From 93d389f82078cf7197152fb10d21977da0883420 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Thu, 27 Nov 2014 13:45:58 +0200 Subject: virtio: assert 32 bit features in transports At this point, no transports set any of the high 32 feature bits. Since transports generally can't (yet) cope with such bits, add BUG_ON checks to make sure they are not set by mistake. Based on rproc patch by Rusty. Signed-off-by: Rusty Russell Signed-off-by: Michael S. Tsirkin Reviewed-by: David Hildenbrand Reviewed-by: Cornelia Huck --- drivers/s390/kvm/kvm_virtio.c | 3 +++ drivers/s390/kvm/virtio_ccw.c | 3 +++ 2 files changed, 6 insertions(+) (limited to 'drivers/s390') diff --git a/drivers/s390/kvm/kvm_virtio.c b/drivers/s390/kvm/kvm_virtio.c index 2336c7e3b0cf..f5575ccdbb65 100644 --- a/drivers/s390/kvm/kvm_virtio.c +++ b/drivers/s390/kvm/kvm_virtio.c @@ -103,6 +103,9 @@ static void kvm_finalize_features(struct virtio_device *vdev) /* Give virtio_ring a chance to accept features. */ vring_transport_features(vdev); + /* Make sure we don't have any features > 32 bits! */ + BUG_ON((u32)vdev->features != vdev->features); + memset(out_features, 0, desc->feature_len); bits = min_t(unsigned, desc->feature_len, sizeof(vdev->features)) * 8; for (i = 0; i < bits; i++) { diff --git a/drivers/s390/kvm/virtio_ccw.c b/drivers/s390/kvm/virtio_ccw.c index 56d78956a8cb..244d611a0df2 100644 --- a/drivers/s390/kvm/virtio_ccw.c +++ b/drivers/s390/kvm/virtio_ccw.c @@ -714,6 +714,9 @@ static void virtio_ccw_finalize_features(struct virtio_device *vdev) /* Give virtio_ring a chance to accept features. */ vring_transport_features(vdev); + /* Make sure we don't have any features > 32 bits! */ + BUG_ON((u32)vdev->features != vdev->features); + features->index = 0; features->features = cpu_to_le32(vdev->features); /* Write the feature bits to the host. */ -- cgit v1.2.3-70-g09d2