[PATCH] virtio-rng: make device ready before making request

[Jason Wang]

Current virtio-rng does a entropy request before DRIVER_OK, this
violates the spec and kernel will ignore the interrupt after commit
8b4ec69d7e09 ("virtio: harden vring IRQ").

Fixing this by making device ready before the request.

Fixes: 8b4ec69d7e09 ("virtio: harden vring IRQ")
Reported-and-tested-by: syzbot+5b59d6d459306a556f54@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
---
 drivers/char/hw_random/virtio-rng.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/char/hw_random/virtio-rng.c b/drivers/char/hw_random/virtio-rng.c
index e856df7e285c..a6f3a8a2aca6 100644
--- a/drivers/char/hw_random/virtio-rng.c
+++ b/drivers/char/hw_random/virtio-rng.c
@@ -159,6 +159,8 @@ static int probe_common(struct virtio_device *vdev)
 		goto err_find;
 	}
 
+	virtio_device_ready(vdev);
+
 	/* we always have a pending entropy request */
 	request_entropy(vi);
 
-- 
2.25.1