app I get some errors on my PC so I can't compile it... I found a pre-compiled apk on the internet and installed it and it seems to work fine...
Here are my problems, I can't install the framework/tools form the app.
I have Magisk instead of SuperSU because when i rooted the phone with SuperSU the phone gets in a bootloop.
On the nexmon site (http://nexmon.org/) my phone says it supported with Oreo 8.0.0
I think it something weird with Magisk because it is installed in a different way then SuperSU and therefore I don't have the "su" folder in root.
So my question is if someone have a tutorial or backup/rom or something i can flash or if you could help me to install the nexmon and its framework.
Thanks.
*bump*
No one ?
I also have this issue. And no, you are not at all a minority opinion.
I would like say, however, that do not expect much in re packet injection with the wlan(0)... Ideally, you are always going to want to have the ability to inject, as your post said, FRAMES. Not gonna happen, from my experience with the Nexus 5/6/Raspi. The 6p does have a different wireless card, but still, it remains an issue.
Then again, perhaps some of that may come from using encryption mode enabled, and when you use magisk, it is by definition enabled. In fact, I now can't celebrate Kali Linux 2019.2 edition of Nethunter, because magisk doesn't show up {nethunter tries to force no-verity, magisk tries to force encryption} and SuperSU results in error. I've no solution and doubt entirely it'll be found here.
hubrisnxs said:
I also have this issue. And no, you are not at all a minority opinion.
I would like say, however, that do not expect much in re packet injection with the wlan(0)... Ideally, you are always going to want to have the ability to inject, as your post said, FRAMES. Not gonna happen, from my experience with the Nexus 5/6/Raspi. The 6p does have a different wireless card, but still, it remains an issue.
Then again, perhaps some of that may come from using encryption mode enabled, and when you use magisk, it is by definition enabled. In fact, I now can't celebrate Kali Linux 2019.2 edition of Nethunter, because magisk doesn't show up {nethunter tries to force no-verity, magisk tries to force encryption} and SuperSU results in error. I've no solution and doubt entirely it'll be found here.
Click to expand...
Click to collapse
https://forum.xda-developers.com/showpost.php?p=79606695&postcount=139
In principal you're right.
Especially Oreo and the 2019.2 release, which has the exact same kernel, aren't working fully or nearly that what they supposed to.
You can use Hijacker, which works so so.
So it's your decision.. ;/
If you're still interested in a working Nethunter build, which does not necessarily has a Oreo base, you gonna flip with this one.
Although I decided to limit my participation resp contributions, I am not so egomaniac that I keep my results for me..
From now and then (max. every 3rd day), I'll look into the according "Nethunter" thread.
Best of luck
UsPdSr said:
https://forum.xda-developers.com/showpost.php?p=79606695&postcount=139
In principal you're right.
Especially Oreo and the 2019.2 release, which has the exact same kernel, aren't working fully or nearly that what they supposed to.
You can use Hijacker, which works so so.
So it's your decision.. ;/
If you're still interested in a working Nethunter build, which does not necessarily has a Oreo base, you gonna flip with this one.
Although I decided to limit my participation resp contributions, I am not so egomaniac that I keep my results for me..
From now and then (max. every 3rd day), I'll look into the according "Nethunter" thread.
Best of luck
Click to expand...
Click to collapse
Wow thanks so much for the response, and for the not-necessary information. I don't know why most everyone keeps it like a secret, but, redundantly, thanks
hubrisnxs said:
Wow thanks so much for the response, and for the not-necessary information. I don't know why most everyone keeps it like a secret, but, redundantly, thanks
Click to expand...
Click to collapse
Don't mention it.
Every time I come a across a fellow Kali (Nethunter) user, I make a caper.
And, I agree with you, logically.
Wow, Update Central
UsPdSr,
I hope that I am the first one to inform you about the new beta release for nethunter, an extention of F-droid that operates, essentially, as the Kali Nethunter App Store.
It's supposedly still in Beta, but since they accidentally updated the news feed before almost immediately deleting it (though not the link itself), I have found that
A) The apps are absolutely useful... In our context, the Nexmon app and, in case I wasn't the only one, the nethunter terminal (since the 2019.2 update, I couldn't use up to display last command etc.)
B) If they didn't want anyone to use the store, they'd have brought down the store, not just the update that announced it.
https://store.nethunter.com/en/packages/
Do you know which Nethunter works? Trying different versions, it either is missing completely, or working, but only for a few minutes.
THESE COOKED ROMS ASSUME YOU HAVE ALREADY AN UNLOCKED BOOTLOADER AND TWRP AS RECOVERY SYSTEM. You can flash them using TWRP, after wiping ART, cache, data, boot and system partitions.
FINAL RELEASE: Well... this is the final release from me and it is specifically for the WiFi model. I hope it is worth it for you. It is more stable and somewhat updated, anyway, if you use a X90F (wifi model) you will probably like it. The other versions are still up for whatever reason. Here's the link. Follow this guide by @Quardah if you are coming from a factory ROM. Go to post 46 if you can't get past the setup wizard. A barely tested (by @Nuihc88) version for the 3G (X90L) model can be found here.
NOTICE: If you find this work useful, mirror it. I won't be hosting it for free forever and it is becoming a burden to my Nextcloud installation. One would say this is a pretty much forgotten thread, but I'm seeing almost daily download activity. I'm putting the ROM files offline now and getting away from XDA for a while. Please don't DM me for the files. If you are looking for them, ask others in this thread. Good bye.
||||||||||||||||||| FROM HERE IS JUST INFORMATION YOU PROBABLY DON'T NEED |||||||||||||||||||
Spoiler: NEWS THAT ARE NOT ANYMORE.
APRIL 9, 2021: You can find in these links a new version of the cooked ROM.
The link for the updated cooked ROM is: https://centsoarer.ddns.net/s/Y8o3eoBK4Ryx5RP. This is a version with GAPPS updated: https://centsoarer.ddns.net/s/FPKjgQcmW3CHZCw. Feel free to mirror, unless you are afraid of Lenovo's lawyers, but don't forget to share the link.
My personal version... even more debloated (if you don't need chinese, japanese, korean, or russian input support/apps) and with CPU tweaks for my own usage: https://centsoarer.ddns.net/s/jcCDAgNedryGRjo
KNOWN ISSUES AND SOLUTIONS:
1) One random reboot after the first boot will happen and it is normal.
2) I'd reccommend to stay with Magisk 21.4 for a while, Magisk Manager >21.4 won't manage your extensions.
3) If you can't get past the initial Setup Wizard check post 46. Basically you have to boot into bootloader, erase the config partition and format it again.
4) Needs confirmation, but versions with signature spoofing patches seem to break Lenovo's SmartSide Bar.
JUNE 12: Fast update on the Cooked ROM and TWRP and KERNEL. They are not as universal as I implied before. Proceed carefully since they may not work four your device/firmware. Make a Nandroid backup and only flash with testing purposes.
JUNE 5: So, I know this is not what everybody who owns this tablet wants to have (that is Android 9 or 10 of course) but, in recent weeks Lenovo updated the firmware of this tablets. It still is a Marshmallow one and it still sucks big time but I took it as a base and cooked it to deliver a newer TWRP recovery with compression, a flashable modified kernel and a cooked flashable stock ROM to free the owners of this tablets from the treacherous path of making this hardware to work properly. If you want a better overall experience and are in stock firmware you just need to Unlock your bootloader, flash TWRP, Format data partition (not only wipe), Wipe Cache, Dalvik/ART, System and DATA and flash the Cooked ROM to put this tablet in a sweeter spot. For details go to post #2!
JUNE 3: Been trying to get to know some of the source code available for Cherry Trail devices and I am fairly lost at building TWRP from source. Anyway, I ported a newer TWRP recovery IMG file for the YT3-X90F (maybe L, X, Y and Z) from the TWRP image for the Chuwi Hi10 Pro tablet from here, using AIK-Linux. The result is in the second post labeled as beta, since I only tested in the YT3-X90F model, running lollipop firmware. So far, it works fine flashing ZIP archives, backing up and restoring backups. Advantages? Well, backups are way lighter if you enable compression (like half the size), higher resolution, twrp turns off the screen with a timeout and whatever made them bump from version 2 to 3. While I could port a newer TWRP version, I just wanted to have lighter backups with compression... so maybe it is what it is .
ORIGINAL POST STARTS HERE. This is general information that I collected for geeks or desperate users that bricked their tablets. When I started this post it wasn't intended to produce a cooked ROM that would include most of these hacks. You don't need this if your tablet boots to Android or TWRP. You also don't need this if you are ready to flash the cooked ROM.
(This is a lenghty post. I suggest you to navigate by section header and find the one you might need.)
There are several Lenovo Yoga 3 tablet models out there and, while some of them enjoy of prime community support as the Yoga Tab 3 Plus, this Intel Atom powered tablet is pretty much forgotten and, at the same time, users were recently buying this tablet, which is a great piece of hardware but has the most terrible support by Lenovo.
Spoiler: WHAT LENOVO TABLET(S) IS THIS GUIDE FOR?
Basically, this is that Lenovo tablet with an attached projector and an Intel Atom Cherry Trail x5 Z8500. There are several models, though, to my knowledge they vary in their code names in the last letter, the two most basic ones (2GB RAM, 32 GB ROM) are the YT3-X90F and the YT3-X90L, the former connects to the internet by WiFi and the latter being the one with LTE/Phone capabilities. There are other models, though, and they vary on the amount of RAM and internal storage. Apparently, the YT3-X90[YX] models (the 4/64 GB refresh) have some use for these firmwares we describe, but in a very specific way, if you own a Y or X model, keep reading, especially the next section.
Spoiler: EXPLAINING HOW TO FIND THE RIGHT STOCK FIRMWARE
Lenovo support has been terrible (there are no words to describe it, really), so they launched this tablet with Android 5.1 Lollipop and they maintained it for a while but were very slow to deliver Android 6.0 Marshmallow. In fact, there was already Android Nougat, when they sent the Marshmallow update. Nevertheless, the update was bad. Performance issues were always a thing and some functionality went lost in the update (less intuitive multiple windows, a crippled recents activity/screen, and a laggy overall experience). Bottom line, they launched a curated Android Lollipop 5.1 firmware with security updates until March 2016 (striked because the last lollipop update f*cks up my sensors, except the light one) and a half-assed Android Marshmallow 6.0.1 firmware.
Of course, at the time, I'm guessing most of us upgraded to Android Marshmallow 6.0.1, hoping the upgrade would fix the issues in Lollipop or with security patches in mind. The reality was that Android 6.0.1 wasn't nearly as maintained as 5.1 and security ambitions went nowhere. So, we got the upgrade all right, but at this point, both Android versions can be considered inherently insecure and we really shouldn't be using it for sensitive work.
OK, there are several Android 5.1 and 6.0 firmwares, you can recognize them because they are all over the internet typically in a compressed format. For example, this firmware hosted in androidhost.ru named:
YT3-X90F_ENG_S100265_1601281130_WW24_ROW
Is a firmware for the Lenovo Yoga Tab 3 (YT3) Pro (X90) Wifi Version (F). The ENG part is an indication of the build type, ENG is an engineer build while USR is probably a firmware for the end user (this is common now that I know a bit more about AOSP source code), it is a Lollipop firmware (S1, Marshmallow would be a S2) with update version (00265), date of compilation and a good estimate of its security patch (1601281130), the WW24 is the weekly release version of the Android kernel for Intel devices (the latest, in May 2020, being WW31 which is exactly the same as WW28 and not updated since 2016), the final part means it is the global ROM version (ROW, opossed to the Chinese version CN). This is the latest Lollipop firmware I am aware of, so, as an example, an imaginary Android Marshmallow Chinese firmware for the LTE version of the Yoga Tab 3 would look like:
YT3-X90L_USR_S200013_1610141535_WW24_CN
As an additional note the Chinese ROMS, I presume, are not trusty but they are also Google-free for what it's worth. On the other hand, they ship with a "Lenovo Services Framework" that should be as intrusive as the Google Play Services. Oh, also, baidu and yandex, and, really, any less traditional search engine can help you find a fitting firmware.
Spoiler: EXPLAINING HOW TO FLASH A STOCK FIRMWARE (DOWNGRADE TO LOLLIPOP AND UNBRICK)
I did test several firmwares, chinese and global, lollipop and marshmallow and the safest and easiest way to flash them is by using the Intel Platform Flash Tool Lite . I can't say I trust in this site, but it hosts a handy tutorial on how to use it, though, is pretty intuitive. The software exists for Mac, Windows and Linux, be sure you are in, at least, the 5.8.x version, this is important to avoid the need to install some special drivers separately as a pre-requisite. Grossly, Intel Flash Tool Lite works like this:
0) Turn off your tablet if it is on.
1) Launch Intel Platform Flash Tool Lite.
2) If your downloaded firmware is in zip format load it with the blue "Browse..." button.
2 bis) OR, if your firmware is in other compressed formats, uncompress it first. After this use the "Browse..." button to load the "flash.json" file.
3) In Configuration option select "blank" if it isn't set already. Optionally, un-tick the "On-demand flash" option to have more control of this process. Also, maybe you can use the "erase" configuration here.
4) Start your tablet in DNX mode. To do this, press Vol- and hold it, then Vol+ and keep holding both, then press the Power button until it turns on and you see the Lenovo logo and some text indicating you are in said mode.
5) Connect your Yoga Tablet with a USB cable and your Intel Platform Flash Tool Lite windows should show it as detected. Now you can proceed using the blue "Start to flash" button.
6) Keep an eye on your tablet, since some firmwares will prompt to set some more options. Unless you know what you are doing, answer "Yes" to any question.
7) Reboot and wait.
If a couple hours have passed and the tablet hasn't booted, maybe you should try another firmware.
IMPORTANT NOTE AND INSTRUCTIONS FOR YT3-X90Y AND POTENTIALLY YT3-X90X USERS: I don't know the rules in xda about linking to other forums but in certain forum there is an answered question about the Y model (the 4/64 GB WiFi only refresh) on how to flash a firmware. Instructions are the same as I gave in this section, except, apparently, you need to do it twice, first with the ENG version and the second time with the USR version except you are not using the flash.json file, this time you'll browse for the flash_factory_1st_stage.json one and the factory1st configuration in fastboot. It is not clear what are the consequences of not doing it this way or what if you combine different firmware versions (it would be interesting to have a tester here). Notice please, these firmwares are marked for the YT3-X90F model. So, clarifying:
1) Follow the instructions above to flash the YT3-X90F_ENG firmware.
2) Power off your tablet.
3) Boot into bootloader (not in DNX, you need to boot into bootloader by powering on while holding Vol+).
4) From the YT3-X90F_USR firmware folder use Intel Platform Flashing Tool Lite to load the flash_factory_1st_stage.json and select the factory1st configuration.
5) After flashing the USR firmware, reboot and you should be good to go.
METANOTE: This wasn't tested by me, please do this only when you are hopeless with your hardware. This is just an educated guess but I bet it works the same with the YT3-X90L (the LTE version 2/32 GB Yoga Tab 3 Pro) and the YT3-X90X (the 4/64 GB refresh).
ALTERNATIVE WAY TO FLASH A STOCK FIRMWARE (ADVANCED USERS, requires fastboot)
Well, there is no need, really, to use that Intel tool. In my search for a lollipop firmware (I wanted to downgrade from Marshmallow) I found the firmware YT3-X90F_USR_S100195_1512052308_WW24_ROW in www.firmware247.com or www.androidfilehost.com (IMPORTANT: please read the note on downgrading to Android 5.1 Lollipop in the note at the end of this section). This firmware was special since, if you are in Windows and have fastboot executable ready and in place, you can run a script (run_me.bat) in the Windows terminal (CMD) or Powershell to flash the firmware semi-automatically. I think this firmware was modified, though, since I found differences in the boot.img when compared with stock firmwares. This script is credited to XDA members @ionioni and @joesnose and you can replicate its steps if you:
0) Turn off your tablet if it is on.
1) Start your tablet in DNX mode. To do this, press Vol- and hold it, then Vol+ and keep holding both, then press the Power button until it turns on and you see the Lenovo logo and some text indicating you are in said mode.
2) Connect your tablet to your fastboot enabled PC using a USB cable.
3) Input "fastboot flash osloader loader.efi"
4) Wait 5 seconds to be sure the loader flash finishes.
5) Reboot into Bootloader. If you don't know how, one way is to hold Vol+ and Power on your tablet.
6) Input "fastboot oem unlock" and confirm using Vol keys to select the right option and the Power button to enter it.
7) Input "fastboot flash system system.img"
8) Input "fastboot flash boot boot.img"
9) Input "fastboot flash recovery recovery.img"
10) Input "fastboot flash bootloader bootloader.img"
Follow your instincts, since I don't know if these IMG files are always named the same. You can get these IMG files from downloaded sources or dump them yourself using dd command.
NOTE ON DOWNGRADING TO ANDROID LOLLIPOP 5.1: So, one of my main concerns has been to go back to Android Lollipop. There is a last version of Lollipop from where you can upgrade to Marshmallow with a security patch from March 2016. Nevertheless, you MAY end up loosing other sensors except the light one. If this happens, you need to use a complete firmware flash using Intel Platform Flash Tool Lite. In my experience, some boot images are not compatible with other weird partitions like country or misc.
Spoiler: TWEAKS ALREADY IN THE COOKED ROM
The first boot takes some time even amounting for the time of the setup itself. By the time you are in the launcher tapping on app's icons you think there's nothing wrong with our device, but after some apps are in memory, you notice some lag. You think "OK, it is updating, but soon it'll settle", but it does not. So, you reboot again after updates and fire up a terminal emulator and connect to your tablet using a USB cable with USB debugging turned on and issue a free command to find something like this:
Code:
total used free shared buffers
Mem: 1950372 1820964 129408 0 7756
Swap: 524284 10740 513544
Total: 2474656 1831704 642952
Which means you have a total of ~2.5 GB (this is the 2 GB model). So, did I download that extra half GB of RAM or Lenovo was feeling generous? Well, no. The issue here is Lenovo built the kernel with zRAM support which is a technology included in Linux that reserves space in RAM to quickly compress and uncompress pages of data exceeding our physical amount of RAM installed (2 GB). This is not Virtual Memory as in a swap file/partition or Windows' Page File inside storage media. zRAM literally reserves a fixed amount of physical RAM space (blocks) to expand it by compressing data. The consequence is you loose "fast RAM" (THE RAM) and gain some "slow RAM" (the zRAM). You also sacrifice some CPU power to compress/decompress data and, with this, some battery juice is also lost.
That does not sound like a terrible trade-off for a RAM-limited device, one would think. Another interesting thing would be WHEN to send this piling data in "fast RAM" to the compressed space and WHEN to get it back. Two parameters control the WHENS, one is called "swappiness" (when to send it to the compressed space, the "slow RAM") and the other may be the "vfs_cache_pressure" (when to uncompress it and send it back to the "fast RAM"). And this is where the main problem is, really, because the kernel, Linux, is pressing the RAM constantly to send some less prioritary data to "slow RAM" and, at the same time, is trying constantly to send compressed data back to the "fast RAM". Summarizing, this kernel behavior is practically minimizing the fast RAM amount and usage while maximizing the "slow RAM" usage. This is nuts, by default a swappiness and a vfs_cache_pressure of 100 are not even default for servers, these parameters extremely prioritize that processes can get done no matter how slow they get, and they are even more nuts when Android is designed to work without swap space.
What that free command is telling us is the tablet is using the "slow RAM" even when we only just turned it on. Fortunately there are two ways to fix this problem: one is to completely disable zRAM, the other one is to use ZRAM a whole lot less by tweaking the swappiness and vfs_cache_pressure parameters. This can be easily done with the following sentences in a rooted tablet:
Code:
# echo 5 > /proc/sys/vm/swappiness
# echo 50 > echo 5 > /proc/sys/vm/vfs_cache_pressure
Or, to regain the whole fast RAM:
Code:
# swapoff /dev/block/zram*
One caveat of the first method, reducing swappiness, is there is still a lot of RAM (one quarter of the whole RAM in a 2 GB device) reserved as "slow RAM".
SOME ROMS DID NOT ENABLE KERNEL SAMEPAGE MERGING, UNFORTUNATELY
Additional to the sorry implementation of zRAM, some firmwares support a fabulous Linux tool to reduce RAM usage called Kernel Samepage Merging (KSM) but they don't use it by default. This software runs at kernel level, so, it really is CPU-wise inexpensive and, opposite to zRAM it can actually recover some RAM usage by reducing the amount of data flagged as redundant in physical RAM by merging it. KSM is good for you and you should have it always enabled by issuing the following command as root:
Code:
# echo 1 > /sys/kernel/mm/ksm/run
STOP WRITING AND FIX MY RAM! PLEASE!
Well... are there any people interested on this? With the above information you can write a script to execute at boot. Something like this should work in any version of the firmware:
Code:
#!/system/bin/sh
# Mount system as rw
busybox mount -o remount,rw -t auto /system
# Tweaking swappiness in zram
echo "5" > /proc/sys/vm/swappiness
echo "50" > /proc/sys/vm/vfs_cache_pressure
# Activating Kernel Samepage Merging
echo 1 > /sys/kernel/mm/ksm/run
# Remount system as ro. noatime option for faster and volatile system
# busybox mount -o ro,remount,noatime /system
busybox mount -o ro,remount /system
exit 1
Or, you can unpack the boot.img and modify the init.cht_ffd.rc (lollipop) or the init.r2_cht_ffd.rc (marshmallow) files to write these values as default... or, if there is interest for something easier, I can produce this boot.img files for you to flash using fastboot.
ROOTING THE LENOVO YOGA TAB 3 PRO (YT3-X90[FL])
Here I am not gonna write a lot. Instructions were given in this thread. I'd only recommend to put vm.targetutilization at 0.8 top 0.85 in system/build.prop
After rooting, debloat your firmware. I use the app "/system/app mover" from Fdroid to convert to user apps and uninstall them. Also, if rooting is not your cup of tea, you can install AppOps software to freeze all those apps that you don't use regularly. Also, I couldn't patch my services.jar for Signature Spoofing with Nanodroid patcher in the most recent lollipop firmware, but it did work in Marshmallow... anyway I'll do it manually.
ARE YT3-X90F AND YT3-X90L FIRMWARES INTERCHANGEABLE?
I own a WiFi only device (YT3-X90F) so I can't assert they are interchangeable. If I owned the LTE version and use a WiFi firmware I would expect to loose LTE functionality. Now, on the other direction is more interesting because I've been using a LTE firmware version for weeks (as a matter of fact, the one joesnose linked in his How-To debrick this tablet, flashed with the instructions I posted for advanced users it even updated to recent 2020 firmwares). The only tweak you need for this to work well is to add "ro.ril.disable=1" in the build.prop file. So, yes, firmware for the LTE version work in the WiFi version but kind of not vice versa.
Spoiler: YT3-X90(FL) UN-DEVELOPMENT
No news here. All capable people interested on developing for this device are all done with Lenovo and their attitude against Open Source. Don't expect your situation to change.
I'm happy to know there are still a couple of developers interested on this device. I won't cite them by linking their names but they are OOEvil and alquez, the first guy is trying to make a Generic System Image (GSI) ROM compatible with our tablet, I don't know the details so I wouldn't go further. Alquez has been active in this thread and, while he is trying to figure out how to build a kernel, he believes the best way to start having some alternative to official Lenovo firmware is by using a firmware kernel (a prebuilt kernel) to, first, build a more up-to-date TWRP recovery.img and from there try to build CyanogenMod 13, which was based on Android Marshmallow 6.0.1. My guess is newer Android versions wouldn't work if we can't build the kernel from source.
PHOTO ALBUM OF YT3/X90Y BIOS
This photo album documenting every screen option in the BIOS of the Yoga Tab 3 Pro may or may not help someone, but it contains a lot of useful hardware information and guidance for those attempting to boot something else than the original Android 5 or 6 firmware. Using this options, that are accessible through F2 at boot with an attached USB keyboard, you could try Linux distributions on the tablet or even attempt to run Windows, @alquez informs it works fine with a recent distro but the mainline kernel is lacking touchscreen and battery support. This is absolutely his work and he asked me to share it. I hope it serves someone. It is hosted in a rather obscure website but it was the only reasonable placeholder I could find for the 321 photos.
Hope this helps someone, I just didn't want to keep it to myself. Have a nice day!
Just remember, if your tablet is 3G capable I strongly suggest that you modify the line "ro.lenovo.tablet=wifi" to "ro.lenovo.tablet=3gdata" and remove the line "ro.radio.noril=true" to your build.prop file in /system. To do this you can use the section Build.prop Editor of the Kernel Adiutor app or you can do it manually if you have already a method to modify system files. If you do not use mobile data at all, you may leave the build.prop as it is, you'll save a lot of battery by using only wifi.
Spoiler: Some old info here, but maybe useful
ONLY FOR TESTING: Cooked ROM, newer TWRP and tweaked kernel
ONLY TRY THESE FOR TESTING PURPOSES, THE TWEAKS ARE ALL SAFE TO USE BUT ONLY FLASH FOR TESTING PURPOSES, PLEASE. FIRST, TRY TO USE FASTBOOT TO BOOT THE boot.img FILE WITHOUT FLASHING: IF IT BOOTS GO AHEAD AND TRY THE OTHER FILES (fastboot boot boot.img). THE TWRP IS NOT AS STABLE AS THE OTHER ONE HERE AT XDA BUT ALLOWS TO USE ZIP COMPRESSION IN BACKUPS. I AM NOT GONNA BE AROUND. IF YOU TRY SOMETHING MAKE A BACKUP FIRST. THIS DEVICE IS MESSY AS F*CK.
Spoiler: Some old info here, but maybe useful
I wrote a very detailed guide about these files I uploaded to my Nextcloud that include the newer TWRP-3.0.2, a TWRP flashable Cooked ROM and a separate kernel (boot.img) in case your system is already setup, but the post went to some XDA void and didn't upload. These are based on the YT3-X90L latest firmware, but they work on the X90F model too. The TWRP should work with Lollipop and Marshmallow firmwares.
I can't write everything again, so, the kernel contains better management of RAM and emmc (internal) memory, a 256 MB zRAM space instead of 512 and a more conservative approach to LowMemoryKiller.
The cooked ROM includes the described kernel and debloated apps, it's already rooted with Magisk (you can unroot with Magisk Uninstaller), an updated Busybox build, su.d support (I plan to use it with AFWall+), zipaligned apps, etc. It is for the X90L but possibly works for the other Yoga Tab 3 Pro models. It works for the X90F but it will reboot once after the first boot because the RIL configuration times out. To install the cooked ROM you need to:
0) Know that by doing this you will loose pretty much everything in your tablet. You start from scratch if everything goes smooth, if not you could possibly end up with a system without an OS. The usual stuff when you are customizing your system.
1) Boot into TWRP and make a Nandroid backup. IT IS IMPORTANT because @joesnose had problems with a "random reboot" and lost Bluetooth/WiFi after it. I am trying to look into this. The only difference is his tablet has 4 GB RAM and probably a different firmware.
2) Wipe cache, Dalvik/ART, System and Data in TWRP - Wipe, Advanced Wipe menu. If your tablet is encrypted, or in factory firmware you also need to explicitly use the button "Format Data partition" and confirm writing "yes" in the format procedure prompt. You will loose any configuration made to your tablet.
3) Install the superr_stockMM.zip wich is flashable by selecting the file from your Internal tablet memory, using the Install button in the main TWRP interface.
FOUR IMPORTANT NOTES TO COMMON ISSUES:
If you come from a stock firmware your data partition is encrypted. You need to pass a blank password in TWRP to continue to use the custom recovery. You also need to format data partition before flashing the cooked ROM.
If your tablet is WiFi-only I strongly suggest that you modify the line "ro.lenovo.tablet=3gdata" to "ro.lenovo.tablet=wifi" and add the line "ro.radio.noril=true" to your build.prop file in /system. To do this you can use the section Build.prop Editor of the Kernel Adiutor app or you can do it manually if you have already a method to modify system files. In Lollipop firmware you use "ro.ril.disable=1" instead of "ro.radio.noril=true" to get the same effect: sort of a conversion to WIFI-only tablet from LTE models. I'd argue this is useful to do if you are gonna be without LTE connection/service for long periods of time and I can think a couple of other uses.
Do not use stock Lenovo launcher unless you uninstall Magisk... they are incompatible for reasons I don't care to know and the Launcher will constantly FC (it is a pain in the arse).
If you are still expecting better performance I am sure there are some tweaks left in RAM management but it wont go too much further in 2 GB devices. Instead, you may consider to lower your display resolution and pixel density to something reasonable as 1400x2240 or even 1200x1920 maintaining the same aspect ratio. To do this you do not need to have root but you need to interact with the tablet using ADB. First change the size of your display:
Code:
adb shell wm size 1400x2240
Then adjust your density:
Code:
adb shell wm density 260
If still is not enough you can go even further with 1200x1920 and 224, use the same method to go back to stock with 1600x2560 and 300 to 302. This won't need a reboot but will probably cause an inconsistent UI that will lead to FCs and random reboot. You can just reboot after applying these tweaks. Unless you are really sight-gifted you won't notice a lot has changed but you will be dealing with 2.x Mpixels instead of 4.x Mpixels and that will help with your overall performance as well as your battery life sacrificing a pixel count that most of the people wouldn't even notice. If you did this correctly, in the next boot sequences you'll notice an offset on the Lenovo orange logo.
It is important to say that your display supports 1600x2560 pixels physically, but I'm assuming the GPU has no dedicated RAM and uses the device's, so, by reducing the quantity of pixels the GPU needs to deal with, the pressure on the device's RAM is also reduced.
EXTRA TIP: If boot annoys you just delete /system/media/boot.wav, bootanimation.zip and shutdownanimation.zip and you'll get a silent boot and the generic android boot animation.
Hope you enjoy your tablet!
TWRP-3.0.2.0- BETA: Again, this is not a flashable zip. Uncompress first and test the recovery system using "fastboot boot twrp_yt3-x90f_beta.img". If everything works for you, you may want to flash it permanently rebooting to bootloader and flashing with "fastboot flash recovery twrp_yt3-x90f_beta.img". Remember I did not test this in Marshmallow yet.
FEATURES:
- Fixed RAM issues (swapiness 10, vfs_cache_size 50 and disabled dynamic low memory killer tweaks and minfree values).
- Reduced zRAM size to only 256 MB.
- Tweaked interactive CPU scheduler to use other than min and max frequencies (but still responsive). The tweaks are based on the Advanced Interactive Governor Tweaks Guide. This may save battery life.
- Max frequency capped to 2.08 GHz (this is not great if you are a gamer). This tablet throttles when using max frequency for a long time, so, to save battery and keep it cooler I tweaked the CPU to run slower.
- Tweaked I/O schedulers to use deadline governor and read ahead cache to 640 kb (used benchmarks to get to this value).
- Force encryption disabled (to avoid applying ionioni script after flashing). Still needs to format data partition. You can encrypt your data partition later through Configuration -> Security user interface.
- Implemented native init.d support (not su.d anymore and no need to root the main OS).
- Busybox updated.
- Rooted with Magisk by default ( you can use Magisk uninstaller to unroot).
- Debloated apps. I also deleted Lenovo User Experience Program which was asking for root privileges even when you don't opt in to the Lenovo UE Program at setup wizard. I find this behavior shady.
-Multi-window mode is available in Developer Options and needs to be activated by you. In this mode if an app is compatible with multi-window mode you can double-tap on its title bar to enable Window mode. This function was more transparent in Lollipop firmware but it is still there in Marshmallow firmware if you change the build type to userdebug instead of user in build.prop (that's how I enabled it in the Cooked ROM).
- There are also other tweaks in VM and KSM.
And that's it, I'm not trying to change a lot, only the fundamental issues. But I suggest some other tweaks up there.
Such a shame. I love my Yoga Tab 3 Pro. Great hardware. But the software. Thanx anyway for your work.
Very nice write up. Thanks.
joesnose said:
Very nice write up. Thanks.
Click to expand...
Click to collapse
You're welcome. Thanks to you, while learning about this hardware your username pops everywhere.
jahfaby said:
Such a shame. I love my Yoga Tab 3 Pro. Great hardware. But the software. Thanx anyway for your work.
Click to expand...
Click to collapse
It really, really sucks. Let's hope something interesting happens after these strange and recent updates.
CENTSOARER said:
V1: The zip name boot_mod_mm.zip is based on the latest boot IMG provided by Lenovo. You need to first uncompress and flash it using fastboot (this is not a TWRP flshable zip). If you are uncomfortable flashing, you can test it only by issuing "fastboot boot boot_mm_march20_mod.img" once uncompressed, or, if you feel fine using it you can flash it permanently by using the command "fastboot flash boot boot_mm_march20_mod.img". This boot IMG will only work with Marshmallow firmwares in both YT3-X90(FL).
FEATURES:
- Fixed RAM issues (swapiness, vfs_cache_size and low memory killer tweaks).
- Reduced zRAM size to only 128 MB.
- Tweaked interactive CPU scheduler to use other than min and max frequencies (but still responsive). This saves battery life.
- Max frequency capped to 2.08 GHz (this is not great if you are a gamer). This tablet throttles when using max frequency for a long time, so, to save battery and keep it cooler I tweaked the CPU to run slower.
- Tweaked I/O schedulers to use deadline governor.
- Force encryption disabled (it's unnecesary to apply ionioni script now). Still needs to format data partition. You can encrypt your data partition later through Configuration->Security user interface.
Click to expand...
Click to collapse
Thanks for this. Going to take it for a spin.
joesnose said:
Thanks for this. Going to take it for a spin.
Click to expand...
Click to collapse
Please, please provide feedback and don't forget to wipe caches.
alquez said:
"No news here. All capable people interested on developing for this device are all done with Lenovo and their attitude against Open Source. Don't expect your situation to change."
https://github.com/intel/ProductionKernelQuilts this repository containts patches necessary to create base 3.14.55 and 3.14.64 uefi/cht-m1stable kernel tree. The same tree that was butchered by Lenovo in their OPEN_SOURCE "release".
Check this file https://github.com/intel/ProductionKernelQuilts/blob/master/uefi/cht-m1stable/ChangeReport.md and the WW24 part in the "YT3-X90F_ENG_S100265_1601281130_WW24_ROW" will become more clear
Quilt manual: https://elinux.org/images/7/74/Maintaining_Multiple_Android_Linux_Kernels_at_Intel.pdf
If someone would be looking for a good piece to start: the best would be to recreate 3.14.55 or 3.14.64 from the quilts, use the x86_64 defconfig and build a kernel which can be booted. In order to test this, the best solution is to repack TWRP with the new kernel and do "fastboot boot" without flashing, until it boots and the touch screen is working. There's no other way i'm afraid.
I have prepared complete photo documentation of UEFI Bios, i can share, currently moving to different google photos account. Its over 300 photos.
Please, set up a Discord channel if you want to proceed. The first month will be quite boring and daunting because it's going to be build -> repack -> boot -> rant
Click to expand...
Click to collapse
In my defense, when I wrote that sentence was after taking a peek on your github profile, I figured you were just done with the Yoga Tab 3 Pro. I am really, really glad you're still trying and I recognize you are very capable of changing things for this device. I appreciate the sources you link but I am afraid I am useless as a developer, partly because of a lack of time and partly because of a lack of adequate training. I will try to help as much as I can, though. Thanks for the post.
alquez said:
No worries, however if anyone is interested how to actually crunch this one: we have a working prebuild kernel which can be pulled of boot image, and we have a working TWRP, however it looks like TWRP wasn't actually built from source, but cooked using android kitchen so we're still missing a device tree, which in my opinion is a good place to start, because you can use prebuilt kernel to build recovery and lineageos/aosp (it's deprecated but we're talking about android 6 aka cm-13.0/lineage 13.0). If I can create a most basic device tree which is capable of building recovery from scratch useing binary kernel and modules, i'd say were' good, because the next part would be adding more binary blobs from the official software, and we can skip the kernel source part for now until we have lineageos build 13 working). I started experimenting on xiaomi latte tree because it wasnt split like Z00A. It's not gonna be a proper port but it should work from now (i think)
@joesnose did you cook or compile TWRP? It's important
Ok, I'm at the stage i have two folders. The one is unpacked working TWRP, the other one is unpacked compilation i'm building, which means im able to build TWRP from source with binary kernel, but it's not working yet. The goal is make the left one look like the right one by adjusting various parts in BoardConfig.mk and copying files.. If someone has right partition sizes for BoardConfig.mk that would be really helpful, the values i calculated suck and don'y boot yet
Click to expand...
Click to collapse
Uhmmm, I've been there and took some notes with some "GNU shell Fu". What sizes are you using right now?
And regarding the WW part of the name I've noticed the recent updates are marked as WW17 opposed to WW28 which was the latest stable with any changes. Any idea why Lenovo used WW17 to update the Yoga Tab 3 Pro recently?
alquez said:
update, ive managed to boot vanilla android-x86 x64 6.0.1 build without touching the kernel yet and different TWRP (3.1.1.0) with kernel swap
Click to expand...
Click to collapse
Geez, I was excited because I read Ubuntu booted on this hardware but then I realized it was the Yoga 3 tablet but not the Yoga Tab 3, goddamnit. Keep up the good work!
alquez said:
Um Ubuntu 20.04 boots with working accelerometer so the screen rotation works + wifi, and probably audio i forgot to play youtube video, the stuff missing is battery, touchscreen and projector.
To test it you need to connect a usb hub using usb otg, put ubuntu and a keyboard in the hub, boot, and press f2 really fast if you haven't enabled slow boot yet. You can even boot
Xubuntu to ram and remove flash drive. It's a pc architecture after all and most of the processor related stuff is in the linux mainline since 4.11
Recently i was checking why the Windows 10 installer crashes on ACPI Error.
Click to expand...
Click to collapse
Oh, I will have fun doing this kind of stuff at the end of the year. It must run swiftly with i3, provided you won't get touchscreen support.
alquez said:
Geting TS and a battery running is a mandatory, the next is the projector. The rest is pretty much working. I'm building generic celadon x86 atm and the beast is huge it's like 18% now after two hours on -j8 on i7. Maybe we can give this old monster a new life
edit:
And i need to add 480gb drive ;/
Code:
/dev/sdc1 229G 210G 6,7G 97% /home/android
Click to expand...
Click to collapse
I am afraid those are the peripherals that will keep you in 3.14.55/64 Linux, at least for a while , unless you know something more (wouldn't be surprised).
Are those GB for source code or for cache? Both? Jesus... the thing is huge but reading the unpacked boot.img makes much more sense now.
It was ionioni who made the twrp for the device. I dont have the foggiest how he did it.
---------- Post added at 01:23 AM ---------- Previous post was at 01:18 AM ----------
Wow! I missed lot, looks like you have made some serious progress here. very well done.
alquez said:
I contacted my friend and he told me to compare these two folders:
https://github.com/alquez/lenovo_yt...l/cht/arch/x86/platform/intel-mid/device_libs
https://github.com/torvalds/linux/tree/master/arch/x86/platform/intel-mid/device_libs
the new files in "lenovo tree" are the modules we're after, mostly and it's a place to start
I need to ask inioni about twrp.
Click to expand...
Click to collapse
I will guess it was ported from the Yoga Tab 2. I will edit this post soon.
alquez said:
Nice! There's big chance the modules are reused somewhere. We can compare these. I think the two folders in
https://github.com/alquez/lenovo_yt3_x90_osc/tree/master/kernel/cht/drivers/input/touchscreen
which are missing from vanilla tree are two separate drivers and one is for "any pen" driver. Can you ask someone porting modules recently
to help us refresh my memory
[edit]
I've got in touch with TeamBliss of BlissRoms , they are working on cherrytrail tree
Click to expand...
Click to collapse
Nah, I couldn't confirm it was ported. A lot of posts were removed when XDA enforced the GPL measures to its developers.
About BlissRoms, it just makes sense they are working on Cherry trail. I hope you and those guys can achieve something soon. I mean, it's a 2 GB RAM device but the display, projector and dolby audio system are worth for a better fate than Lenovo's plans.
alquez said:
4GB of ram 4 cpu cores, Hardware virtualization support, fast gpu and fast emmc memory. It's a beast, way ahead of it's time.
Click to expand...
Click to collapse
Well, I have the 2 GB RAM model, so my expectations are conservative. Anyway, don't believe I'm a hardcore user, so it's plenty enough for me, considering I won't even flash Google apps. I am now settled with Lollipop, since I need apps not getting killed by damn Doze. It is a shame how OEMs can limit a device like this one. Crond, init.d, bad zRAM, shell, even busybox... frequently the OS is crippled. I read somewhere Doze can be disabled in build.prop or something but one thing I just hate is the recents screen in Marshmallow firmware (my God, is terrible!) and can't be easily changed for something like OmniSwitch. I mean, for a mobile device you have an unusual architecture, why limit it further? Damn, I wish BlissRoms come up with a working build.
Hey, @alquez, have you tried Linux 5.7 on the tablet? I saw this article and seems like the touchscreen may work with the next mainline kernel release. I mean, right now is on RC7, should be stable enough to compile and try (I'd try it, but can't get to my workstations thanks to the virus).
EDIT: Ah... I was looking into my device and it comes with a HiDeep touchscreen (cat /dev/input/event3), the linked news is for the Goodix driver / devices. At least, I guess, it will attract others to this platform... anyway, I was wondering and also confused, shouldn't touch screen work with the hideep driver using this config already?
Thanks for the new feel.
This is great, glad to see a developer picking up this tablet. It's a fine machine with an unfortunately small user base and has never really seen any development apart from ionioni s efforts and he didn't even own one, lol.
Edit: *Thank for the new twrp * auto correct!
I love this device! For me it's the perfect device for vacation just because of the projector!
I am so happy that you guys are working on it again. the ram and display tweak works like a charme for me. Had to reset my background screen though
thx for all your help. As soon as you guys have light rom, i'll install it on my 2GB device.
hello how to flash your twrp please ?
can someone upload adb drivers for the yt3-x90f please ? because i try to flash in dnx fastboot mode but commands don't work, even "fastboot devices" don't show me the yoga tab 3 pro