[PATCH] virtio: rng: Check notifier helpers for VIRTIO_CONFIG_IRQ_IDX

[Mathieu Poirier]

Since the driver doesn't support interrupts, we must return early when
index is set to VIRTIO_CONFIG_IRQ_IDX.  Basically the same thing Viresh
did for "91208dd297f2 virtio: i2c: Check notifier helpers for
VIRTIO_CONFIG_IRQ_IDX".

Fixes: 544f0278afca ("virtio: introduce macro VIRTIO_CONFIG_IRQ_IDX")
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 hw/virtio/vhost-user-rng.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/hw/virtio/vhost-user-rng.c b/hw/virtio/vhost-user-rng.c
index 201a39e220c5..62142b717f73 100644
--- a/hw/virtio/vhost-user-rng.c
+++ b/hw/virtio/vhost-user-rng.c
@@ -129,6 +129,14 @@ static void vu_rng_guest_notifier_mask(VirtIODevice *vdev, 
int idx, bool mask)
 {
     VHostUserRNG *rng = VHOST_USER_RNG(vdev);
 
+    /*
+     * We don't support interrupts, return early if index is set to
+     * VIRTIO_CONFIG_IRQ_IDX.
+     */
+    if (idx == VIRTIO_CONFIG_IRQ_IDX) {
+        return;
+    }
+
     vhost_virtqueue_mask(&rng->vhost_dev, vdev, idx, mask);
 }
 
@@ -136,6 +144,14 @@ static bool vu_rng_guest_notifier_pending(VirtIODevice 
*vdev, int idx)
 {
     VHostUserRNG *rng = VHOST_USER_RNG(vdev);
 
+    /*
+     * We don't support interrupts, return early if index is set to
+     * VIRTIO_CONFIG_IRQ_IDX.
+     */
+    if (idx == VIRTIO_CONFIG_IRQ_IDX) {
+        return false;
+    }
+
     return vhost_virtqueue_pending(&rng->vhost_dev, idx);
 }
 
-- 
2.34.1