PW3 Unbricked PW3 successfully, now I don't have diags

[ForensicKindle]

Howdy,

This starts when I was trying to downgrade my Paperwhite 3 (Non JB- FW 5.8.9.0.1 from factory, upgraded to FW 5.9.2.0.1 via Kindle update) via the serial port.

In this process I erased MMC0 by mistake and naturally ended up with a hard bricked kindle.

In the shining light of this I figured out how to successfully unbrick and downgrade my firmware, and now have a functioning Kindle again at FW 5.8.2.

Now my issue is that I cannot get in to diags, it seems that even though I've successfully flashed the firmware, I think I am missing the DIAGs partition.

Trying to bootm 0xE4100 doesn,t work, giving an error that uboot can't get kernal image, and chucking the ENABLE_DIAGS on the root of the /mnt/us directory and rebooting just boots normally.

I have tried flashing multiple firmware versions, as well as flashing an older firmware, then updating to a newer one, and while they all work, none of them seem to re-write the diag partition.

I'm kind of stuck here, a nod in the right direction would be apreciated

[knc1]

Originally Posted by ForensicKindle

Howdy,

This starts when I was trying to downgrade my Paperwhite 3 (Non JB- FW 5.8.9.0.1 from factory, upgraded to FW 5.9.2.0.1 via Kindle update) via the serial port.

In this process I erased MMC0 by mistake and naturally ended up with a hard bricked kindle.

In the shining light of this I figured out how to successfully unbrick and downgrade my firmware, and now have a functioning Kindle again at FW 5.8.2.

Now my issue is that I cannot get in to diags, it seems that even though I've successfully flashed the firmware, I think I am missing the DIAGs partition.

Trying to bootm 0xE4100 doesn,t work, giving an error that uboot can't get kernal image, and chucking the ENABLE_DIAGS on the root of the /mnt/us directory and rebooting just boots normally.

I have tried flashing multiple firmware versions, as well as flashing an older firmware, then updating to a newer one, and while they all work, none of them seem to re-write the diag partition.

I'm kind of stuck here, a nod in the right direction would be apreciated

https://www.mobileread.com/forums/sh...d.php?t=294485

[bobcat4]

sorry, what is this diags and which step has erased it? I can try to dump my pw3 if it would be helpful.

[knc1]

Originally Posted by bobcat4

sorry, what is this diags and which step has erased it? I can try to dump my pw3 if it would be helpful.

The function: "Erase All" - note, you do not have to try it, it does exactly what it says.

Touchscreen Kindles are all "dual boot" (except KOA2, which is its own type of funky), like having both WinXP and Win10 on the same PC with a choice of which to boot.
In the case of the Kindles, they are called: "main" and "diags" (named for their purpose).

Directions and download here:
https://www.mobileread.com/forums/sh...03#post3569803
The two files needed are:
diag-uImage
diagsys.bin
And none other (some of the others contain personalized information for owner and device and should never become public).

[bobcat4]

Where is this "Erase All"? I ask it because I did downgrade to 5.7.4 initial and sometimes I tried resetting with creating DO_FACTORY_RESTORE file and I would like to know if anything lost on my device in that case.

[knc1]

If you haven't seen it, you don't have to worry about it.
If you do see it, do not be tempted to find out if it really works, it really does.

[ColtB45]

Originally Posted by knc1

https://www.mobileread.com/forums/sh...03#post3569803
The two files needed are:
diag-uImage
diagsys.bin
And none other (some of the others contain personalized information for owner and device and should never become public).

From the statement above would I be correct in understanding that, on a PW3, the diag kernel and diag partition are not unique?

I was under the impression, possibly mistakenly, that the serial was also present in the diag partition. (In addition to it's obvious presence in uBoot)

If so, that's good news because I accidentally killed my wife's diag partition and kernel on her PW3. I could just restore them from my intact PW3.

[knc1]

That is correct.

Just run my back-up script on the good device and among the files it creates will be the two that you need.

serial number and some other things are stored outside of the file systems, which makes them common to both systems.

[ColtB45]

I was able to restore the diag FS with:

dd if=/mnt/us/backup/diagsys.bin of=/dev/mmcblk0p2

But the following doesnt work for the diag kernel.

dd if=/mnt/us/backup/diag-uImage of=/dev/mmcblk0 bs=4096 skip=3649 count=2048

I just get.

0+0 records in
0+0 records out
0 bytes (0B) copied, 0.005913 seconds, 0B/s

I hate to ask for help, but what am I missing? Do I have to revert to fastboot?

Update:
Well I got the diag system restored. Odd thing is the root password computed from that kindles serial doesn't work any more. The password computed from the donor kindles serial does... The only thing changed was the diag kernel and diag FS.

Update 2:
And after a subsequent reboot into the diag system it works with the original password. There's probably a process that sets the shadow file during bootup based on the value of /proc/usid. Either way, you were right and it works.