On Thu, Jan 05, 2012 at 10:27:44AM +0100, Gerhard Wiesinger wrote: > On Thu, 5 Jan 2012, Gleb Natapov wrote: > > >On Thu, Jan 05, 2012 at 10:09:44AM +0100, Gerhard Wiesinger wrote: > >>On Thu, 5 Jan 2012, Gleb Natapov wrote: > >> > >>>On Thu, Jan 05, 2012 at 09:23:02AM +0100, Gerhard Wiesinger wrote: > >>>>On Thu, 5 Jan 2012, Gerd Hoffmann wrote: > >>>> > >>>>>On 01/04/12 19:02, Gerhard Wiesinger wrote: > >>>>>>Hello, > >>>>>> > >>>>>>I'm having the following boot order problem using an SCSI option ROM: > >>>>>> > >>>>> > >>>>>>Still boots the cdrom instead of harddisk. So it is impossible to have a > >>>>>>bootable CDROM in the VM without booting from it. > >>>>> > >>>>>-option-rom romfile=/root/roms/8xx_64.rom,bootindex=1 > >>>> > >>>>Ok, works well, but I think than "-boot order=c" is buggy, right? > >>>> > >>>Wrong. "-boot order=c" tells seabios to boot from a HD, but for that > >>>Seabios needs to actually know what is HD and what is not. Since Seabios > >>>does not support scsi controller natively it only sees pci device and > >>>has no idea that you have scsi disk there. It uses pci option rom to > >>>boot from this unknown device. > >> > >>But as far as I remember therefore the option ROM registers through > >>BIOS for INT 19h booting. So Seabios should know it that this is a > >>harddisk. > >It registers BEV. Otherwise you wouldn't be able to boot at all. In fact > >it registers multiple BEVs (one for each attached scsi device). But BIOS > >knows nothing about the device behind the BEV. It just jumps to BEV > >address to boot from it when INT 19h is called. There may be scsi cdrom > >there or even tape. > > But to get rid of this problem typical BIOSes have an option whether > they prefer to BOOT from SCSI (with an option ROM) or > from the other devices. Then the option ROM typically boots from the > first registered device. > > I think this is a missing feature in Seabios. > How is it missing if you just used it and confirmed that it worked?
-- Gleb.