See the previous patch for a longer description of the deadlock.  Now
that QIONetListener supports waiting for clients in the main loop
AioContext, NBD can use that to ensure that the server can make
progress even when a client is intentionally starving the GMainContext
from any activity not tied to an AioContext.

Fixes: https://gitlab.com/qemu-project/qemu/-/issues/3169
Signed-off-by: Eric Blake <eblake@redhat.com>

---
v2: new patch
---
 blockdev-nbd.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/blockdev-nbd.c b/blockdev-nbd.c
index 1e3e634b87d..696474aea93 100644
--- a/blockdev-nbd.c
+++ b/blockdev-nbd.c
@@ -94,10 +94,10 @@ static void nbd_update_server_watch(NBDServerData *s)
 {
     if (s->listener) {
         if (!s->max_connections || s->connections < s->max_connections) {
-            qio_net_listener_set_client_func(s->listener, nbd_accept, NULL,
+            qio_net_listener_set_client_aio_func(s->listener, nbd_accept, NULL,
                                              NULL);
         } else {
-            qio_net_listener_set_client_func(s->listener, NULL, NULL, NULL);
+            qio_net_listener_set_client_aio_func(s->listener, NULL, NULL, NULL);
         }
     }
 }
-- 
2.51.1

On Sat, Nov 08, 2025 at 04:59:32PM -0600, Eric Blake wrote:
> See the previous patch for a longer description of the deadlock.  Now
> that QIONetListener supports waiting for clients in the main loop
> AioContext, NBD can use that to ensure that the server can make
> progress even when a client is intentionally starving the GMainContext
> from any activity not tied to an AioContext.
> 
> Fixes: https://gitlab.com/qemu-project/qemu/-/issues/3169
> Signed-off-by: Eric Blake <eblake@redhat.com>
> 
> ---
> v2: new patch
> ---
>  blockdev-nbd.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>


With regards,
Daniel
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