Grub2 not recognise GPT when presence hybrid MBR

Hello
Do you still have this issue with a fresh 12.04.1 liveCD ?

if yes, please indicate your Boot-Info URL ( https://help.ubuntu.com/community/Boot-Info )

Hello, YannUbuntu.

Yes. I still have this problem.

Here is link for my boot-info:
http://paste.ubuntu.com/1207043/

Let me ephesize my statement:
If protective GPT record become first - then problem does not appears. It
appears only if it is NOT first.
Reason why I placed it NOT first - becouse my bios (which support UEFI)
refuse to run MBR boot in case it detect protective GPT record.

I have disabled UEFI in bios and using old fashion MBR boot.
I have performed dist-upgrade so here are updated info:

root@helena:~# apt-cache policy grub-pc
grub-pc:
  Installed: 1.99-21ubuntu3.1
  Candidate: 1.99-21ubuntu3.1
  Version table:
 *** 1.99-21ubuntu3.1 0
        500 http://ua.archive.ubuntu.com/ubuntu/ precise-updates/main amd64
Packages
        100 /var/lib/dpkg/status
     1.99-21ubuntu3 0
        500 http://ua.archive.ubuntu.com/ubuntu/ precise/main amd64 Packages

And here are info on version of GRUB
root@helena:~# dlocate -l grub
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Installed/Config-files/Unpacked/Failed-config/Half-installed
|/ Err?=(none)/Hold/Reinst-required/X=both-problems (Status,Err:
uppercase=bad)
||/ Name Version Description
+++-=============================-=============================-============================================================================
un grub <none> (no
description available)
ii grub-common 1.99-21ubuntu3 GRand
Unified Bootloader (common files)
un grub-coreboot <none> (no
description available)
un grub-doc <none> (no
description available)
un grub-efi <none> (no
description available)
rc grub-efi-amd64 1.99-12ubuntu5 GRand
Unified Bootloader, version 2 (EFI-AMD64 version)
ii grub-efi-amd64-bin 1.99-21ubuntu3 GRand
Unified Bootloader, version 2 (EFI-AMD64 binaries)
un grub-efi-ia32 <none> (no
description available)
un grub-emu <none> (no
description available)
ii grub-gfxpayload-lists 0.6 GRUB
gfxpayload blacklist
un grub-ieee1275 <none> (no
description available)
un grub-legacy <none> (no
description available)
un grub-legacy-doc <none> (no
description available)
un grub-linuxbios <none> (no
description available)
ii grub-pc 1.99-21ubuntu3 GRand
Unified Bootloader, version 2 (PC/BIOS version)
ii grub-pc-bin 1.99-21ubuntu3 GRand
Unified Bootloader, version 2 (PC/BIOS binaries)
un grub-yeeloong <none> (no
description available)
un grub2 <none> (no
description available)
ii grub2-common 1.99-21ubuntu3 GRand
Unifi...

/bootmgr and /boot/bcd are present in sda1, so Windows is installed in Legacy mode (although the disk is GPT). The problem is that Ubuntu was installed in EFI mode, when it should have been installed in Legacy mode.
This may be a duplicate of Bug #1050940 .

1) When you installed Ubuntu, which choice did you choose at this screen? ( http://pix.toile-libre.org/upload/original/1312973605.png )

2) Please could you boot your installed Ubuntu, login to your Launchpad account, then type the following command in a terminal:
apport-collect -p ubiquity 998097
This will collect and add information to this report.

apport information

apport information

apport information

apport information

Thanks.
Do you remember which choice you chose at this screen ( http://pix.toile-libre.org/upload/original/1312973605.png ) when you installed Ubuntu ?

>> Do you remember which choice you chose at this screen ( http://pix.toile-libre.org/upload/original/1312973605.png ) when you installed Ubuntu ?

I have performed manual partition of disk.

I do NOT tring to create dualboot - so it is not like Bug #1050940 .
The only I want is to load Ubuntu on GPT partition in legacy mode.
I have set of problems with it which I identify as limitations (bugs?) in GRUB2 and kernel:
1. ( in grub-install) Grub2 refuse to "grub-install /dev/sda" if protective GPT entry is NOT the first.
This bug could be workarounded with method described in bug 2.

2. ( in grub booting - core.img? )I could do grub-install IF protective GPT entry is the first, and to rearainge order of records in MBR so it become not first - but in this case GRUB failed to detect GPT during booting.
During boot shown:
error: no such partition
grub rescue> ls
(hd0)

3. ( in grub-install) IF I do protective record start from sector 2048 - then I could install GRUB in "biosdisk" (?) mode but in this case it installed it data (102 sectors) starting from sector 1 and so corrupt GPT header. I assume that is stage1.5/core.img data ?

4. ( in kernel?) with setup when GPT protective record is NOT first and starts from sector 2048 kernel not able recognise hybrid partition table. in dmesg I see:
[sda]: unknown partition table
same time gdisk sees correct GPT and hybrid MBR

Most correct approach - will be to resolve bug 2. But guess that reqires re-working ASM code.

For now I am trying diferent approach - boot core.img in biosdisk mode and then load correct module (part_gpt) through (hd0,msdos2) and then perform father actions through (hd0,gptN).
For that I need to find way to force GRUB install it stage1.5 not to sector 1 (resolve bug 3) .
I guess for that needed to tweak (or hack) boot.img to point it to new place of core.img

I could easily migrate stage1.5/core.img to diferent place with "dd" - but I do not know how point that place for stage1/boot.img

I see that size of stage1.5 is 51kB(102 sectors) so if I place it starting from sector 1901 it will be good enough. Another option is to use partition gpt12 (EF02) but then either grub must recognise GPT partition table (see bug 2) or point for stage 1 it location in biosdisk mode.

"I have performed manual partition of disk." --> ok. So it's definitely not Bug #1050940 .

"The only I want is to load Ubuntu on GPT partition in legacy mode." --> for this, you need a BIOS-Boot partition. If you haven't, grub-install will return the error you observed in your bug description.

>> for this, you need a BIOS-Boot partition.

I have it all the time.
See partition gpt12 - it has code EF02 so is BIOS-Boot partition.

ok thanks.
Last idea: placing your boot files at the start of the disk (in case you were affected by Bug #1030887 ):
1) via Windows tools, reduce Windows partition from 51.7GB to 50GB, in order to create 2GB free space between sda2 and sda3.
2) in this free space, create a 1GB EXT4 partition , and a new BIOS-Boot partition. (you can delete the old one)
3) Make your Ubuntu use the 1GB EXT4 partition as separate /boot (see https://help.ubuntu.com/community/BootPartition )
4) Please reboot and indicate if you can reproduce the bug.

You can install GRUB 1.98 and apply a patch, if the problem still exists.

http://alpha.gnu.org/gnu/grub/grub-1.98.tar.gz
http://savannah.gnu.org/bugs/?28149
http://savannah.gnu.org/file/grub2-hybrid-mbr-gpt-detect.patch?file_id=19183

Also, if you have an encrypted root, and GRUB 1.98 does not recognize it, remove the following lines in the /util/getroot.c file.

   if (ent->d_name[0] == 'd' &&
       ent->d_name[1] == 'm' &&
       ent->d_name[2] == '-' &&
       ent->d_name[3] >= '0' &&
       ent->d_name[3] <= '9')
     continue;

Status changed to 'Confirmed' because the bug affects multiple users.

Look here: http://savannah.gnu.org/bugs/?28149
"GRUB2 supports hybrid GPT. It has even a tool gptsync for manipulating MBR of hybrid GPT. However Hybrid GPT has to have protective entry in MBR as its first entry and I see no reason to break this rule, especially that hybrid GPT is just a kludge for legacy systems and often is worse as either GPT or MSDOS. So your partition table is just invalid. Contact the developpers of whatever tool created it and say that protective entry has to be the first one"