How to root your Hudl 2

[Guest PaulOBrien]

The following post contains information on how to root your Tesco Hudl 2.

MoDaCo / I take no responsibility should anything bad happen to your tablet, regardless of how / why it happens. You should be aware that rooting your device may void the manufacturer's warranty and is a risky operation. If you don't feel confident following the steps in this post, do not proceed.

Before you start, read through all of this post. Then read it through again. Failing to follow the steps correctly could lead to your device being rendered completely unusable (bricked). See above.

It is advised that you do NOT install any OTA files without checking here first that it is safe to do so!

What you need in order to use this root solution

To use this root solution you need a Hudl2 (obviously), a Windows, OSX or Linux computer and a microUSB cable. Your Hudl2 MUST be running software version '20140924.194555' or '20141009.191216', detailed at the bottom of the 'Settings -> About' screen.

Does my tablet version really matter?

YES. If you attempt to use this root solution on a version other than that detailed above, there is an extremely high possibility you will brick your device. And that will be bad. The hudl 2 is great, but it's too thin to make a particularly good doorstop.

How it works

Normally when I create a root solution I prefer to use one of two approaches. The first is a 'superboot' image, which is loaded via fastboot and automatically roots the device. Unfortunately this is not possible on the hudl 2 as the 'fastboot boot' functionality is stubbed (not available). The second option is to build a custom recovery that allows flashing of update zips, which is flashed using 'fastboot flash'. Unfortunately this is not an option either - although fastboot flash is supported on the device, the recovery partition appears to be checksummed in some way. My attempts thus far to create custom recoveries have failed to boot, which is unfortunate.

With this in mind I have instead built a custom system image for flashing via fastboot. It is completely stock apart from the addition of Chainfire's SuperSU root application. Granted, it's not the ideal way to root but for now, it works. I will continue to investigate alternative approaches.

The dangers of rooting

As I found out with my first bricked device, hacking around on the Hudl 2 is dangerous. If the device won't boot (perhaps due to a problem on the system partition) and ADB is not available, then there is no way to recover. Droidboot, which is used to flash the device for this root, is only accessible via 'adb reboot bootloader'. The recovery image can be loaded by powering on with the volume up button held, but this will only flash zip files signed with a key we do not have. Powering on with volume up and down buttons pressed produces a message on screen saying 'entering bootloader', but the bootloader (at least in the form accessed via 'adb reboot bootloader') is never reached. I'm not sure if this is a bug or intentional, but it's certainly not helpful. If you are going to hack your hudl 2, be extremely careful.

Reverting to stock

The quickest way to revert to effective stock is to use the 'unroot' option in the SuperSU app.

Custom ROMs

Due to the fact that I am currently unable to get custom recoveries booting, I am also unable to build TWRP or CWM for the device, which severely limits custom ROM options. In addition, I haven't yet tested flashing a custom boot image as this is almost certainly going to have the same issue as the recovery images and is a sure-fire way to a brick the device.

Download

• Rooted Image for 20150106.154003 (r1): DOWNLOAD (ROMraid) - ZIP MD5: 837b0a8beb5c0e21a6521b94c68d1fe0 / Image MD5: 4feb49cd6845aebcef96f05048bd6062
• Rooted Image for 20141009.191216 (r1): DOWNLOAD (ROMraid) - ZIP MD5: 3861a3769b08b671fd86c8d9d748e4a2 / Image MD5: 6d424b3f32c1b0fe94f1e841d5042e63
• Rooted Image for 20140924.194555 (r3): DOWNLOAD (ROMraid) - ZIP MD5: 9c58e25f5d9786555dc0f5e5f777fda1 / Image MD5: 9329255e0928c69e3ba6f5e4cde7fc6c
• ADB / Fastboot tools: DOWNLOAD (ROMraid) - ZIP MD5: 299162039f527bc361221fb526976fc7

How to root

To root your device, follow the following steps:

• Ensure your device is fully charged. This is a safety net really, but good practice. It gives you time if something goes wrong. At the very least i'd recommmend 50% battery. If your device powers off for any reason or the flash is interrupted, your hudl 2 is toast.
• Ensure USB debugging is enabled. In 'Settings -> About', tap the 'build number' like a madman until a message appears stating developer mode has been enabled. Then use 'Settings -> Development' to enable USB debugging.
• Plug the device into your computer using the microUSB cable. A message will pop up on screen asking you to authorise the connection.
• Download and extract the zip file above to a directory on your computer. If you don't have ADB / Fastboot already, you should also download and extract that.
• Open a command prompt / terminal window to the location where you extracted the files
• ON A WINDOWS PC: enter 'adb-windows reboot bootloader', when the device has rebooted to bootloader enter 'fastboot-windows -i 0x1d4d flash system filename.img' - DO NOT INTERRUPT THIS PROCESS (where filename.img is the image file you extracted from the download zip)
• ON A MAC: enter 'chmod +x adb-mac' followed by 'chmod +x fastboot-mac' followed by './adb-mac reboot bootloader', when the device has rebooted to bootloader enter './fastboot-mac -i 0x1d4d flash system filename.img' - DO NOT INTERRUPT THIS PROCESS (where filename.img is the image file you extracted from the download zip)
• ON A LINUX PC: enter 'chmod +x adb-linux' followed by 'chmod +x fastboot-linux' followed by './adb-linux reboot bootloader', when the device has rebooted to bootloader enter './fastboot-linux -i 0x1d4d flash system filename.img' - DO NOT INTERRUPT THIS PROCESS (where filename.img is the image file you extracted from the download zip)
• Use the volume buttons to select 'REBOOT' on the device and choose the option with the power button
• Enjoy your rooted device!

Support

If you need support for this root, please post in this topic. Or just post to say thanks! :)

If you'd like to donate to say thank you, you can do so on my charitable giving page or by signing up to a MoDaCo subscription.

[Guest thefunkygibbon]

excellent. many many thanks Paul.  will try this shortly.

a couple of questions if you will.

a) will it wipe device?

B) I'm assuming that until someone creates a recovery for the device it means we're stuck using this rom ... forever?  assuming that tesco updates will not work or if they do will kill the root.

Edited October 16, 2014 by thefunkygibbon

[Guest Catastrophe]

Wait! This is not how to root it, its just re-flashing the system with root binaries. How did you manage to get 'root' into the system in first place in order to extract the image from device?

Edited October 16, 2014 by Catastrophe

[Guest Hukfed]

Not working.... It gives this error.......   " target reported max download size of 1260890794 bytes error: cannot load 'system.hudl2.rooted.20140924.194555.ONLY.img' "

Edited October 16, 2014 by Hukfed

[Guest iain26]

downloaded and flashed fine but it fails when trying to update the su bins

[Guest iain26]

working fine tho apart from the message say bins need updated

[Guest Simon O]

Not working.... It gives this error.......   " target reported max download size of 1260890794 bytes error: cannot load 'system.hudl2.rooted.20140924.194555.ONLY.img' "

 

Did you check that your Hudl2 is running the correct rom version?

[Guest vermillions]

Thank you for the rooted system img. If possible could you please explain how you achieved root in the first place as I would like to learn and try this regardless of the dangers, as learning is everything.

Thanks again for all your hard work.

[Guest Hukfed]

Did you check that your Hudl2 is running the correct rom version?

Yes, but just to confirm.... Build number, KOT49H.rel.android-build.20140924.194555 release-keys

[Guest PaulOBrien]

a ) will it wipe device?

b ) I'm assuming that until someone creates a recovery for the device it means we're stuck using this rom ... forever?  assuming that tesco updates will not work or if they do will kill the root.

a ) no

b ) OTAs should work fine, but we'll cross that bridge when we come to it! 

 

Not working.... It gives this error.......   " target reported max download size of 1260890794 bytes error: cannot load 'system.hudl2.rooted.20140924.194555.ONLY.img' "

The file isn't in the directory you are in!

 

downloaded and flashed fine but it fails when trying to update the su bins

 

working fine tho apart from the message say bins need updated

Checking that now, probably a permissions thing! :)

P

[Guest iain26]

tried to edit the build prop to change the dpi and it wont save so there does seem to be a problem with permissions 

[Guest Hukfed]

a ) no

b ) OTAs should work fine, but we'll cross that bridge when we come to it! 

 

The file isn't in the directory you are in!

 

 

Checking that now, probably a permissions thing! :)

P

 

Yeh, it most definately is....

[Guest vermillions]

I also have the su binary needs updating. 

[Guest PaulOBrien]

Yeh, it most definately is....Untitled.jpg

Try losing the space in the directory name perhaps?

P

[Guest PaulOBrien]

A few teething troubles folks but we'll work through them.

Root DOES still work however, albeit with that SuperSU nag. :)

P

[Guest Hukfed]

Try losing the space in the directory name perhaps?

P

Nope exactly the same error........

Edited October 16, 2014 by Hukfed

[Guest iain26]

try renaming the file to something shorter, like hudl.img, easier to type without making mistakes

[Guest PaulOBrien]

Nope exactly the same error........

Hmm, well the command line suggests it can't see the image! Try running the command prompt as administrator?

P

[Guest PaulOBrien]

I have updated the system image in the first post to resolve the perpetual-updating-SuperSU issue (just repeat the process).

It appears that even when rooted /system write access is protected, which is a pain, hence why it wasn't auto-fixing. :(

P

[Guest vermillions]

Root explorer will not let me mount as read and write in any dir but superuser has given access to root. Also Titanium backup is unable to uninstall apps, it says it has but they are not fully uninstalled and are fully working on reboot.So I think it maybe a more serious problem than just the Su update nag.

 

Sorry i should have refreshed screen before posting as it seems you have fixed it.

Edited October 16, 2014 by vermillions

[Guest PaulOBrien]

Looks like a lock preventing /system change, use Titanium to Freeze rather than uninstall for apps you want to be rid of!

P

[Guest geegeethatsme]

How about using something like SUFBS to get read/write permissions in /system/app and just delete the unwanted apk file?  Apologies if that's not the right folder structure.  Haven't got my hands on a H2 yet.

[Guest Hukfed]

Hmm, well the command line suggests it can't see the image! Try running the command prompt as administrator?

P

No still the same error.... I've tried all suggestions given here..... Checked and double checked files are all in the same folder, shortend .img name, run CMD in admin mode, re-tried with r2.img..... Would a Data/Factory reset solve my problem does anyone think ?

[Guest PaulOBrien]

No still the same error.... I've tried all suggestions given here..... Checked and double checked files are all in the same folder, shortend .img name, run CMD in admin mode, re-tried with r2.img..... Would a Data/Factory reset solve my problem does anyone think ?

No, definitely not, it's an issue on the PC...

P

[Guest mbalax]

mm getting the same or similar error:

 

target reported max download size of 1260415658 bytes
sending 'system' (1160176 KB)...
FAILED (command write failed (Invalid argument))
finished. total time: 0.002s