how to flash modified boot.img ?

[professor_jonny]

so i have modified my boot.img verified it boots from external sd now how do i flash it to the file to the tablet ?

i have tried fastboot to boot into bootloader mode but it does not work.

I believe I can't push it from recovery as it would need to be signed with keys and scripted, and all the tools on google play either you have to pay or require android versions above my tablet.

also the new boot image is smaller do i have to pad and align it or will it work as it is ?

[shaunmt]

so i have modified my boot.img verified it boots from external sd now how do i flash it to the file to the tablet ?

i have tried fastboot to boot into bootloader mode but it does not work.

I believe I can't push it from recovery as it would need to be signed with keys and scripted, and all the tools on google play either you have to pay or require android versions above my tablet.

also the new boot image is smaller do i have to pad and align it or will it work as it is ?

It would really help if you would advise everyone which device you have... I don't remember which one you have...

Do you have a custom recovery like CWM or TWRP for your device? You can attempt to flash any update package with CWM or TWRP. Doesn't have to be signed all, CWM and TWRP don't even check signatures, unless you turn on signature verification in the settings.

Are you sure your new boot image is good? When you attempt to boot from SD card, if the image on the SD card fails, the device will automatically revert to the internal image. Did you verify that it booted the new image and not the internal image?

The new ramdisk has to be the same size as the old ramdisk. I use CXZ's scripts from slatedroid, which automatically check the size, warn you if it is too big, and pad it if it smaller.

ShaunMT

[professor_jonny]

I have a next712mc model.

Im 100% sure it booted from the modified one as all my patches showed up when i booted, I used CZX's unpack/repack script and it booted fine from sd card, but it may not from flash as from what you say it will need padding aligning and packing into an update zip to flash.

This is the process I dont know how to do correctly.

my original boot image is 8mb and the repacked one is 3.5mb i dont know if i flash this the system will still boot up.

I do have an alternative recovery you got me to test one of your TWRP images on my tablet the other day,which works perfect.

[shaunmt]

I have a next712mc model.

Im 100% sure it booted from the modified one as all my patches showed up when i booted, I used CZX's unpack/repack script and it booted fine from sd card, but it may not from flash as from what you say it will need padding aligning and packing into an update zip to flash.

This is the process I dont know how to do correctly.

my original boot image is 8mb and the repacked one is 3.5mb i dont know if i flash this the system will still boot up.

I do have an alternative recovery you got me to test one of your TWRP images on my tablet the other day,which works perfect.

Thanks for reminding me which model you are working on and confirming that you are sure your modified boot image works.

The ramdisk is the only part that has to be the correct size and the CZX's script took care of that part.

The image file does not have to be same size and it won't be. The reason it isn't the same size is because when you dumped the stock one, you also got all the blank space at the end of the partition. This won't matter when you flash the new image file.

All you need to do now is create an update.zip to flash your new boot image.

Alternatively, you could probably DD it back also, but I've never actually tried to do it this way, and it's not a very user friendly method if you are planning a public release.

ShaunMT

[professor_jonny]

I gave up on creating an update zip I could not get it to work but I can confirm dd works:

dd if=/data/local/boot.img of=/dev/block/mtdblock4

It is a little bit more risky but it worked :-).