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![Marc Hartmayer](/assets/img/avatar_default.png)
Since virtio existed even before it got standardized, the virtio standard defines the following types of virtio devices: + legacy device (pre-virtio 1.0) + non-legacy or VIRTIO 1.0 device + transitional device (which can act both as legacy and non-legacy) Virtio 1.0 defines the fields of the virtqueues as little endian, while legacy uses guest's native endian [1]. Currently libvhost-user does not handle virtio endianness at all, i.e. it works only if the native endianness matches with whatever is actually needed. That means things break spectacularly on big-endian targets. Let us handle virtio endianness for non-legacy as required by the virtio specification [1] and fence legacy virtio, as there is no safe way to figure out the needed endianness conversions for all cases. The fencing of legacy virtio devices is done in `vu_set_features_exec`. [1] https://docs.oasis-open.org/virtio/virtio/v1.1/cs01/virtio-v1.1-cs01.html#x1-210003 Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com> Message-id: 20200901150019.29229-3-mhartmay@linux.ibm.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>