[Upgrading, Modifying and Unlocking] DebTab:
Lag, no su access

Thanks for this short guide and thanks to DooMLoRD for the rooting kit.

I tried this on a cheap new Q88 MID A13 tablet the other night and it ran nice and smoothly first time, and got SuperUser on there. However, once I tried actually using the tablet for anything the next morning, everything was slow as ****.

With no apps open, a single screen-tap will often not register for most of a minute (if at all), menus would then take just as long to open, and everything from the browser to adobe reader to the app launcher itself, running on their own, would frequently generate a popup error saying that it had stopped responding, asking to wait or close the app.

It also gets quite warm in the corner with sockets & buttons during operation. I'm not sure if that's because something is running on the processor (I thought it was located more towards the middle) or something else, so I tried switching it off and sticking it in a freezer to make sure nothing was overheated, but that made no difference.

The closest forum post I've found so far was this: androidforums dot com/galaxy-s2-x-all-things-root/675647-phone-app-lags-freezes-after-root.html (I'm not allowed to post links here yet), where a user experienced lag after rooting, until re-flashing their firmware, but that was for completely different hardware.

Update: a couple of days after supposedly rooting it, this lag went away with no indication as to why.

I have now tried to install Debian, only to find in the first step that something has gone wrong in rooting the device. SuperUser is installed, but when I go into a terminal application and type in su, I get "Permission Denied", without any prompt to allow it.

I tried setting the SU app to auto-allow, no difference. I tried running DooMLoRD's rooting script again, and again it didn't give any errors and claimed that it ran successfully, including changing permissions, but that didn't make a difference either.

Update 2: I've read mention that there should be an option in Developer Options in the Settings menu to allow su over ADB, but anything to do with root permissions seems to be completely missing from there.

Update 3: I found someone who seems to have a similar problem to me (unresolved): tabletrepublic dot com/forum/android-hacking-tweaking/rooting-svp-allwinner-a13-tablet-4680.html

Update 4: One friend suggested that I try to get a newer version of android flashed on there that might fix rooting it, but before I could even get to backing up its current firmware, Windows told me that I'm plugging in an unrecognised USB device. It seemed that the brand new (cheap tat) micro-USB cable that shipped with the tablet wasn't quite up to the task of transferring data reliably, so I replaced it.

Update 5: Now I've got a back-up of my firmware by using the 'Uberizer' toolkit, but still neither DooMLoRD's rooting script nor one included with Uberizer, the latter apparently tested & working with Android 4.0 on an A13 device, could get my tablet rooted properly. Thankfully, Uberizer at least includes a 'root check' application for troubleshooting.

Here is my output after attempting to root the tablet with DooMLoRD's script:

Detailed Results:

Root Access is not properly configured or was not granted.

Superuser.apk - com.noshufou.android.su - version 3.0.7 is installed!

System Environment PATH: /sbin /vendor/bin /system/sbin /system/bin /system/xbin

The adb binary is set to default shell user access as root

Standard su binary location: ls -l /system/bin/su:

-rwsr-sr-x root shell 22364 2008-02-29 02:33 su

Standard su binary location: ls -l /system/xbin/su:

lrwxrwxrwx root root 2014-05-12 16:43 su -> /system/bin/su

Alternate su binary location: ls -l /sbin/su:

/sbin/su: Permission denied

Alternate su type binary location: ls -l /system/xbin/sudo:

/system/xbin/sudo: No such file or directory

SU binary not found or not operating properly

and after attempting to root it with the 4.0 ICS rooting script included in Uberizer:

Detailed Results:

Root Access is not properly configured or was not granted.

Superuser.apk - com.noshufou.android.su - version 3.1.3 is installed!

System Environment PATH: /sbin /vendor/bin /system/sbin /system/bin /system/xbin

The adb binary is set to default shell user access as root

Standard su binary location: ls -l /system/bin/su:

-rwsr-sr-x root shell 22364 2008-02-29 02:33 su

Standard su binary location: ls -l /system/xbin/su:

lrwxrwxrwx root root 5692 2012-11-27 21:28 su

Alternate su binary location: ls -l /sbin/su:

/sbin/su: Permission denied

Alternate su type binary location: ls -l /system/xbin/sudo:

/system/xbin/sudo: No such file or directory

SU binary not found or not operating properly

Maybe someone can help me to understand this better, but it seems there's not much difference, just showing that they were installing different versions of su, and I don't know yet why they didn't put it in those other locations. Any hints?

It seems that I do get root access via Uberizer's ADB shell though, which seems to be enough to install Debian side-by-side with Android, yet then of course be unable to actually use it on the tablet due to lack of root access. :mad:

Build info:

Android Version:

4.1.1

Baseband Version:

jellybeanV1.2

Kernel Version:

3.0.8+

Build Number:

nuclear_pfdq88d-eng 4.1.1 JRO03C 20130920

Dead thread is dead.