On 04.05.2012, at 16:02, Christian Borntraeger wrote: > On 04/05/12 16:00, Christian Borntraeger wrote: >>>> An IPL (booting) on s390 of SCSI disks is done by a firmware component. >>>> Lets implement this scheme as an qemu device that also allows to >>>> configure the IPL like the HMC. We have a parameter iplid that >>>> refers to a disk device and a load parm that specifies the entry >>>> on the disk to be ipled. We also provide a default device >>>> if no -device s390-ipl statement is given. >>> >>> Any reason we can't do this in guest firmware code? >> >> Conceptually guest firmware does not exist in the guest address space >> on s390. It is separate in a storage area called HSA. >> (you could say the existing hardware is semi-hosted, you cant buy it bare >> metal. >> Doing the boot code in guest address space will fail if the guest firmware >> address collides with the addresses specified by a bootmap. > > Or in other words, this code is closer to the real s390 boxes.
Yeah, I see the point. I'd really like to get Anthony's comments on this one first though. Alex
