flashing kernels help

**Edwill86** · 11-14-2012, 09:05 AM

ok so I got my self into a bind. its my first ever boot loop!

ok so I have 4.2 flashed. i am running stock rom and recovery. I rooted.

now in my stupidity early this morning I decided to use francos kernel updater to flash a kernel.. forgot that 4.2 just came out for the nexus 7.. so it just sitts trying to boot and never does. obviously because the kernel isn't compatible with 4.2.

now I have the stock kernel backed up with the franco updater app. doesn't help because I cant boot.

I could use wugs tools to flash back to stock 4.1.2.. but I really want that to be a last resort. I had to flash stock last night to get to 4.2 it was a pita.

so I have used wugs to temp boot into twrp. i can see the back up. "factory.img" so how do I get it to flash the img back to factory?

:/

**2defmouze** · 11-14-2012, 11:55 AM

Download the factory image from Google, unzip it, locate the boot.img file. This is the kernel. Fastboot it using:
fastboot flash boot boot.img
Or have the toolkit flash it as a kernel, if that's an option. I obviously recommend fastbooting it on your own

Sent from my Galaxy Nexus using Tapatalk 2

**Edwill86** · 11-14-2012, 01:12 PM

Originally Posted by 2defmouze

Download the factory image from Google, unzip it, locate the boot.img file. This is the kernel. Fastboot it using:
fastboot flash boot boot.img
Or have the toolkit flash it as a kernel, if that's an option. I obviously recommend fastbooting it on your own

Sent from my Galaxy Nexus using Tapatalk 2

Can u link me to the stock kernel and a walk through on how to use fast boot to flash it? I'm at work for a while.thanks

**Edwill86** · 11-14-2012, 02:02 PM

Originally Posted by Edwill86

Can u link me to the stock kernel and a walk through on how to use fast boot to flash it? I'm at work for a while.thanks

I have the 4.2 zip from google already duh! Just need a walk through flashing it with fast boot.

**2defmouze** · 11-14-2012, 03:49 PM

Originally Posted by Dieter Bohn

Phew! It took some doing, but I've put up my review of Android.

I feel like I barely scratched the surface, though, please ask questions if you have them!

Review: Android on the T-Mobile G1 | Android Central

Check my factory restore guide, or the other guides for the files, etc. Then you literally just boot to the bootloader and enter the command I gave you above, after you place the boot.img file from the factory image in your fastboot directory and open a command window there

Sent from my Galaxy Nexus using Tapatalk 2

**Edwill86** · 11-14-2012, 03:56 PM

yeah I found it that 5 mins ago :P I just followed It and used your fastboot boot boot.img command and wallah its booting back up as I type!

and............................... DONE! prefect thanks man! I dont have to restore my tablet at all!!!!!!!!!!!!!

**2defmouze** · 11-14-2012, 04:10 PM

Originally Posted by Edwill86

yeah I found it that 5 mins ago :P I just followed It and used your fastboot boot boot.img command and wallah its booting back up as I type!

and............................... DONE! prefect thanks man! I dont have to restore my tablet at all!!!!!!!!!!!!!

Atta boy... And now you learned something. It all comes full circle

Sent from my Galaxy Nexus using Tapatalk 2

**Edwill86** · 11-16-2012, 06:04 PM

Maybe I'll try and flash a rom to my vzw gnex now that I have finally had my first boot loop and fixed it.

**balboa 147** · 11-24-2012, 12:48 AM

Originally Posted by 2defmouze

Check my factory restore guide, or the other guides for the files, etc. Then you literally just boot to the bootloader and enter the command I gave you above, after you place the boot.img file from the factory image in your fastboot directory and open a command window there

Sent from my Galaxy Nexus using Tapatalk 2

I have the same problem. I flashed the .img (bootloader-grouper-4.13) file from the google zip (nakasi-jop40c-factory-6aabb391) using Google Nexus 7 Toolkit by mskip in fastboot mode. Flash successful but 'Booting failed' appeared in white at the top left of the screen!

Help, please!

I'd like to revert back to my stock rom but I would like to avoid data wiping if possible.

**2defmouze** · 11-24-2012, 11:11 AM

Originally Posted by balboa 147

I have the same problem. I flashed the .img (bootloader-grouper-4.13) file from the google zip (nakasi-jop40c-factory-6aabb391) using Google Nexus 7 Toolkit by mskip in fastboot mode. Flash successful but 'Booting failed' appeared in white at the top left of the screen!

Help, please!

I'd like to revert back to my stock rom but I would like to avoid data wiping if possible.

If your problem is the kernel, you just flashed the wrong thing, lol. The bootloader is unrelated.. Flashing the boot.img (the kernel) with "fastboot flash boot boot.img" is what you wanted, the bootloader is a different thing altogether.

**balboa 147** · 11-24-2012, 11:33 AM

Originally Posted by 2defmouze

If your problem is the kernel, you just flashed the wrong thing, lol. The bootloader is unrelated.. Flashing the boot.img (the kernel) with "fastboot flash boot boot.img" is what you wanted, the bootloader is a different thing altogether.

Can you give me a tutorial on how to do this, please? Is the boot img (bootloader-grouper-4.13) the correct file to flash?

I did not do a back up of my apps' data, and i can only do it in after completey booting, so is reverting back to the stock rom possible without wiping data?

**2defmouze** · 11-24-2012, 12:23 PM

Originally Posted by balboa 147

Can you give me a tutorial on how to do this, please? Is the boot img (bootloader-grouper-4.13) the correct file to flash?

I did not do a back up of my apps' data, and i can only do it in after completey booting, so is reverting back to the stock rom possible without wiping data?

The file "bootloader-grouper-4.13.img" is the bootloader.... the file "boot.img" is the kernel, they are 2 completely different files. You want to just fastboot flash the kernel. Not much to walkthrough, if you can boot to the bootloader you just flash it using "fastboot flash boot boot.img"... making sure you have found the boot.img file (it is inside the .zip containing the system, which is inside the factory image download) and copied it to your directory where your adb and fastboot files are.

If you can get that flashed and it allows you to boot up it won't wipe anything, and that would be a great time to backup everything of course

**balboa 147** · 11-24-2012, 12:46 PM

Originally Posted by 2defmouze

The file "bootloader-grouper-4.13.img" is the bootloader.... the file "boot.img" is the kernel, they are 2 completely different files. You want to just fastboot flash the kernel. Not much to walkthrough, if you can boot to the bootloader you just flash it using "fastboot flash boot boot.img"... making sure you have found the boot.img file (it is inside the .zip containing the system, which is inside the factory image download) and copied it to your directory where your adb and fastboot files are.

If you can get that flashed and it allows you to boot up it won't wipe anything, and that would be a great time to backup everything of course

Omg thank you thank you thank you so much!!!

I was scouring the internetz for boot.img, and being such a noob, i thought the img's name is supposed to be "fastboot flash boot boot.img"! I never thought to check within the zip that contains the system!

Franco of franco.kernel should have put in a warning for 4.2 users that says his kernel is incompatible with 4.2. If he did, i must have missed it.

Time to back up everything, and then it's time I really use the nexus7 like it's meant to be used, with ROMs and custom kernels!

Again, thank you so, so much, 2defmouze, you're a legend