[K3] Custom Kernel (rescue shell !, kexec, patched recovery)

[seaniko7]

Hello again.

Here's my custom kernel for Kindle 3 with some nice features :

- Rescue shell access over USB-Serial
- Kexec support
- Patched Recovery Mode

1. Rescue shell Boot procedure :
- After kernel is loaded by bootloader it creates required nodes and loads g_serial module for serial-over-usb mode.
- It waits 70s for connection with host machine

Connection parameters :

Spoiler:

ttyACM0, 115200 8N1

If user connected to Kindle terminal ( let's say via minicom )

Spoiler:

It asks for login and password, which is :

login : root
password : fiona

If no connection is found, Kindle boots as usual.

1.1 Additional scripts :
start-os - starts Kindle OS

2. Recovery mode Boot procedure :
- Reboot Kindle holding power switch for 20s, and then hold enter key on keyboard for 80s
- From Recovey mode press ALT+E to export mmcblk0p1 over USB

3. Kexec kernel execution :
- run "kexec -l <path to your uImage>"
- run "kexec -e"

v0.1

Spoiler:

http://dl.dropbox.com/u/16679763/kin...ell_kernel.zip

Enjoy.

PS: In not-so-far future I'll prepare similiar kernels for KT & KNT with shell over usbNetwork and scp support.

[geekmaster]

Awesome!

[inameiname]

What is the advantage of having this over, say, the default kernel, with the USBNetwork hack and/or terminal emulator program installed?

Sorry to sound so ignorant, I just am curious what the benefits are. Does the custom kernel make the whole firmware and OS run better/faster? Again, for us less-kernel-knowledged people. Hehe.

Also, is it possible to get an uninstall.bin for this hack? I always like the ability to easily uninstall all that I install.

Thanks in advance.

[giorgio130]

[root@kindle us]# kexec -l main_kernel.img
Cannot open /proc/atags: No such file or directory
kexec_load failed: Function not implemented
entry = 0x80008000 flags = 280000
nr_segments = 2
segment[0].buf = 0x28028
segment[0].bufsz = 10
segment[0].mem = 0x80001000
segment[0].memsz = 1000
segment[1].buf = 0x40154008
segment[1].bufsz = 20f000
segment[1].mem = 0x80008000
segment[1].memsz = 20f000

I get the same error as in the other thread. Did you read my post?

To avoid confusion, I'm on a K3G, maybe you're testing on another platform...

[seaniko7]

Originally Posted by inameiname

What is the advantage of having this over, say, the default kernel, with the USBNetwork hack and/or terminal emulator program installed?

Sorry to sound so ignorant, I just am curious what the benefits are. Does the custom kernel make the whole firmware and OS run better/faster? Again, for us less-kernel-knowledged people. Hehe.

Also, is it possible to get an uninstall.bin for this hack? I always like the ability to easily uninstall all that I install.

Thanks in advance.

Rescue shell gives you possibility to :

- fix changes that caused so called "brick"
- boot another OS, for example Debian, Android ( only on KT with usbNetwork via NFS mounted from kernel level )
- create boot-menu for above by loading eink modules ( atm I have no idea how to achieve this ... )

I don't have original 3.3 kernel for uninstaller. I'd be very thankful if someone could extract it using geekmaster awesome getkernels tool.

@giorgio130, I've flashed two K3W without issues. If update doesn't work, you can also flash it manually using Amazon tools.

- Download uImage from here : http://dl.dropbox.com/u/16679763/uImage
- Copy it to /mnt/us
- Execute :

cp /mnt/us/uImage /tmp ; /test/flashtools/luigi/update /tmp/uImage

[giorgio130]

Thanks, it worked this time! Is it possible that the update package for k3g contains a stock kernel?

[geekmaster]

Originally Posted by seaniko7

I don't have original 3.3 kernel for uninstaller. I'd be very thankful if someone could extract it using geekmaster awesome getkernels tool.

Done! Download URL is at the bottom of this list: http://pastebin.com/Wdw4L7yT

EDIT: This compressed very little with gzip. Is it a compressed kernel?

[thomass]

Originally Posted by geekmaster

...http://pastebin.com/Wdw4L7yT...

to have a better url I shorten(?) it: tinyurl.com/kindleimages

well, if you don't trust me then use this one: preview.tinyurl.com/kindleimages

[geekmaster]

Originally Posted by thomass

to have a better url I shorten(?) it: tinyurl.com/kindleimages

well, if you don't trust me then use this one: preview.tinyurl.com/kindleimages

We are removing direct links due to warnings on the parent Amazon Kindle forum. Links to lists of links are MUCH less likely to be a problem.

[inameiname]

Originally Posted by seaniko7

Rescue shell gives you possibility to :

- fix changes that caused so called "brick"
- boot another OS, for example Debian, Android ( only on KT with usbNetwork via NFS mounted from kernel level )
- create boot-menu for above by loading eink modules ( atm I have no idea how to achieve this ... )

I don't have original 3.3 kernel for uninstaller. I'd be very thankful if someone could extract it using geekmaster awesome getkernels tool.

@giorgio130, I've flashed two K3W without issues. If update doesn't work, you can also flash it manually using Amazon tools.

- Download uImage from here : http://dl.dropbox.com/u/16679763/uImage
- Copy it to /mnt/us
- Execute :

cp /mnt/us/uImage /tmp ; /test/flashtools/luigi/update /tmp/uImage

Thanks for the info. I love the idea of being able to boot Debian or Android, however, it is a shame that is for the Kindle Touch, and not also for Kindle 3. Will it ever be possible to get that working for the Kindle 3?

Now, would having a K3G versus K3W (which you used) matter in terms of using this custom kernel?

[twobob]

Originally Posted by seaniko7

Rescue shell gives you possibility to :

- fix changes that caused so called "brick"
- boot another OS, for example Debian, Android ( only on KT with usbNetwork via NFS mounted from kernel level )
- create boot-menu for above by loading eink modules ( atm I have no idea how to achieve this ... )

I don't have original 3.3 kernel for uninstaller. I'd be very thankful if someone could extract it using geekmaster awesome getkernels tool.

@giorgio130, I've flashed two K3W without issues. If update doesn't work, you can also flash it manually using Amazon tools.

- Download uImage from here : http://dl.dropbox.com/u/16679763/uImage
- Copy it to /mnt/us
- Execute :

cp /mnt/us/uImage /tmp ; /test/flashtools/luigi/update /tmp/uImage

Thanks very much for your work on this

[trex_daemon]

Hello,
I've flashed the custom kernel, and also connected a serial console to it.
When it says Welcom to our world, I'm trying to connect to the tttACM0 115200 8 1 , the login screen shows , but after a while it automatically gets filled in with AT+GCAP. I'm using putty or screen, happens with both. Any idea why ?

[trex_daemon]

I've managed to find the root cause of the AT commands.
See explanation here.
http://ubuntuforums.org/showthread.php?t=2056285

[Yasen6275]

How hard will be to redo that for 3.4 versdon of software?

[knc1]

Originally Posted by Yasen6275

How hard will be to redo that for 3.4 versdon of software?

The 3.3 and 3.4 firmware use the same kernel.
Keep in mind that the kernel modules are part of the system image.