I have some questions about K4 touch debricking

[drjonvargas]

hi, I just have some facts about the kindle touch that i want to know:
1) Is it possible to brick it via the jailbreak and the screensaver mod made by yifanlu?
2) If i bricked it (badly) is it true that i need to physically open the device and mess up with the internal components? Is there a way to debrick it via software or terminal if that's the case?
3) If i jailbreak my kindle and i want to update it, do i need to remove the mods first and then the jailbreak? and after the update do the same jailbreak work for the new version?
4) Can someone post a simple and effective kindle touch debricking guide (with images) for mac?
5) Is it true that in some cases the brick cannot be repaired?
6) why amazon does not let us use our custom screensavers? (what's wrong with them i find most of the preinstalled screensavers perturbing)
sorry about all of these questions and my bad english grammar, I just hope that I am not disturbing you, but i am truly worried because i do not know if it is a good idea to jailbreak it.
thanks for everything and please help =D

[geekmaster]

You questions are all answered in these (and other) threads and wikis:

Fastboot Manifesto
Select Boot for K4 and Touch
simple kindle touch (and k4nt) debricking method
Kindle4NTHacking wiki
Kindle Touch Hacking wiki

Click the above links and read them.

For specific case details (including using fastboot for Mac), click the "Success Report" links in the simple debricking first post, and read the posts leading up to each success report. For more specific information, learn how to use the mobileread search tools.

AFTER reading the above threads and wikis, then you may ask any remaining questions (in a debricking thread, not a new thread like this).

You MUST invest the time, or you will not understand us when we try to help you. If you cannot invest the time, then invest the money to buy a new kindle and donate the bricked one to somebody who IS willing to invest the time to learn how to debrick it. If you do not want to invest the time or money, then install ONLY amazon approved software on your kindle, or hire somebody to put the unauthorized hacks and mods on it for you.

[drjonvargas]

hey geekmaster, i have seen the links and I have another question.
If I make a dmg image with disk utility of my kindle touch and I brick it, can it restore completely my kindle when I write that dmg on the device?
I think it can be useful because I would be making a dmg of all the device and not a dmg of some partition

[knc1]

Originally Posted by drjonvargas

hey geekmaster, i have seen the links and I have another question.
If I make a dmg image with disk utility of my kindle touch and I brick it, can it restore completely my kindle when I write that dmg on the device?
I think it can be useful because I would be making a dmg of all the device and not a dmg of some partition

I do not think there is a way for you to access the true root of the filesystem with only the Amazon Stock software installed.

The threads you read here about reading/writing the system sections of the filesystem are using either one of the maintenace tools or one of the "hacks" that give access to the root of the filesystem.

So I don't think you will be able to (directly) make a dmg of the Kindle's filesystem.
But you can make copies of it, details are in the threads listed by GM.

[geekmaster]

knc1 is correct.

Some areas of /dev/mmcblk0 are WRITE-ONLY (to protect sensitive information) and you can only request information for these areas from a device driver (/proc interface). So even if you copy the entire mmc image from root (which includes the USB drive contents), there are parts of it that will show as all zero, and writing those back to the mmc can damage the data that is hidden in those locations.

You need kernel mode access to read the protected areas.

EDIT: Now that we have kexec that can run a custom linux kernel loaded from the USB drive, you could modify the linux kernel gpl source code (available from amazon) to give you direct access to the hidden mmc contents, potentially allowing you do make an exact image of the entire mmc device, as you suggested.