Hi,

I just bought a shiny new HP Pavilion G7 laptop for a client. It's a quite powerful machine, at least compared to my usual battered hardware: Intel Core i5 processor and 4 GB RAM.

First installation procedures ended in a complete mess. I had to fiddle around with the BIOS, which apparently likes to make the user jump through burning loops to disable UEFI (User Exasperating Fucking Insanity).

Now I'm at least able to get Slackware to boot, after having used gdisk for partitioning.

Good news: the 'huge' kernel will boot the thing OK.

Bad news: I can't seem to configure the generic-kernel-plus-initrd combination... which I've already done on (literally) hundreds of installs. Usually I edit mkinitrd.conf, fill out the right values, build the initrd with mkinitrd, and then add a stanza in lilo.conf. This time, I systematically get treated to a nice kernel panic on boot.

Now I wonder: is there some additional step involved when building an initrd with a GPT disk? I confess I'm completely clueless here.

Eventually, I "solved" the problem by simply rebuilding a kernel for the machine, without an initrd. I started from the generic kernel configuration and built ext4 and jbd into the kernel. Now it works.

Still, I'm puzzled.

You don't have to disable UEFI to boot slackware:

http://www.linuxquestions.org/questi...5/#post4885916

Also, slackware has had support for GPT disks for a good while now.

Yeah. But the question was: why can't I use an initrd in conjunction with a GPT disk?

Which bootloader do you use?

LILO. Currently booting my own custom kernel OK.

Lilo seems sometimes to have problems with GPT partitions can you try elilo?

You can't use LILO with UEFI/GPT. It doesn't work. You have to use ELILO.

Now the question remains: how on earth did I manage to boot this thing?

Well, you *can* use lilo in conjunction with GPT, this is stated very clearly in the installer's help, and that's what you did :-)

This is only with UEFI(*) that lilo doesn't work and elilo can be used instead.

(*) En Français: EUFI, Encore Une Fichue Invention.

Well LILO should work but sometimes it does not. That why ELILO is there.

Could you please elaborate a bit on sometimes? It would help owners of machines including GPT + possibly UEFI (which fortunately I do not belong :-)

Thank you everybody. Looks like this is sorted out.

Because LILO is not GPT aware it's more trial and error. I don't believe it's very clear why it's sometimes does not work.(well it wasn't made for it, so it's surprising that it often does work) a few quotes:

The still-older Linux Loader (LILO) doesn't explicitly support GPT, but its disk-addressing methods are based on sector locations, so it often does work (in practice).

Information on the old Linux Loader (LILO) and GPT is contradictory. Most sources say the two won't get along, but I've read others who opine that the combination does (or at least should) work fine, since LILO uses sector maps to point to the kernel file. My one attempt at this combination proved inconclusive. LILO was able to load and run the kernel, but the boot then failed with the kernel message mount: could not find filesystem '/dev/root'. This message followed messages that indicated that the computer's LVM configuration was working fine, but somehow handing off to the LVM-based root filesystem was a problem. A GRUB boot of this system worked fine.

Although LILO is indeed unaware of GPT tables (as of 23.1, the latest as of this writing), it appears that it might work on a system with GPT tables anyway. It doesn't really have to be aware. Here are some references sort of confirming this:

http://www.mail-archive.com/bug-parted@gnu.org/msg00993.html
http://www.justlinux.com/forum/showpost.php?s=a35ea34fa9a...
http://www.rodsbooks.com/gdisk/booting.html

Initially, I thought that it'd fail while being installed, but maybe not - or not always.

What was the solution?