On Tue, 4 Feb 2020 07:16:46 +0100 Thomas Huth <th...@redhat.com> wrote:
> On 04/02/2020 00.26, Paolo Bonzini wrote: > > > > > > Il mar 4 feb 2020, 00:20 Alexey Kardashevskiy <a...@ozlabs.ru > > <mailto:a...@ozlabs.ru>> ha scritto: > > > > Speaking seriously, what would I put into the guest? > > > > Only things that would be considered drivers. Ignore the partitions > > issue for now so that you can just pass the device tree services to QEMU > > with hypercalls. > > > > Netboot's dhcp/tftp/ip/ipv6 client? It is going to be another SLOF, > > smaller but adhoc with only a couple of people knowing it. > > > > > > You can generalize and reuse the s390 code. All you have to write is the > > PCI scan and virtio-pci setup. > > Well, for netbooting, the s390-ccw bios uses the libnet code from SLOF, > so re-using this for a slim netboot client on ppc64 would certainly be > feasible (especially since there are also already virtio drivers in SLOF > that are written in C), but I think it is not very future proof. The > libnet from SLOF only supports UDP, and no TCP. So for advanced boot > scenarios like booting from HTTP or even HTTPS, you need something else > (i.e. maybe grub is the better option, indeed). That makes me wonder what that means for s390: We're inheriting libnet's limitations, but we don't have grub -- do we need to come up with something different? Or improve libnet?