When nbd_negotiate() fails, nbd_co_client_start() is directly calling client->close(). This eventually ends up calling nbd_client_put(), which does an assert(client->closing). Unfortunately we have not set the 'closing' flag, so the code now aborts. This bug was accidentally introduced in
commit ee7d7aabdaea4484e069cb99c9fc54e8cb24b56f Author: Fam Zheng <f...@redhat.com> Date: Thu Jan 14 16:41:01 2016 +0800 nbd: Always call "close_fn" in nbd_client_new The simple fix is to not directly call client->close() but instead call the client_close() method, which takes care todo the right sequence of steps to close the client. Signed-off-by: Daniel P. Berrange <berra...@redhat.com> --- nbd/server.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/nbd/server.c b/nbd/server.c index eead339..c29ba5f 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -1080,8 +1080,7 @@ static coroutine_fn void nbd_co_client_start(void *opaque) nbd_export_get(exp); } if (nbd_negotiate(data)) { - shutdown(client->sock, 2); - client->close(client); + client_close(client); goto out; } qemu_co_mutex_init(&client->send_lock); -- 2.5.0