Subject: Jessie live booting at 32 bit uefi PC ?

From: Hyeonjin Oh <[email-masked]>
Date: Wed, 31 Aug 2016 06:13:38 +0000

Thanks a lot, Debian team.

I have a question below.

Is jessie live possible to boot at 32 bit uefi PC ? (Most tablet with
baytrail CPU is only supporting 32 bit uefi boot)

---

From: "Thomas Schmitt" <[email-masked]>
Date: Wed, 31 Aug 2016 08:59:30 +0200

Hi,

Hyeonjin Oh wrote:
> Is jessie live possible to boot at 32 bit uefi PC ?

Only via "legacy" BIOS emulation.

Inspection of
  http://cdimage.debian.org/mirror/cdimage/archive/8.4.0-live/i386/iso-hybrid/debian-live-8.4.0-i386-standard.iso
shows that there are only boot entries which lure PC-BIOS:

- El Torito boot catalog with a single entry for platform "80x86"
  (which means PC-BIOS). This is used by BIOS when booting from
  optical media (CD, DVD, BD).

- Isohybrid MBR with a single partition starting at 512-block number 64
  and not being of type 0xef. (I.e. it is not the EFI System Partition and
  no valid GUID Partition Table is present.)
  The MBR program code is used by BIOS when booting from USB stick,
  memory card, or hard disk.

You could try whether a netinst ISO boots properly on your hardware:
  http://cdimage.debian.org/debian-cd/8.5.0/i386/iso-cd/debian-8.5.0-i386-netinst.iso
and if so, ask at
  [email-masked]
to give LiveCD the same boot equipment as netinst has.

There seems to be work in progress
  https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=731709
So my advise is not to complain in any way but rather to offer yourself
as tester of newest development.

Have a nice day :)

Thomas

---

From: Hyeonjin Oh <[email-masked]>
Date: Wed, 31 Aug 2016 07:12:58 +0000

Hi Thomas Schmitt, Thank you for fast feedback.

Have good day.

2016. 8. 31. 오후 3:58에 "Thomas Schmitt" <[email-masked]>님이 작성:

>   http://cdimage.debian.org/mirror/cdimage/archive/8.4.0-
> live/i386/iso-hybrid/debian-live-8.4.0-i386-standard.iso

---

From: Mark Fletcher <[email-masked]>
Date: Wed, 31 Aug 2016 14:02:51 +0000

On Wed, Aug 31, 2016 at 4:30 PM Hyeonjin Oh <[email-masked]> wrote:

> I can confirm recent experience, live CD couldn't boot UEFI but netinst
could. I used live CD to boot a new machine and build LFS until the grub
installation stage, when I discovered I couldn't install grub in UEFI mode
because none of the UEFI kernel "stuff" was available, so then I had to
boot netinst in UEFI mode, do a minimal Debian install to another USB key,
boot THAT, and use that to install grub on the disk of the machine
concerned, so I could get it to boot UEFI without re-doing the entire
installation of LFS. Live is great in all respects except that one.

I've got to think UEFI capability on the live images can't be far away,
since the netinst can already do it, and the number of machines that need
legacy boot is dwindling all the time (although still large, I'll warrant)
and there's a disturbing trend of new machines coming out with no legacy
compatibility mode.

Mark