[PATCH] vhost-user: Silence unsupported VHOST_USER_PROTOCOL_F_RARP error

[Laurent Vivier]

In vhost_user_receive() if vhost_net_notify_migration_done() reports
an error we display on the console:

  Vhost user backend fails to broadcast fake RARP

This message can be useful if there is a problem to execute
VHOST_USER_SEND_RARP but it is useless if the backend doesn't
support VHOST_USER_PROTOCOL_F_RARP.

Don't report the error if vhost_net_notify_migration_done()
returns -ENOTSUP (from vhost_user_migration_done())

Update vhost_net-stub.c to return -ENOTSUP too.

Signed-off-by: Laurent Vivier <lviv...@redhat.com>
---
 hw/net/vhost_net-stub.c | 2 +-
 net/vhost-user.c        | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/hw/net/vhost_net-stub.c b/hw/net/vhost_net-stub.c
index 72df6d757e4d..875cd6c2b9c8 100644
--- a/hw/net/vhost_net-stub.c
+++ b/hw/net/vhost_net-stub.c
@@ -93,7 +93,7 @@ void vhost_net_config_mask(VHostNetState *net, VirtIODevice 
*dev, bool mask)
 
 int vhost_net_notify_migration_done(struct vhost_net *net, char* mac_addr)
 {
-    return -1;
+    return -ENOTSUP;
 }
 
 VHostNetState *get_vhost_net(NetClientState *nc)
diff --git a/net/vhost-user.c b/net/vhost-user.c
index 12555518e838..636fff8a84a2 100644
--- a/net/vhost-user.c
+++ b/net/vhost-user.c
@@ -146,7 +146,7 @@ static ssize_t vhost_user_receive(NetClientState *nc, const 
uint8_t *buf,
 
         r = vhost_net_notify_migration_done(s->vhost_net, mac_addr);
 
-        if ((r != 0) && (display_rarp_failure)) {
+        if ((r != 0) && (r != -ENOTSUP) && (display_rarp_failure)) {
             fprintf(stderr,
                     "Vhost user backend fails to broadcast fake RARP\n");
             fflush(stderr);
-- 
2.47.1