On Fri, 22 Jul 2016 15:23:19 +0200 Greg Kurz <gr...@kaod.org> wrote: > On Fri, 22 Jul 2016 12:32:24 +0200 > Cornelia Huck <cornelia.h...@de.ibm.com> wrote: > > > On Fri, 22 Jul 2016 12:11:11 +0200 > > Greg Kurz <gr...@kaod.org> wrote: > > > > > On Fri, 22 Jul 2016 10:04:35 +0200 > > > Cornelia Huck <cornelia.h...@de.ibm.com> wrote: > > > > > > > On Thu, 21 Jul 2016 23:21:16 +0200 > > > > Greg Kurz <gr...@kaod.org> wrote: > > > > > > > > > From: Greg Kurz <gk...@linux.vnet.ibm.com> > > > > > > > > > > Without presuming if we got there because of a user mistake or some > > > > > more subtle bug in the tooling, it really does not make sense to > > > > > implement a non-functional device. > > > > > > > > > > Signed-off-by: Greg Kurz <gk...@linux.vnet.ibm.com> > > > > > Reviewed-by: Marcel Apfelbaum <mar...@redhat.com> > > > > > Signed-off-by: Greg Kurz <gr...@kaod.org> > > > > > --- > > > > > v4: - rephrased error message and provide a hint to the user > > > > > - split string literals to stay below 80 characters > > > > > - added Marcel's R-b tag > > > > > --- > > > > > hw/virtio/virtio-pci.c | 8 ++++++++ > > > > > 1 file changed, 8 insertions(+) > > > > > > > > > > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > > > > > index 755f9218b77d..72c4b392ffda 100644 > > > > > --- a/hw/virtio/virtio-pci.c > > > > > +++ b/hw/virtio/virtio-pci.c > > > > > @@ -1842,6 +1842,14 @@ static void virtio_pci_dc_realize(DeviceState > > > > > *qdev, Error **errp) > > > > > VirtIOPCIProxy *proxy = VIRTIO_PCI(qdev); > > > > > PCIDevice *pci_dev = &proxy->pci_dev; > > > > > > > > > > + if (!(virtio_pci_modern(proxy) || virtio_pci_legacy(proxy))) { > > > > > > > > > > > > > I'm not sure that I didn't mess up the sequence of the realize > > > > callbacks, but could disable_legacy still be AUTO here? In that case, > > > > we'd fail for disable-modern=on and disable-legacy unset (i.e., AUTO), > > > > which would be ok for pcie but not for !pcie. > > > > > > > > > > Marcel made the same comment in: > > > > > > https://lists.gnu.org/archive/html/qemu-devel/2016-07/msg05225.html > > > > > > If the user explicitly disables modern, she shouldn't rely on QEMU > > > implicitly enabling legacy, hence the suggestion in error_append_hint(). > > > > I don't know, I'd find that a bit surprising, especially as I would end > > up with a legacy-capable device if I did not specify anything in > > the !pcie case. > > > > Isn't it already what happens with legacy being the default in pre-2.7 QEMU ?
Well, that is exactly my point; users may be surprised. > > Do you think we should have separate checks for pcie and !pcie ? I don't think we should overengineer this. > > > > > > > > > + error_setg(errp, "device cannot work when both modern and > > > > > legacy modes" > > > > > + " are disabled"); > > > > Suggest to change this wording to: > > > > "device cannot work as neither modern nor legacy mode is enabled" > > > > as this more accurately reflects what happened (the user did not > > actively disable legacy in the case above). > > > > Thanks ! This is THE wording I was looking for :) :) I'm fine with the patch with the changed wording, as it less confusing for the user. <I'll be offline next week so please just attach my Reviewed-by: Cornelia Huck <cornelia.h...@de.ibm.com> if the only thing you change is the message>