Re: Partitioning Mac drives
On Fri, 2 May 2014, John Paul Adrian Glaubitz wrote:
> On 05/02/2014 03:16 PM, Finn Thain wrote:
> > But if you end up using Emile instead of Penguin, hopefully you won't
> > need your kernels on an HFS partition, because you can then avoid
> > Penguin and therefore avoid MacOS.
> Haven't tried Emile so far. I wouldn't yet know how to install it. I
> just wanted to get the Mac boot into Debian for some tests first.
Even when using Emile, I keep the MacOS/Penguin partition for recovery
purposes. I expect Emile would work on your Centris 650, based on my
testing some years back.
> > If, having booted into MacOS (e.g. from CDROM), you find that the HFS
> > partitions are no longer visible in Finder then you have a different
> > problem.
> No, the partitions never showed up in MacOS again. In fact, I couldn't
> even select the disk in Hard Disk Toolkit anymore to erase or
> repartition it, very strange.
If Hard Disk Toolkit (or Drive Setup or SCSI Probe) can't detect the
device on the SCSI bus then there's probably a SCSI issue (bus
termination, device numbering...)
> I assume I will have to completely erase the disk for the Mac to
> recognize it again.
I would be suprised if that's the case. In anycase, if the SCSI device
can't be probed, you won't be able to do so.
> >> Anyone has any idea what could have happened? Did the additional
> >> partitioning mess up the partition table or
> > Are the partitions visible in the MacOS partition tools? If no
> > partitions show up in Disk Utility, then I'd say gparted may have
> > changed the partition map format from Apple Partition Map to DOS.
> Crawling through the logs on my Debian desktop where I connected the
> drive, this was the partition layout directly after attaching the disk
> for the first time:
> May 2 13:25:57 z6 kernel: [1993556.470074] sdg: [mac] sdg1 sdg2 sdg3 sdg4
> Interestingly, gparted only displayed three partitions, sdg3 being the
> HFS partition and sdg1 and sdf2 being unknown partition types. Any idea
> what these could be? Are those created by the MacOS disk utility to
> install the filesystem driver?
The disk drivers, actually. You can use Hard Disk Toolkit or the Apple
drive setup tools to re-install disk drivers into the appropriate
partition(s), in case they got corrupted by gparted.
BTW, driver partitions do have their own partition types (Apple_Driver and
Apple_Driver43 as opposed to Apple_HFS, Apple_UNIX_SVR2 etc).
> After adding three additional partitions (ext4, swap, btrfs), gparted
> showed a total number of 6 partitions while the kernel recognized 8
> partitions on re-attaching the disk:
> May 2 13:32:04 z6 kernel: [1993922.977602] sdg: [mac] sdg1 sdg2 sdg3
> sdg4 sdg5 sdg6 sdg7 sdg8
> After running gparted once, /proc/partitions shows the same partitions
> as gparted. So something seems somewhere off.
Sounds promising. Under Linux, mac-fdisk is useful to see the partition
map in detail. Under MacOS, Penguin and pdisk can also list partition map
information. See http://mac.linux-m68k.org/docs/faq.php#sec-11 for
> >> is HFS support in the Linux kernel broken?
> > Not AFAIK. But if you create the MacOS filesystem under Linux, you
> > will need an HFS filesystem (not HFS Plus) for a m68k Mac to boot from
> > it:
> So, doing the full partitioning on Linux should work in principle,
> shouldn't it?
I don't know. ISTR that the ROM attempts to load drivers from the driver
partitions at startup. If there are none, I guess YMMV depending on the
But none of this matters once Linux boots. E.g. if you had a disk
dedicated to Linux and a disk dedicated to MacOS, it would not matter what
the Linux disk looked like (e.g. DOS partition map would be fine). But the
MacOS disk would almost certainly need to be partitioned using a MacOS
> I remember having similar problems with gparted and Amiga disks where
> partitions created on Linux with gparted were not shown in AmigaOS until
> the partition type was set to a specific value. There weren't even shown
> as "NON-DOS". However, once using the proper options in gparted, I could
> do all Amiga partitioning on Linux with gparted before putting the disk
> back into my Amiga.
> I will try to partition another disk with gparted on the PC, then see if
> the Mac recognizes it. If it doesn't, I will file a bug report against
> libparted with detailed debug information providing dumps of the disk
> partitioned on MacOS as well as with gparted.
My guess would be that gparted can't create valid Apple_Driver partitions
in the absence of a re-distributable binary driver to install there.
However, if it turns out that an existing driver partition got corrupted
by gparted, I'd agree that there's a bug; one would expect gparted to