Messages in this thread | | | Date | Tue, 16 Jun 2020 13:57:26 +0200 | From | Halil Pasic <> | Subject | Re: [PATCH v2 1/1] s390: virtio: let arch accept devices without IOMMU feature |
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On Tue, 16 Jun 2020 12:52:50 +0200 Pierre Morel <pmorel@linux.ibm.com> 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?
Regards, Halil
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