error: Unable to find destination block device: /dev/mmcblk0

[Roberto Innocenti]

I have posted here because until now nor samsung , nor chrome os ninja are able to go deep in this
I hope to find someone that have deep knowledge about Chrome OS ( in particular on Samsung ARM Chromebook) .

I'm a gnu/linux expert and I have buyed from ebay an used Samsung ARM Chromebook ( without the original receipt) with the idea to install on it gnu/linux, but

- my Chromebook remain "verification mode OFF" even if I press SPACE and ENTER to put Verification ON, it tell me Verification OFF,
then it reboot fast and again still appear "verification mode OFF", and every some seconds it beep.

- Pressing ESC+Refresh and Power it go in to Recovery Mode, it tell me "Chrome OS is missing or damaged, Please insert a recovery USB stick or SD card", so i put the USB Stick with the right Recovery image and it start to test the recovery image and and the end stop with an "unexpected error".

- Looking at the file recovery.log generated on the Usb Stick I can see all the process of the chromeos-install script and the when it stop it
+ echo 1
+ local install_status
+ [ -x /usb/usr/sbin/chromeos-recovery ]
+ chroot /usb /usr/sbin/chromeos-recovery /dev/sda
Error: Unable to find destination block device: /dev/mmcblk0

So it doesn't find the SSD (eMCC) on /dev/mmcblk0.

- I have tested that if I make the recovery from SD ( instead the USB Stick) the SD is mapped as /dev/mmcblk0

My Diagnose:
- I believe that eMCC is working so could be that is wrongly mapped on the device tree, could be that is on /dev/mmcblk1...
- Why is wrongly mapped? Could be that my Chromebook have a changed u-boot?
- Pressing Tab I can see the attached info about firmware , in particular look like it load only RO firmware and not RW firmware,
  becouse I can see dev_boot_signed_ony=0 and I don't see kernel_subkey
  >Could you confirm that I have standard working firmware and a standard u-boot?

How to confirm this hypothesis?
- change the chromeos-install script and specify for example /dev/mmcblk1 as eMCC destination of installation
- boot a diagnostics script to test the devices connected and check if eMCC exists and where is mapped
> Do you have something useful to provide me?

Many Thanks in advance for your time spent reading my post.

Roberto Innocenti
http://deliriotecnologico.blogspot.it/

[ggg]

Hi Roberto,

On Sunday, July 21, 2013 4:53:29 AM UTC-7, Roberto Innocenti wrote:

...

- my Chromebook remain "verification mode OFF" even if I press SPACE and ENTER to put Verification ON, it tell me Verification OFF,
then it reboot fast and again still appear "verification mode OFF", and every some seconds it beep.

Verification setting sounds like a separate problem. I'm going to ignore for now since I don't know how to diagnose this.

 

- Pressing ESC+Refresh and Power it go in to Recovery Mode, it tell me "Chrome OS is missing or damaged, Please insert a recovery USB stick or SD card", so i put the USB Stick with the right Recovery image

To confirm "right", can you tell me which (exactly) recovery image you are using?

A specific version from /etc/lsb-release, recovery image file name, or link to the recovery-image is sufficient.

  

and it start to test the recovery image and and the end stop with an "unexpected error".

- Looking at the file recovery.log generated on the Usb Stick I can see all the process of the chromeos-install script and the when it stop it
+ echo 1
+ local install_status
+ [ -x /usb/usr/sbin/chromeos-recovery ]
+ chroot /usb /usr/sbin/chromeos-recovery /dev/sda
Error: Unable to find destination block device: /dev/mmcblk0

That's not good. Can you send me the complete recovery.log please? 

(Offlist - or post someplace public and provide a link)

So it doesn't find the SSD (eMCC) on /dev/mmcblk0.

- I have tested that if I make the recovery from SD ( instead the USB Stick) the SD is mapped as /dev/mmcblk0

My Diagnose:
- I believe that eMCC is working so could be that is wrongly mapped on the device tree, could be that is on /dev/mmcblk1...

Normally, mmcblk1 is the add-on SD card slot, not the build-in eMMC boot device.  I find it hard to believe this is a mapping problem since I've not yet seen a boot log (dmesg output after boot) where the mapping is wrong.

That doesn't mean your machine is behaving correctly. I'd need to see "dmesg" output when booting from any boot device to confirm.

 

- Why is wrongly mapped? Could be that my Chromebook have a changed u-boot?
- Pressing Tab I can see the attached info about firmware , in particular look like it load only RO firmware and not RW firmware,
  becouse I can see dev_boot_signed_ony=0 and I don't see kernel_subkey
  >Could you confirm that I have standard working firmware and a standard u-boot?

You might be able to run "/usr/sbin/chromeos-firmwareupdate --mode autoupdate" to get the RW firmware updated.  This should only help in any case.

How to confirm this hypothesis?
- change the chromeos-install script and specify for example /dev/mmcblk1 as eMCC destination of installation
- boot a diagnostics script to test the devices connected and check if eMCC exists and where is mapped
> Do you have something useful to provide me?

Sorry - I don't have any advice yet. Not until I see the complete recovery.log and dmesg output from boot.

cheers,

grant