VIRTIO_RING_F_EVENT_IDX is a bit position value, but
virtio_init_device_vq populates vq->use_event_idx by ANDing this value
directly to vdev->features.
Fix the check for this flag in virtio_init_device_vq.
Reviewed-by: Andre Przywara <andre.przywara@xxxxxxx>
Signed-off-by: Tu Dinh Ngoc <dinhngoc.tu@xxxxxxx>
---
virtio/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/virtio/core.c b/virtio/core.c
index f432421..ea0e5b6 100644
--- a/virtio/core.c
+++ b/virtio/core.c
@@ -165,7 +165,7 @@ void virtio_init_device_vq(struct kvm *kvm, struct virtio_device *vdev,
struct vring_addr *addr = &vq->vring_addr;
vq->endian = vdev->endian;
- vq->use_event_idx = (vdev->features & VIRTIO_RING_F_EVENT_IDX);
+ vq->use_event_idx = (vdev->features & (1UL << VIRTIO_RING_F_EVENT_IDX));
vq->enabled = true;
if (addr->legacy) {
--
2.25.1
