Grr. Internal partitions locked again...FIXED (for now!)

[offbeatdave]

I'm having the same problem I had described at http://www.jogglerwiki.com/forum/viewto ... ?f=2&t=472 where I cannot get rid of the partitions on the internal flash. Whatever I do (overwrite with zeros, fdisk etc), they come back. In gparted they appear to be deleted but then reappear. This happens whether I reboot or not. Any other suggestions anyone?

[offbeatdave]

Should just clarify that I have tried gparted, fdisk, cfdisk, writing with zeros etc. It appears that I cannot change the partition table which always reverts to:

Code: Select all

Disk /dev/mmcblk0: 1028 MB, 1028128768 bytes
4 heads, 16 sectors/track, 31376 cylinders
Units = cylinders of 64 * 512 = 32768 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

        Device Boot      Start         End      Blocks   Id  System
/dev/mmcblk0p1   *           1        1954       62520   ef  EFI (F
/dev/mmcblk0p2            1955        9768      250048   83  Linux
/dev/mmcblk0p3            9769       17582      250048   83  Linux
/dev/mmcblk0p4           17583       31376      441408   83  Linux

Have also tried the cat part_table thing, with no success. As with the above, it suggests it has worked and written, but then hasn't!

Oh, and have also tried two different efi chips but still no good.

[BuZz]

use dd / hexdump to write over and then read back /dev/mmcblk0 and make sure data is writing correctly.

[offbeatdave]

Hmm. Not sure if I've done this correctly, but here is the result of attempting to write the first 512 with zeros. The hexdump was the same both before and after writing zeros.

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root@joggler:/home/joggler# sudo dd if=/dev/zero of=/dev/mmcblk0 bs=512 count=1
1+0 records in
1+0 records out
512 bytes (512 B) copied, 0.00341121 s, 150 kB/s
root@joggler:/home/joggler# sudo dd if=/dev/mmcblk0 bs=512 count=1 | hexdump -C
1+0 records in
1+0 records out
00000000  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
512 bytes (512 B) copied*
, 0.0015647 s, 327 kB/s
000001b0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 80 01  |................|
000001c0  01 00 ef 03 d0 ff 10 00  00 00 70 e8 01 00 00 03  |..........p.....|
000001d0  d0 ff 83 03 d0 ff 80 e8  01 00 80 a1 07 00 00 03  |................|
000001e0  d0 ff 83 03 d0 ff 00 8a  09 00 80 a1 07 00 00 03  |................|
000001f0  d0 ff 83 03 d0 ff 80 2b  11 00 80 78 0d 00 55 aa  |.......+...x..U.|
00000200

[offbeatdave]

Probably not a reasonable suggestion, but is there any way the internal flash (/dev/mmcblk0) could have become read only and, if so, is there a command to change permissions (like the chmod command for files)?

[BuZz]

It looks that way, but I mean, it cant at the block level afaik unless there is some fault.

running dd as root, there isn't a permissions thing. your dd command looks fine. looks like your flash isn't writable!? or at least not that part. maybe flash can fail in that way. ive always recommended to people to not use the internal flash at all, to avoid wear. maybe another reason - or could be some other hardware fault. I can't think of a software reason for it.

[offbeatdave]

Failed flash, thus rendering it unwritable is what I'm beginning to think. It is on my most temperamental Joggler which has historically been a pain in the proverbial to reflash etc. Looks like it's over the the USB port for an alternative distro on this one...

[offbeatdave]

Is there any way of getting to the Internal Flash via a WinXP distro?

[BuZz]

I don't think there is a trigger like " something failed now it doesnt work". Onboard flash != efi for example. EFI will handle device mapping and hardware so it "may" be possible there is a problem there but you mentioned you tried swapping the efi chip so. It's possible that some parts of the internal flash have failed in a way they are read only. I'm no flash expert too. try writing bytes of FF over the first part and hexdump, or cat some file with some text to dd over the block device and check. maybe some is working and some not. might rule out something.

[offbeatdave]

I'm no flash expert too. try writing bytes of FF over the first part and hexdump, or cat some file with some text to dd over the block device and check. maybe some is working and some not. might rule out something.

When you get a moment, I hope you're expert enough to explain to this simpleton how to so the FF writing as I have already gone well beyond my level of expertise here! Thanks for the suggestions btw. Much appreciated.

[BuZz]

I just meant to write "not zeros" like FF hex/255 decimal to the device.

[offbeatdave]

oh yeah.thanks. will try later.

[offbeatdave]

Back working again!

Not sure what did it.

Had Joggler in bits and decided to boot Ubuntu with efi chip out. Also had wireless dongle out at this point. Then inserted a different (o2 as opposed to Openpeak) EFI chip when booted up and, bizarrely the /dev/mmcblk0 allowed me to make changes once more. I guess this could well all have been co-incidental.

I have subsequently been able to reflash a back-up image from one I previously created.

As someone once said on here,

Tech is weird sometimes.

EDIT: Being unable to resist, I popped everything back together and tried scrubbing flash again. 'Locked' again! It may be a coincidence, but I took it apart again, removed the wireless dongle (and booted from this USB into Ubuntu) and I was able to scrub it again. Left wireless out, ran the reflash tool from birdslikewires. This worked first time. Plugged in wireless when in Stock OS and away I went again. It's all a bit weird, but if it happens again, I shall have the wireless out in the first instance to see what happens.