Re: [Qemu-devel] [PATCH] nbd: use client_close() when negotiate phase fails

[Paolo Bonzini]

On 19/01/2016 12:50, Daniel P. Berrange wrote:
> 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 
>   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 

Good catch, thanks.

Paolo

> ---
>  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);
> 

[Qemu-devel] [PATCH] nbd: use client_close() when negotiate phase fails

[Daniel P. Berrange]

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 
  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 
---
 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