On Fri, 4 Feb 2022 08:05:25 -0500
"Michael S. Tsirkin" <m...@redhat.com> wrote:
> On Thu, Feb 03, 2022 at 05:06:35PM +0100, Halil Pasic wrote:
> > On Wed, 2 Feb 2022 20:54:38 +0100
> > Halil Pasic <pa...@linux.ibm.com> wrote:
> >
> > > }
> > > @@ -82,9 +78,14 @@ void virtio_bus_device_plugged(VirtIODevice *vdev,
> > > Error **errp)
> > > return;
> > > }
> > >
> > > + vdev_has_iommu = virtio_host_has_feature(vdev,
> > > VIRTIO_F_IOMMU_PLATFORM);
> > > if (klass->get_dma_as != NULL && has_iommu) {
> > > virtio_add_feature(&vdev->host_features,
> > > VIRTIO_F_IOMMU_PLATFORM);
> > > vdev->dma_as = klass->get_dma_as(qbus->parent);
> > > + if (!vdev_has_iommu && vdev->dma_as != &address_space_memory) {
> > > + error_setg(errp,
> > > + "iommu_platform=true is not supported by the
> > > device");
> > > + }
> >
> > I'm wondering, would it be wise to change the message? Since this is now
> > dependent on the VM/bus the device is plugged into the message might be a
> > little misleading: i.e. the very same device could work perfectly fine
> > with iommu_platform=true if the "surroundings" are different.
> >
> > Maybe "the device has no IOMMU support (iommu_platform=true)" would be a
> > better option. On the other hand changing the message has its downsides
> > as well.
>
> I personally don't care much frankly.
>
> > Also I realized that keeping the return after error_setg() might have
> > been a good idea for the case more logic is added at the end of the
> > function.
>
> OK so you are sending v5 with this change then?
As stated below, I would prefer to get this merged. If I change the
message, I guess I have to drop the r-b's and the I'm sure the if
somebody decides to add logic to the end of the function that person
will be careful enough.
>
> > In any case I would like to address these, if necessary with a separate
> > patch. I don't want the fix to experience any further delays.
> >
> > Regards,
> > Halil
>
