Arch Linux

stewSquared

Member

Registered: 2011-07-05

Posts: 16

Failing to boot GPT disk with Legacy BIOS and syslinux on Thinkpad P50

Hi there! I'm installing Arch on a new Thinkpad P50. I've chosen to go with syslinux and GPT, mostly because it's familiar, simple to set up and has worked for me with no problems before (On my older thinkpads -- the T410 and T440s). I've run through all the steps as usual, but I can't boot arch. I've searched all over, read a few threads and have double-checked everything and can't find any mistakes.

To start, secure boot is turned off. I have my BIOS set to boot from Legacy MBR only and ignore UEFI. I have 2 m.2 ssd ports, one of which is occupied by the disk (UEFI) that came with windows pre-installed. The other only has arch linux.

When I was installing syslinux with `syslinux-install_update -i -a -m` I was told the script couldn't mark the boot partition active (yes, I have gptfdisk installed), so I just set that manually with gdisk and ran again with `-i -m`. But I noticed that it had copied `mbr.bin` instead of `gptmbr.bin`, so I installed that bit manually as well.

It still didn't boot, so I've gone ahead and marked the protective MBR as active (wasn't necessary on older laptops). The pmbr_boot flag shows up in parted, and gdisk gives me a warning that this is technically a violation of the GPT specification, but I don't see anything with `fdisk -l` (I do see the boot flag on the live usb).

I can't copy from that terminal, so I've included a few screenshots with relevant info: https://goo.gl/photos/3VhPs5UukNvnvWqg6

Any idea what's wrong? Is there an extra check in the BIOS of newer thinkpads that I need to be clever about?

Head_on_a_Stick

Member

From: London

Registered: 2014-02-20

Posts: 7,732

Website

Re: Failing to boot GPT disk with Legacy BIOS and syslinux on Thinkpad P50

I am not familiar with syslinux but I know that non-UEFI booting on GPT disks with GRUB is firmware-dependent and may not be possible at all.
https://wiki.archlinux.org/index.php/GU … OS_systems

I would recommend attempting a UEFI installation with /boot mounted to the already extant EFI system partition on your Windows drive but you should probably await the advice of somebody who actually uses syslinux.

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Are you infected with Wetiko?

stewSquared

Member

Registered: 2011-07-05

Posts: 16

Re: Failing to boot GPT disk with Legacy BIOS and syslinux on Thinkpad P50

Thanks for the reply, though I think I just figured it out! I'm using a fancy new NVMe drive. Apparently, you need to use UEFI for that. I found a workaround, but at this point, it sounds simpler just to make the move to UEFI: http://mrlithium.blogspot.com/2015/12/h … -bios.html