virtio spec requires that all drivers set DRIVER_OK before using devices. While balloon isn't yet included in the virtio 1 spec, previous spec versions also required this. virtio balloon might violate this rule: probe calls kthread_run before setting DRIVER_OK, which might run immediately and cause balloon to inflate/deflate. To fix, call virtio_device_ready before running the kthread. Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx> --- drivers/virtio/virtio_balloon.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 5a6ad6d..6a356e3 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -508,6 +508,8 @@ static int virtballoon_probe(struct virtio_device *vdev) if (err < 0) goto out_oom_notify; + virtio_device_ready(vdev); + vb->thread = kthread_run(balloon, vb, "vballoon"); if (IS_ERR(vb->thread)) { err = PTR_ERR(vb->thread); -- MST _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization