cfdisk created GPT tables are not recognized by the Windows 8.1 installer

cfdisk created GPT tables are not recognized by the Windows 8.1 installer

[Kay Sievers]

Hey,

the Windows 8.1 installer does not recognize the GPT partition tables
created with cfdisk. It claims it will need to initialize the entire
disk to install Windows.

Reading-in the cfdisk-created table and writing-back the very same
table with parted, makes the Windows installer recognizes it, and
Windows just its two additional partitions.

I've installed Windows on that box now and don't want to try this
again, but maybe looking at the difference what parted will change in
the cfdisk created table is sufficient to find the bug.

Thanks,
Kay

Re: cfdisk created GPT tables are not recognized by the Windows 8.1 installer

[Karel Zak]

On Thu, Dec 25, 2014 at 11:57:56PM +0100, Kay Sievers wrote:
> the Windows 8.1 installer does not recognize the GPT partition tables
> created with cfdisk. It claims it will need to initialize the entire
> disk to install Windows.

hmm... the difference which I see is that libparted uses HeaderSize=92
and libfdisk HeaderSize=512. In libfdisk we count reserved area at the 
end of the first sector to header. The both solutions are pretty
valid according to standard, but I guess that Windows installer does
not real all the sector so crazy things may happen (crc, ...).

> Reading-in the cfdisk-created table and writing-back the very same
> table with parted, makes the Windows installer recognizes it, and
> Windows just its two additional partitions.
> 
> I've installed Windows on that box now and don't want to try this
> again

Sure, Christmas time with Windows 8... seems like Santa Claus hates
you; be better this year :-))

> but maybe looking at the difference what parted will change in
> the cfdisk created table is sufficient to find the bug.

Yep, thanks!

    Karel
-- 
 Karel Zak  <kzak@redhat.com>
 http://karelzak.blogspot.com