On 2020-06-19 14:02, Halil Pasic wrote:

On Fri, 19 Jun 2020 11:20:51 +0200
Cornelia Huck [off-list ref] wrote:

quoted

quoted

quoted

+	if (arch_needs_virtio_iommu_platform(dev) &&
+		!virtio_has_feature(dev, VIRTIO_F_IOMMU_PLATFORM)) {
+		dev_warn(&dev->dev,
+			 "virtio: device must provide VIRTIO_F_IOMMU_PLATFORM\n");

I'm not sure, divulging the current Linux name of this feature bit is a
good idea, but if everybody else is fine with this, I don't care that

Not sure if that feature name will ever change, as it is exported in
headers. At most, we might want to add the new ACCESS_PLATFORM define
and keep the old one, but that would still mean some churn.

quoted

much. An alternative would be:
"virtio: device falsely claims to have full access to the memory,
aborting the device"

"virtio: device does not work with limited memory access" ?

But no issue with keeping the current message.

I think I prefer Conny's version, but no strong feelings here.

The reason why the device is not accepted without IOMMU_PLATFORM is arch 
specific, I think it should be clearly stated.
If no strong oposition...

Thanks,
Pierre


-- 
Pierre Morel
IBM Lab Boeblingen