Current support of zPCI in qemu is still a bit sketchy. For example, we're not actually advertising the pci cpu facilities to the guest, and therefore a Linux guest will not even try to use any pci devices. We're also still missing a proper SIC implementation.
This can lead to a situation where pci devices are configured for an instance but the guest user is not able to make proper use of them. In order to avoid such surprises, it makes sense to be able to configure out pci support for s390x so that no pci devices show up in the list of available devices. This RFC patch set (also available at github.com/cohuck/qemu no-zpci) tries to clean up some of the s390x pci intertwinings so that we can do a non-pci build by simply removing 'CONFIG_PCI=y' from the default config. It also removes a dependency on pci by kvm code, which is probably unintended (it seems all kvm platforms also support pci). Patch set is RFC as: - I'm not sure whether my fencing is architecturally correct, as I don't have access to the respective documentation, - I don't really like the #ifdeffery too much. Cornelia Huck (7): kvm: remove hard dependency on pci s390x: chsc nt2 events are pci-only s390x/sclp: properly guard pci-specific functions s390x/ccw: create s390 phb conditionally s390x/pci: fence off instructions for non-pci s390x/kvm: msi route fixup for non-pci s390x: refine pci dependencies default-configs/s390x-softmmu.mak | 2 +- hw/pci/pci-stub.c | 12 ++++++++++++ hw/s390x/Makefile.objs | 2 +- hw/s390x/s390-pci-bus.c | 4 ++-- hw/s390x/s390-pci-bus.h | 4 ++-- hw/s390x/s390-virtio-ccw.c | 9 +++++---- hw/s390x/sclp.c | 17 ++++++++++++++--- target/s390x/ioinst.c | 18 ++++++++++++++++++ target/s390x/kvm.c | 28 ++++++++++++++++++++++++++++ 9 files changed, 83 insertions(+), 13 deletions(-) -- 2.13.0
