[PATCH] fdisk: Add support for GPT partition type codes

[Mattias Schlenker]

Am 29.11.2016 um 08:58 schrieb James Bowlin:

> Aside from size constraints, etc, all four combinations work:
>
>    o UEFI booting on GPT partitioning
>    o UEFI booting on MSDOS partitioning
>    o Legacy booting on GPT partitioning
>    o Legacy booting on MSDOS partitioning
>
> For example, my live-usb-maker script:
> https://github.com/BitJam/live-usb-maker  boots via both legacy
> and UEFI and it can be set to partition with GPT or MSDOS.

In theory they work and in practice in 99% of the cases when booting 
internal hard drives. My preferred boot configuration on all PC systems 
are GPT partitioned drives with a partition markes EFI system and one 
marked legacy boot (might apply to the same partition) and using 
gptmbr.bin from syslinux to boot.

In practice there are some early EFIs (ca. 2007 to 2010) that are 
disguised as BIOS that ignore the 448 byte boot block on USB drives and 
instead look for a MBR partition table and one partition marked as 
active. Because of the protective MBR they won't boot a GPT partitioned 
stick. Something similar applies to many 32 bit UEFIs (cheap Intel 
tablets and netbooks). To boot from external media those expect a single 
partition drive, MBR partition table and the partition flagged as (EFI 
system partition) containing all the boot files. This might violate the 
UEFI standards, but I guess since Windows bootable USB drives use 
exactly this single partition MBR layout, no one cares in practice.

Yours,
Mattias

-- 
Mattias Schlenker - Freier IT-Fachredakteur und -autor
                              redaktion at mattiasschlenker.de
Mattias Schlenker - IT-Consulting, Softwareentwicklung
                             consulting at mattiasschlenker.de

Address__ August-Bebel-Str. 74 - D-04275 LEIPZIG - GERMANY
Phone: +49 341 39290767              Fax: +49 341 30393578
Mobile: +49 163  6953657  Another mobile: +49 159 03160327
VATIN_________________________________________ DE240998538

Fork me!____________________ https://github.com/mschlenker
Website.__________________ http://www.mattiasschlenker.de/
My books!___________ http://www.arduino-hausautomation.de/