See the patch for why nested AioContext locking is no longer allowed.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-id: 20171207201320.19284-3-stefanha@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>