From 88660f7fb94cda1f8f63ee92bfcd0db39a6361e2 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Thu, 5 Mar 2015 13:24:41 +1030 Subject: [PATCH] virtio_balloon: set DRIVER_OK before using device 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 Signed-off-by: Rusty Russell Cc: stable@kernel.org --- 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 0413157f3b49..b36fe56677d5 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -499,6 +499,8 @@ 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); -- 2.34.1