On Thu, 21 Jul 2016 19:02:39 +0200
Greg Kurz <gr...@kaod.org> wrote:
> On Thu, 21 Jul 2016 19:52:28 +0300
> Marcel Apfelbaum <marcel.apfelb...@gmail.com> wrote:
>
> > On 07/21/2016 06:52 PM, Greg Kurz 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>
> > > Signed-off-by: Greg Kurz <gr...@kaod.org>
> > > ---
> > > v2: - error out at realize time as suggested by Connie
> > > - updated title and changelog
> > > ---
> > > hw/virtio/virtio-pci.c | 6 ++++++
> > > 1 file changed, 6 insertions(+)
> > >
> > > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
> > > index f0677b73d860..8d707aac0c21 100644
> > > --- a/hw/virtio/virtio-pci.c
> > > +++ b/hw/virtio/virtio-pci.c
> > > @@ -1838,6 +1838,12 @@ static void virtio_pci_dc_realize(DeviceState
> > > *qdev, Error **errp)
> > > VirtIOPCIProxy *proxy = VIRTIO_PCI(qdev);
> > > PCIDevice *pci_dev = &proxy->pci_dev;
> > >
> > > + if (proxy->flags & VIRTIO_PCI_FLAG_DISABLE_LEGACY &&
> > > + proxy->flags & VIRTIO_PCI_FLAG_DISABLE_MODERN) {
> > > + error_setg(errp, "device is unserviceable when both legacy and
> > > modern modes are disabled. At least one of the disable-modern or
> > > disable-legacy properties should be set to false.");
> > > + return;
> > > + }
> > > +
> >
> > Hi Greg,
> >
> > I agree with the patch, but other patch in the mailing list
> > replaces the flags with standalone fields:
> >
> > https://lists.gnu.org/archive/html/qemu-devel/2016-07/msg04744.html
> >
>
> v3 will be using virtio_pci_legacy() and virtio_pci_modern().
>
> > Also the error line may be too long and need to be truncated.
> >
>
> I'll rephrase the message. BTW is there a formal limit for the length
> of error lines ? 80 chars ?
>
Not even sure it makes sense since the final error message contains the
full -device command line option which can be of arbitrary length...
> > Thanks,
> > Marcel
> >
> > > if (!(proxy->flags & VIRTIO_PCI_FLAG_DISABLE_PCIE) &&
> > > !(proxy->flags & VIRTIO_PCI_FLAG_DISABLE_MODERN)) {
> > > pci_dev->cap_present |= QEMU_PCI_CAP_EXPRESS;
> > >
> > >
> >
>
