[PATCH v4 04/42] virtio: disable virtio 1.0 in transports

["Michael S. Tsirkin" <mst@redhat.com>]

disable virtio 1.0 in transports that don't
support it yet.
We will gradually re-enable as support is added.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 drivers/lguest/lguest_device.c     | 3 ++-
 drivers/misc/mic/card/mic_virtio.c | 2 ++
 drivers/s390/kvm/virtio_ccw.c      | 3 ++-
 drivers/virtio/virtio_mmio.c       | 2 ++
 4 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/lguest/lguest_device.c b/drivers/lguest/lguest_device.c
index 4d29bcd..4deaf88 100644
--- a/drivers/lguest/lguest_device.c
+++ b/drivers/lguest/lguest_device.c
@@ -106,7 +106,8 @@ static u64 lg_get_features(struct virtio_device *vdev)
 		if (in_features[i / 8] & (1 << (i % 8)))
 			features |= (1ULL << i);
 
-	return features;
+	/* lguest is not in virtio 1.0 */
+	return features & ~BIT_ULL(VIRTIO_F_VERSION_1);
 }
 
 /*
diff --git a/drivers/misc/mic/card/mic_virtio.c b/drivers/misc/mic/card/mic_virtio.c
index 6d94f04..edc77f1 100644
--- a/drivers/misc/mic/card/mic_virtio.c
+++ b/drivers/misc/mic/card/mic_virtio.c
@@ -82,6 +82,8 @@ static u64 mic_get_features(struct virtio_device *vdev)
 		if (ioread8(&in_features[i / 8]) & (BIT_ULL(i % 8)))
 			features |= BIT_ULL(i);
 
+	/* MIC is not in virtio 1.0, disable it for now. */
+	features &= ~BIT_ULL(VIRTIO_F_VERSION_1);
 	return features;
 }
 
diff --git a/drivers/s390/kvm/virtio_ccw.c b/drivers/s390/kvm/virtio_ccw.c
index abba04d..08536f0 100644
--- a/drivers/s390/kvm/virtio_ccw.c
+++ b/drivers/s390/kvm/virtio_ccw.c
@@ -704,7 +704,8 @@ static u64 virtio_ccw_get_features(struct virtio_device *vdev)
 out_free:
 	kfree(features);
 	kfree(ccw);
-	return rc;
+	/* TODO: enable virtio 1.0 */
+	return rc & ~BIT_ULL(VIRTIO_F_VERSION_1);;
 }
 
 static void virtio_ccw_finalize_features(struct virtio_device *vdev)
diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
index fd01c6d..e1d38a9 100644
--- a/drivers/virtio/virtio_mmio.c
+++ b/drivers/virtio/virtio_mmio.c
@@ -151,6 +151,8 @@ static u64 vm_get_features(struct virtio_device *vdev)
 	features = readl(vm_dev->base + VIRTIO_MMIO_HOST_FEATURES);
 	writel(1, vm_dev->base + VIRTIO_MMIO_HOST_FEATURES_SEL);
 	features |= ((u64)readl(vm_dev->base + VIRTIO_MMIO_HOST_FEATURES) << 32);
+	/* TODO: enable virtio 1.0 support */
+	features &= ~BIT_ULL(VIRTIO_F_VERSION_1);
 	return features;
 }
 
-- 
MST