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.
