From 7b404cae7fa2850d476c29258f03b8e77a5b4bd0 Mon Sep 17 00:00:00 2001
From: Adrian Moreno <amorenoz@redhat.com>
Date: Tue, 24 Sep 2019 18:20:44 +0200
Subject: [PATCH] vhost-user: save features if the char dev is closed

That way the state can be correctly restored when the device is opened
again. This might happen if the backend is restarted.

Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1738768
Reported-by: Pei Zhang <pezhang@redhat.com>
Fixes: 6ab79a20af3a ("do not call vhost_net_cleanup() on running net from char user event")
Cc: ddstreet@canonical.com
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Adrian Moreno <amorenoz@redhat.com>
Message-Id: <20190924162044.11414-1-amorenoz@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
(cherry picked from commit c6beefd674fff8d41b90365dfccad32e53a5abcb)
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 net/vhost-user.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/net/vhost-user.c b/net/vhost-user.c
index 51921de443..014199d600 100644
--- a/net/vhost-user.c
+++ b/net/vhost-user.c
@@ -235,6 +235,10 @@ static void chr_closed_bh(void *opaque)

     s = DO_UPCAST(NetVhostUserState, nc, ncs[0]);

+    if (s->vhost_net) {
+        s->acked_features = vhost_net_get_acked_features(s->vhost_net);
+    }
+
     qmp_set_link(name, false, &err);

     qemu_chr_fe_set_handlers(&s->chr, NULL, NULL, net_vhost_user_event,
--
2.23.0