Bug 470457

Summary:	The installation partitioner offers to delete GPT with default answer "yes"
Product:	[openSUSE] openSUSE 11.2	Reporter:	Dimitar Pashov <d.pashov>
Component:	Installation	Assignee:	Katarina Machalkova <kmachalkova>
Status:	RESOLVED FIXED	QA Contact:	Jiri Srain <jsrain>
Severity:	Minor
Priority:	P4 - Low	CC:	aschnell
Version:	unspecified
Target Milestone:	---
Hardware:	All
OS:	openSUSE 11.1
Whiteboard:
Found By:	---	Services Priority:
Business Priority:		Blocker:	---
Marketing QA Status:	---	IT Deployment:	---

Description Dimitar Pashov 2009-01-29 00:54:58 UTC

User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-GB; rv:1.9.0.5) Gecko/2008121300 SUSE/3.0.5-2.5 Firefox/3.0.5

This is something available since at least 11.0 but I've always kept forgetting it.
I have a MacBook Pro and every time I install openSUSE on it I get message of the sort:
"You hard disk is paritioned with the GUID Partition Table (GPT). Most BIOSes do not cannot recognize GPT. Would you like to conver it to MBR?"
Yes No

"Yes" is the default answer.

Now my point is that this message and the default answer are very much out of place. My arguments are:

1. Intel macs use GPT for a number of good reasons. MBR on the boot disk is not very well supported on those machines. It works but with glitches and I doubt apple is willing to improve on that, so MBR it is not really a good option.

2. Linux works fine with GPT there was a small issue with GRUB addressing partitions beyond the fourth but even this is fixed now, so there is no problem with using opensuse (or most other distributions) on GPT partitioned drivers.

3. If GPT partiotioned drive is found on non apple and non itanium hardware it most likely means that someone intentionally did it and knows what (s)he is doing, so I don't see the need of that message in that case as well.

4. Replacing the partiotion table means loosing all partitions, all data on the computer. That truly a disaster and if I was a new curious user without much clue I would truly "love" linux and opensuse after pressing the recommended "Yes" button. Based on that I would expect the number of opensuse installations on intel macs to be lower than the other major distributions.

I have two alternative solutions. Either drop the warning altogether because of (4.) or don't show if the machine is mac.

Reproducible: Always

Steps to Reproduce:
1. Try to install openSUSE 11.0 or higher on intel mac with GPT partitioned hard drive.
2. Enter the partition manager set the mounts and save changes
3. The window with the warning/proposition appers.
Actual Results:
I haven't went that far as to press "yes" but according to what is written I guess it will delete my GPT and create a new MBR.

Expected Results:
Either drop the warning altogether because of the reson expressed in 4. or don't show if the machine is an intel mac.

In case you want to send me some patches I'll be glad to help testing. I can also go in irc if you have more questions.

Comment 1 Katarina Machalkova 2009-02-26 17:53:35 UTC

This message is among those that have been modified few weeks ago, so that the question now reads "Do you want to keep GPT partition table?" and answering Yes means continuing the installation - at least tiny improvement :)

I did some code archeology and found out that the message has been introduced because of bug #47485 (wow, almost 6 years old) - which looks like combination of buggy GRUB and buggy BIOS.

Don't know how much the situation improved on the side of BIOSes, but if the GRUB issue has been fixed in the meantime, we can safely remove the warning, I believe.
Otherwise, we have to extend our architecture detection tools to recognize Intel on Apple hw.

Comment 2 Arvin Schnell 2009-02-26 18:53:26 UTC

The message can be removed. openSUSE 11.1 supports GPT even with older
BIOSes, see fate #303026: Parted was enhanced to write a compatibility
MBR when using GPT. So booting should work.

Comment 3 Dimitar Pashov 2009-02-26 20:18:11 UTC

yes opensuse recognizes gpt even from earlier and parted worked fine for a long time. I think the only thing to keep in mind here is grub.
Intel macs' bios emulator has limited mbr support. It can only handle primary partitions. Mbr on the other hand can only have 4 primary partitions. The situation by now looks like that one can have many many partitions with gpt. They are all 'real'(primary) but the so called pmbr (p for protective) can only hold the first four. Installing grub on the mbr on a mac might have bad consequences so it is necessary to install it on the 3-rd or 4-th partition if available. Once properly installed a recent grub will be able to see all other partitions if need be. 
Other issue is that parted might not be able to resize macs fs (hfs+ journaled) so it might be useful to have some warning that directs people to apple's resizing utility (it is part of the bootcamp program on mac ox s 10.5.x) the people who try to directly install without being aware about that. It looks like this more of an feature request now.

Comment 4 Katarina Machalkova 2009-03-02 16:30:02 UTC

The message is gone. Happy installing :)

> Other issue is that parted might not be able to resize macs fs (hfs+ journaled)
> so it might be useful to have some warning that directs people to apple's
> resizing utility 

Hmm, I never tried to test resizing hfs partition with YaST (no Apple machines around), but looking at the partitioner code, I guess a generic message saying something along "This partition does not support resizing" lines pops up.

Anyway, please file a separate enh. request if you think the message should be more informative (e.g. point person to apple-specific resize utility), or if it does not work out for any reason.