Lenovo BIOS boot fix

Allan Jude allanjude at freebsd.org
Sun Jul 12 05:57:23 UTC 2015

I have spent my weekend researching why my Lenovo X220s refuse to boot
from GPT partitioned disks.

Based on this mailing list post:

I have written a patch for gpart to change the way the PMBR is created.

Instead of writing the 0xee partition in the first slot (offset 0), it
writes it to the 2nd slot (offset 1).

This resolves the issue on my Lenovo X220s, and the installed image
boots fine on my T530, and various other non-lenovo amd64 machines at my

If others could please test this image (it is a pre-installed system, so
just dd it to a memory stick, and see if it boots. Can be safely done
without touching your disks), that would be most helpful.

compressed (193 MiB):

uncompressed (1 GiB):

Allan Jude

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 834 bytes
Desc: OpenPGP digital signature
URL: <http://lists.freebsd.org/pipermail/freebsd-current/attachments/20150712/0ff0c1df/attachment.bin>

More information about the freebsd-current mailing list