3.16.70-rc1 review patch. If anyone has any objections, please let me know.
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From: Halil Pasic <pasic@xxxxxxxxxxxxx>
commit 3438b2c039b4bf26881786a1f3450f016d66ad11 upstream.
A queue with a capacity of zero is clearly not a valid virtio queue.
Some emulators report zero queue size if queried with an invalid queue
index. Instead of crashing in this case let us just return -ENOENT. To
make that work properly, let us fix the notifier cleanup logic as well.
Signed-off-by: Halil Pasic <pasic@xxxxxxxxxxxxx>
Signed-off-by: Cornelia Huck <cohuck@xxxxxxxxxx>
Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
[bwh: Backported to 3.16: adjust filename]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/s390/kvm/virtio_ccw.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/s390/kvm/virtio_ccw.c
+++ b/drivers/s390/kvm/virtio_ccw.c
@@ -258,6 +258,8 @@ static void virtio_ccw_drop_indicators(s
{
struct virtio_ccw_vq_info *info;
+ if (!vcdev->airq_info)
+ return;
list_for_each_entry(info, &vcdev->virtqueues, node)
drop_airq_indicator(info->vq, vcdev->airq_info);
}
@@ -386,7 +388,7 @@ static int virtio_ccw_read_vq_conf(struc
ccw->count = sizeof(struct vq_config_block);
ccw->cda = (__u32)(unsigned long)(vcdev->config_block);
ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_VQ_CONF);
- return vcdev->config_block->num;
+ return vcdev->config_block->num ?: -ENOENT;
}
static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
