Re: [PATCH v5 2/2] s390: virtio: PV needs VIRTIO I/O device protection

From: Pierre Morel
Date: Thu Jul 09 2020 - 10:51:22 EST




On 2020-07-09 16:47, Halil Pasic wrote:
On Thu, 9 Jul 2020 12:51:58 +0200
Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:

+int arch_validate_virtio_features(struct virtio_device *dev)
+{
+ if (!is_prot_virt_guest())
+ return 0;
+
+ if (!virtio_has_feature(dev, VIRTIO_F_VERSION_1)) {
+ dev_warn(&dev->dev, "device must provide VIRTIO_F_VERSION_1\n");

I'd probably use "legacy virtio not supported with protected
virtualization".
+ return -ENODEV;
+ }
+
+ if (!virtio_has_feature(dev, VIRTIO_F_IOMMU_PLATFORM)) {
+ dev_warn(&dev->dev,
+ "device must provide VIRTIO_F_IOMMU_PLATFORM\n");

"support for limited memory access required for protected
virtualization"

?

Mentioning the feature flag is shorter in both cases, though.

And I think easier to look for in case of debugging purpose.
I change it if there is more demands.

Not all our end users are kernel and/or qemu developers. I find the
messages from v4 less technical, more informative, and way better.

Regards,
Halil


Can you please tell me the messages you are speaking of, because for me the warning's messages are exactly the same in v4 and v5!?

I checked many times, but may be I still missed something.

Regards,
Pierre


--
Pierre Morel
IBM Lab Boeblingen