On Mon, Apr 18, 2022 at 5:17 AM Thomas Schmitt <scdbackup(a)gmx.net> wrote:
Hi,
Dominik 'Rathann' Mierzejewski wrote:
> > > Dell XPS 15 L502X 8GB RAM (BIOS only)
BIOS-only on a laptop might mean the firmware quirk which demands
to see the "boot/active" flag at some MBR partition table slot.
See a thread of grub-bug (and later grub-devel) from 2015/16
https://marc.info/?l=grub-bug&m=145052506901159&w=2
where Alexander E. Patrakov wrote:
"Subject: [bug #46716] Protective MBR partition is not marked as bootable
[...]
Changing the byte at offset 0x1be to 0x80 in the resulting iso makes
it bootable on such boards."
This led to the creation of xorrisofs option --mbr-force-bootable in
xorriso-1.4.3.
This sounds equivalent to the pbmr_boot option in parted. If so, it's
a catch-22 because without the bit set it means some buggy BIOS
systems won't boot; but with the bit set it means older versions of
Tianocore or anything based on Tianocore up until maybe 6 months ago,
won't boot.
--
Chris Murphy