Messages in this thread | | | From | (H. Peter Anvin) | Subject | Re: 3TB disk hassles | Date | Tue, 8 Feb 2005 23:33:51 +0000 (UTC) |
| |
Followup to: <20050206105958.42872.qmail@web26501.mail.ukl.yahoo.com> By author: Neil Conway <nconway_kernel@yahoo.co.uk> In newsgroup: linux.dev.kernel > > Since writing the above, I've been searching for more info. I > downloaded four different versions of grub (GNU Grub Legacy, GNU Grub2, > gentoo and Fedora Core 3). NONE of these showed any evidence of GPT > support (I was in a hurry, so I searched for strings EFI, GUID, GPT, > TB). > > Mucho confused puppy here. > > I fail to see how grub can work on a GPT boot device if it can't parse > the partition table. I conclude that I'm still missing something. > Perhaps a layer before grub is supposed to parse the GPT instead? If > so, isn't that getting us straight back to a GPT-aware BIOS? > > Tell me if this logic is broken: even if a special boot sector is used, > which IS GPT-aware (though fitting that into the boot sector would be a > challenge ;-)), once grub loads, it's still going to have to figure out > how to find the root(hdX,Y) partition from which to load the kernel > image. This surely means it has to have either a GPT-parser > internally, or rely on a pre-parsed list. No? > > Perhaps one of the other several distros (that I didn't check) has a > GPT-aware grub. But Tomas Carnecky said early in this thread that > gentoo had allowed him to set up a GPT-booting system on x86. I guess > it's possible that a cheat was used - maybe an old-style partition > table in the MBR was used to define the first (boot) partition, but > surely that's forbidden by the whole EFI spec anyway? >
No, it's encouraged.
> > Andries Brouwer kindly wrote a patch which I haven't had time to test > yet (see earlier in thread). While it would be nice to find a way > around the problem which didn't require deviations from vanilla > distros, I think Andries' patch is looking like the only sane fix right > now. >
Note that Andries' patch does *EXACTLY* the same thing as the GPT/EFI spec does (by using an old-style partition table for the first 2 TB.)
It should be pretty easy to add native support for this in EXTLINUX; the big problem is supporting true access > 2 TB, which I currently don't have any way to test.
I'll put that on my todo list.
-hpa - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |