On Mon, Mar 21, 2011 at 9:17 PM, Michael Brown <mbr...@fensystems.co.uk> wrote: > On Monday 21 Mar 2011 21:06:24 Stefan Hajnoczi wrote: >> On Mon, Mar 21, 2011 at 6:27 PM, Anthony Liguori <anth...@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).
Would it be possible to enable the more interesting things by registering as a network device or block device with UEFI? I don't know much about UEFI but I seem to remember that you can do that rather than being a pure bootloader that loads an EFI executable? Stefan
