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[Q][Noobs] I typed command "fastboot erase bootloader"

OP KingMGT

13th March 2014, 08:51 PM   |  #11  
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Quote:
Originally Posted by KingMGT

I very noobs when type command "fastboot erase bootloader". My Nexus 7 is brick.
Can you help me fix this problem?

I am pretty sure your nexus is a paperweight, but can I ask....what possessed you to type that?...
15th March 2014, 04:30 AM   |  #12  
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Quote:
Originally Posted by KingMGT

I very noobs when type command "fastboot erase bootloader". My Nexus 7 is brick.
Can you help me fix this problem?

Curious if you know which bootloader version you have? I'm on 4.23 and I have, out of morbid curiousity, typed that which should never be type... fastboot erase bootloader and it doesn't erase. Says erase failed. Bootloader and Nexus unharmed. That being said, please DO NOT try this at home! But I'm wondering under what circumstances a bootloader would allow itself to be erased? I've flashed bootloaders, which makes total sense, but erasing should never be an option.
15th March 2014, 04:54 AM   |  #13  
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Quote:
Originally Posted by adomol

Curious if you know which bootloader version you have? I'm on 4.23 and I have, out of morbid curiousity, typed that which should never be type... fastboot erase bootloader and it doesn't erase. Says erase failed. Bootloader and Nexus unharmed. That being said, please DO NOT try this at home! But I'm wondering under what circumstances a bootloader would allow itself to be erased? I've flashed bootloaders, which makes total sense, but erasing should never be an option.

You sir, are brave.

Sent from my N5 cell phone telephone....
15th March 2014, 05:06 AM   |  #14  
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Quote:
Originally Posted by adomol

Curious if you know which bootloader version you have? I'm on 4.23 and I have, out of morbid curiousity, typed that which should never be type... fastboot erase bootloader and it doesn't erase. Says erase failed. Bootloader and Nexus unharmed. That being said, please DO NOT try this at home! But I'm wondering under what circumstances a bootloader would allow itself to be erased? I've flashed bootloaders, which makes total sense, but erasing should never be an option.

Hi, adomol...

As politely as I can put this, but "Why?"... did you try this...

Generally, the command...

Code:
fastboot erase <partition_name>
...will delete/erase whatever the named partition occupies. Often, this will be for something relatively innocuous, (eg., fastboot erase boot, fastboot erase userdata, etc.) but it also WILL ERASE THE UNIQUE DEVICE SPECIFIC, CRYPTOSIGNED BOOTLOADER for your unique Nexus 7 if your attempt to erase the bootloader succeeds. And your device is then HARDBRICKED.

---------------------------------------------

I suspect the reason why your quasi-suicidal attempt to brick your Nexus 7 failed, is because your bootloader is probably locked... and fastboot commands fail if the bootloader is locked.

I strongly recommend you desist from further experimentation along these lines.

Rgrds,
Ged.
Last edited by GedBlake; 15th March 2014 at 05:14 AM. Reason: several typos corrected.
15th March 2014, 05:56 AM   |  #15  
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Quote:
Originally Posted by GedBlake

Hi, adomol...

As politely as I can put this, but "Why?"... did you try this...

Generally, the command...

Code:
fastboot erase <partition_name>
...will delete/erase whatever the named partition occupies. Often, this will be for something relatively innocuous, (eg., fastboot erase boot, fastboot erase userdata, etc.) but it also WILL ERASE THE UNIQUE DEVICE SPECIFIC, CRYPTOSIGNED BOOTLOADER for your unique Nexus 7 if your attempt to erase the bootloader succeeds. And your device is then HARDBRICKED.

---------------------------------------------

I suspect the reason why your quasi-suicidal attempt to brick your Nexus 7 failed, is because your bootloader is probably locked... and fastboot commands fail if the bootloader is locked.

I strongly recommend you desist from further experimentation along these lines.

Rgrds,
Ged.

I know it was reckless and could have hardbricked my device, but the thrill overtook me. I have a history of this kind of behavior. But that is beside the point.

I've used fastboot many times and executed most of the usual commands... format, erase, flash, devices, oem unlock, oem lock. All on this very device. The same one I almost euthanized. It is a Nexus 7 2012, unlocked running all-f2fs SlimKat, bootloader version 4.23 (which is the current version.) I flashed that bootloader myself a couple months back when I did a nexus factory image install through fastboot. I also used the erase command on all the usual partitions before flashing them, as I took care of each one seperately.

That being said, I executed the dreaded command on this N7. Result... erase failed

Now that result just brings up more questions, although it would make sense to have fastboot not be able to erase that part or somehow build into the bootloader somekind of failsafe. Could be that 4.23 can't be erased and older versions can?
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15th March 2014, 09:13 AM   |  #16  
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Quote:
Originally Posted by adomol

I know it was reckless and could have hardbricked my device, but the thrill overtook me. I have a history of this kind of behavior. But that is beside the point.

I've used fastboot many times and executed most of the usual commands... format, erase, flash, devices, oem unlock, oem lock. All on this very device. The same one I almost euthanized. It is a Nexus 7 2012, unlocked running all-f2fs SlimKat, bootloader version 4.23 (which is the current version.) I flashed that bootloader myself a couple months back when I did a nexus factory image install through fastboot. I also used the erase command on all the usual partitions before flashing them, as I took care of each one seperately.

That being said, I executed the dreaded command on this N7. Result... erase failed

Now that result just brings up more questions, although it would make sense to have fastboot not be able to erase that part or somehow build into the bootloader somekind of failsafe. Could be that 4.23 can't be erased and older versions can?

Hi, adomol...

You're definitely onto something here... I must be mad, but I've just attempted to erase my bootloader. And encountered a similar error to yours.

So, with every precaution available to hand, here's what I did...

------------------------------------

...made available a known working copy of the v4.23 bootloader.img on my laptop, with the intention of immediately fastboot flashing it, in the event the bootloader erase SUCCEEDED. (Providing you DON'T reboot the device immediately after a bootloader flash failure (or erasure), there is a small window of opportunity to fastboot flash a known working bootloader... before you reboot the device.)

...made available my 'flatline' created 'blob.bin' file, and nvFlash tools...

My device...
Nexus 7 (2012), 16Gb,'grouper' model, WiFi only.
Bootloader v4.23, unlocked.
Custom recovery is TWRP 2.7.0.0
Running rooted KitKat 4.4.2, with modifications (see my sig. for details).

--------------------------------------------------------------------------

With all tools, files and everything I could think of readily available (and my heart in my stomach!!)... I ran the potential Nexus 7 command line killer...

WARNING TO ALL READERS: The following command is potentially VERY dangerous, and may BRICK your device. Do NOT use casually. The previous poster raised an interesting issue regarding the v4.23 bootloader, and what follows is my own risky experiment... which happily, did not brick MY Nexus 7. I can make no such guarantees about YOUR Nexus 7.

Code:
fastboot erase bootloader
It failed... with this error message...

Code:
erasing 'bootloader'...
FAILED <remote: Unsupport Erase bootloader Partition.>
finished. total time: 0.016s
See my attached thumbnail.

So, it DOES appear that, at least as far as the v4.23 bootloader is concerned... it's impossible to deliberately erase it... although accidentally overwriting it, I suspect might be a different matter - eg., inadvertently fastboot flashing a boot.img to the bootloader partition, for example.

Anyway... very nice find, @adomol... you've discovered something interesting as a result of your bravery or foolhardiness... and I can't decide which! Whichever quality it is, I think I share it.

--------------------------------------------------------------------------

Right... I'm off for a cigar, and a drop of whisky to calm my nerves.

Rgrds,
Ged.
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Last edited by GedBlake; 15th March 2014 at 03:11 PM. Reason: Added warning, and corrected several typos.
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16th March 2014, 12:39 AM   |  #17  
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Quote:
Originally Posted by GedBlake


Anyway... very nice find, @adomol... you've discovered something interesting as a result of your bravery or foolhardiness... and I can't decide which! Whichever quality it is, I think I share it.

--------------------------------------------------------------------------

Right... I'm off for a cigar, and a drop of whisky to calm my nerves.

Rgrds,
Ged.

I'm breeding an XDA loony bin in here! It's like Jackass Nexus 7 edition.

Thanks for posting the screenshot, though. I wish I would have been resourceful enough to do that, considering how unlikey these results were thought to have been. Good job @GedBlake!
17th March 2014, 12:21 AM   |  #18  
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@adomol That being the one command that will irrevocably brick a nexus you at either very brave or stupid to type that please tell me you had a blob.bin backup before trying that. Anyway that's an interesting find nonetheless.

Programming is a race between engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning.

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