On 09.08.2017 10:27, Cornelia Huck wrote: > On Wed, 9 Aug 2017 10:23:04 +0200 > Thomas Huth <th...@redhat.com> wrote: > >> On 09.08.2017 09:17, Cornelia Huck wrote: >>> Nothing in fsdev/ or hw/9pfs/ depends on pci; it should rather depend >>> on CONFIG_VIRTFS and on the presence of an appropriate virtio transport >>> device. >>> >>> Let's introduce CONFIG_VIRTIO_CCW to cover s390x and check for >>> CONFIG_VIRTFS && (CONFIG_VIRTIO_PCI || CONFIG_VIRTIO_CCW). >>> >>> Signed-off-by: Cornelia Huck <coh...@redhat.com> >>> --- >>> >>> Changes v1->v2: drop extraneous spaces, fix build on cris >>> >>> --- >>> default-configs/s390x-softmmu.mak | 1 + >>> fsdev/Makefile.objs | 9 +++------ >>> hw/Makefile.objs | 2 +- >>> 3 files changed, 5 insertions(+), 7 deletions(-) [...] >> >> Patch should be fine now, I think... >> >> But thinking about this again, I wonder whether it would be enough to >> simply check for CONFIG_VIRTIO=y here instead. CONFIG_VIRTIO=y should be >> sufficient to assert that there is also at least one kind of virtio >> transport available, right? >> Otherwise this will look really horrible as soon as somebody also tries >> to add support for virtio-mmio here later ;-) > > Do all virtio transports have support for 9p, though? I thought it was > only virtio-pci and virtio-ccw...
While virtio-pci and virtio-ccw seem to require separate dedicated devices (e.g. virtio-9p-pci and virtio-9p-ccw) for everything, virtio-mmio seems to work different. As far as I can see, there are no dedicated virtio-xxx-mmio devices in the code at all. According to https://www.redhat.com/archives/libvir-list/2013-August/msg00009.html you simply have to use virtio-xxx-device here instead. And a virtio-9p-device is available. So theoretically, the 9p code should work with virtio-mmio, too, or is there a problem that I did not see yet? Anyway, we likely should not blindly enable this, so unless somebody has a setup to test it, we should go with your current patch instead, I think. Thomas
