Hi,

It seems that GRUB can't read disk partitions that have been converted into
"Dynamic" or LDM format by Windows. This format is a prerequisite for
software RAID on Windows, so it would definitely be useful to have.
(With modern Windows versions, unlike XP, it all became actually possible.)
But at the same time that would mean sacrificing dual-boot via GRUB, so
instead I am forced to sacrifice RAID1 data protection "over there" in
order to get "over here".

Linux kernel source Documentation/ldm.txt says:

  If you enable LDM support, then lilo is capable of booting from any of the
  discovered partitions.  However, grub does not understand the LDM partitioning
  and cannot boot from a Dynamic Disk.

I skimmed the modern GRUB sources and couldn't find much trace of LDM.
Google finds http://grub-ldm.sourceforge.net/, but it's dated 2005 and
the patch is based on the old branch:

% diffstat < grub-ldm.diff
 ChangeLog          |    3
 stage2/Makefile.am |   26 -
 stage2/builtins.c  |    7
 stage2/char_io.c   |    8
 stage2/disk_io.c   |   47 ++
 stage2/ldm.c       | 1079 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 stage2/ldm.h       |  234 +++++++++++
 stage2/list.h      |  154 +++++++
 stage2/pc_slice.h  |    6
 9 files changed, 1543 insertions(+), 21 deletions(-)

I also found the request from 2002 at the bug-grub mailing list
http://www.mail-archive.com/bug-grub@gnu.org/msg05156.html
apparently from the person who first wrote linux/fs/partitions/ldm.[ch]
So I'm just echoing it, eight years later :)

Please implement this. TIA.

Josip Rodin wrote:
I added it to mainstream tasktracker but I doubt anyone will step in
anytime soon. I guess if you want it to be done, you'll have to use one
of proven methods (do it yourself, hire someone to do it or forbid your
children to do it)

FWIW that's at http://savannah.gnu.org/task/?10165