On 20.02.2017 17:01, Alexander Graf wrote: > > > On 20/02/2017 07:43, Thomas Huth wrote: >> On 20.02.2017 15:19, Cornelia Huck wrote: >>> This patchset implements network boot for s390x. You need to build >>> a s390-netboot.img to actually perform the work (not included). >> >> Do you plan to include this into the upstream QEMU repository later, or >> will this stay an external binary? >> >>> Basically, we add support for virtio-net devices into the ipl code >>> and update the ccw bios to handle this as well. >> >> Just out of curiosity: What's the reason for shipping an additional >> binary here? Couldn't it be linked into the ccw bios as well (so that >> it's easier for the user to select a different version with the -bios >> parameter)? > > The "other binary" (s390-netboot.img) is the equivalent of grub or > pxelinux in an x86 network boot environment. That one usually comes from > a different entity and different department :). I'd rather compare the other binary to an option ROM. At this point in time we there's no netboot ROM, but a set of instructions on how to build a netboot binary from a kernel and a ramdisk, the series coverletter contains a brief version of that.
> > I haven't looked at the patches in detail, but do they follow the > "normal" PXE boot flow? Do they do a DHCP request, send a proper > Vendor-Class-Identifier for s390x, fetch the binary described by the > "filename" property in the DHCP ack via TFTP from next-server and run > that one then? It's currently not described with that level of detail, but the idea is to skip the step of loading a syslinux equivalent, and to immediately fetch the PXELINUX config file from the TFT next server aka siaddr and load the kernel and ramdisk specified therein. I.e. a simulation of the PXELINUX process is done in a similar fashion to petitboot PXE boot. > > It would be very good to stick to that flow, so that you don't confuse > your network admins :). > > > Alex > -- Mit freundlichen Grüßen/Kind Regards Viktor Mihajlovski IBM Deutschland Research & Development GmbH Vorsitzender des Aufsichtsrats: Martina Köderitz Geschäftsführung: Dirk Wittkopp Sitz der Gesellschaft: Böblingen Registergericht: Amtsgericht Stuttgart, HRB 243294