On 2020-06-16 14:17, Cornelia Huck wrote:
On Tue, 16 Jun 2020 13:57:26 +0200
Halil Pasic <pasic@xxxxxxxxxxxxx> wrote:
On Tue, 16 Jun 2020 12:52:50 +0200
Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
int virtio_finalize_features(struct virtio_device *dev)
{
int ret = dev->config->finalize_features(dev);
@@ -179,6 +184,10 @@ int virtio_finalize_features(struct virtio_device *dev)
if (!virtio_has_feature(dev, VIRTIO_F_VERSION_1))
return 0;
+ if (arch_needs_iommu_platform(dev) &&
+ !virtio_has_feature(dev, VIRTIO_F_IOMMU_PLATFORM))
+ return -EIO;
+
Why EIO?
Because I/O can not occur correctly?
I am open to suggestions.
We use -ENODEV if feature when the device rejects the features we
tried to negotiate (see virtio_finalize_features()) and -EINVAL when
the F_VERSION_1 and the virtio-ccw revision ain't coherent (in
virtio_ccw_finalize_features()). Any of those seems more fitting
that EIO to me. BTW does the error code itself matter in any way,
or is it just OK vs some error?
If I haven't lost my way, we end up in the driver core probe failure
handling; we probably should do -ENODEV if we just want probing to fail
and -EINVAL or -EIO if we want the code to moan.
what about returning -ENODEV and add a dedicated warning here?
--
Pierre Morel
IBM Lab Boeblingen
