From: Michael Brown <mbrown@fensystems.co.uk>
To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: Jordan Justen <jljusten@gmail.com>, qemu-devel <qemu-devel@nongnu.org>
Subject: Re: [Qemu-devel] OVMF, SeaBIOS & non-CSM based legacy boot
Date: Mon, 21 Mar 2011 21:17:55 +0000 [thread overview]
Message-ID: <201103212117.55762.mbrown@fensystems.co.uk> (raw)
In-Reply-To: <AANLkTikgV5oW=WpufrLi-Dqzx7k1A=AoOBNKZyoEDBfD@mail.gmail.com>
On Monday 21 Mar 2011 21:06:24 Stefan Hajnoczi wrote:
> On Mon, Mar 21, 2011 at 6:27 PM, Anthony Liguori <anthony@codemonkey.ws>
wrote:
> > On 03/21/2011 01:14 PM, Jordan Justen wrote:
> >> This weekend I spent some time working on loading SeaBIOS from OVMF to
> >> start a legacy boot. I was able to get x86& x86-64 Linux to legacy
> >> boot using this method.
> >>
> >> Unfortunately, (I think) it is not nearly as nice a having a true CSM.
> >> Basically, you have to decide at some point in the OVMF boot that you
> >> want to legacy boot, and once you start SeaBIOS running, OVMF/UEFI
> >
> > Interesting. How much time does OVMF add to the total boot time when
> > taking this approach?
> >
> >> will never be in the picture again (until system reset).
> >>
> >> Contrast this to using a CSM where you can:
> >> * Load a legacy option ROM (vbios, or disk rom),
> >> and use it during a UEFI boot
> >
> > Is there gPXE for UEFI yet?
>
> I have never tried it myself, but I think it should work. CCed
> Michael Brown to check.
Yes, iPXE for UEFI exists and works. Last tested by me about a week ago, on
various IBM UEFI systems.
Compared to a "legacy" BIOS network boot, you can't do anything very
interesting with UEFI. Features such as iSCSI, FCoE, AoE, HTTP all work with
a "legacy" BIOS but not with UEFI. A "legacy" BIOS network boot allows you to
boot an operating system; a UEFI network boot only allows you to boot an EFI
executable (which could be a second-stage OS loader).
UEFI as a platform has a long way to go before it matches the network boot
functionality available through iPXE in a "legacy" BIOS.
Michael
next prev parent reply other threads:[~2011-03-21 21:18 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-03-21 18:14 [Qemu-devel] OVMF, SeaBIOS & non-CSM based legacy boot Jordan Justen
2011-03-21 18:27 ` Anthony Liguori
2011-03-21 21:06 ` Stefan Hajnoczi
2011-03-21 21:17 ` Michael Brown [this message]
2011-03-21 21:31 ` Jordan Justen
2011-03-21 21:40 ` Stefan Hajnoczi
2011-03-21 23:14 ` Michael Brown
2011-03-21 21:23 ` Jordan Justen
2011-03-22 8:00 ` Gleb Natapov
2011-03-22 19:28 ` Jordan Justen
2011-03-22 20:07 ` Gleb Natapov
2011-03-22 21:53 ` Jordan Justen
2011-03-23 12:36 ` Gleb Natapov
2011-03-23 22:32 ` Jordan Justen
2011-03-24 11:53 ` Gleb Natapov
2011-03-24 16:46 ` Jordan Justen
2011-03-24 18:36 ` Gleb Natapov
2011-03-24 12:27 ` Michal Suchanek
2011-03-24 13:44 ` Gleb Natapov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=201103212117.55762.mbrown@fensystems.co.uk \
--to=mbrown@fensystems.co.uk \
--cc=jljusten@gmail.com \
--cc=qemu-devel@nongnu.org \
--cc=stefanha@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).