Re: libgparted bug.
- Date: Fri, 9 Feb 2018 18:22:05 -0500
- From: Gene Heskett <gheskett@xxxxxxxxxxx>
- Subject: Re: libgparted bug.
On Friday 09 February 2018 14:37:16 Thomas Schmitt wrote:
> your count=122070 was too small. It should have been 128912. See
> Gene Heskett wrote:
> > gene@coyote:~/rock64.imgs$ /sbin/gdisk -l rock-img-shrunk.img
> > [...]
> > Caution: invalid backup GPT header, but valid main header;
> > regenerating backup header from main header.
> You cut off ~ 56 GB of the original device data. At the very end of
> the original there is the GPT backup copy. So it was not copied.
> > Warning! One or more CRCs don't match. You should repair the disk!
> This is not a good sign. GPT has checksums in the header block. One
> for the header itself and one for the partition entries array.
> If any does not match, then some partition editing did not what it
> was supposed to do.
> Well, old sins ...
> > Total free space is 108670973 sectors (51.8 GiB)
> gdisk seems still to believe in the size which it found in the copied
> GPT header block. Hopefully this misbelief would end if the image was
> copied successfully to a new storage medium.
> Nevertheless, gdisk or an other partition editor will then have to
> adjust this size field in the GPT (and the checksums) to the real
> storage device size.
> > Number Start (sector) End (sector) Size Code Name
> > 1 64 8063 3.9 MiB 8300 loader1
> > 2 8064 8191 64.0 KiB 8300 reserved1
> > 3 8192 16383 4.0 MiB 8300 reserved2
> > 4 16384 24575 4.0 MiB 8300 loader2
> > 5 24576 32767 4.0 MiB 8300 atf
> > 6 32768 262143 112.0 MiB 0700 boot
> > 7 262144 16500735 7.7 GiB 8300 root
> The first six partitions should be like on the original card.
> I am not so sure about number 7.
> Does it have the same size on the original card ?
> If it is like on the original:
> For a good copy up to the end of partition 7 you would have had to
> copy 16500735*512/65336 = 128912 blocks.
> So now your copy lacks the last 6842 * 65336 = 447,028,912 bytes of
> partition 7.
> With a copy of 128912 * 64 KiB the image file should be good and you'd
> only have to solve the riddle why the new card did not take the bytes
> you copied to it (or why it put them at the wrong place).
Blame that on gparted which did not update the ending GPT table when I
shrank part 7 from 59.6 GB to about 7 so it would fit on a smaller sd
seems to have fixed that, gparted is now as happy as a clam.
> Have a nice day :)
Cheers, Gene Heskett
"There are four boxes to be used in defense of liberty:
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