From: Akihiko Odaki <akihiko.odaki@daynix.com>
Date: Wed, 8 Jan 2025 12:13:29 +0000 (+0900)
Subject: virtio-net: Fix num_buffers for version 1
X-Git-Tag: v10.0.0-rc3~9^2~1
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=c17ad4b11bd268a35506cd976884562df6ca69d7;p=thirdparty%2Fqemu.git

virtio-net: Fix num_buffers for version 1

The specification says the device MUST set num_buffers to 1 if
VIRTIO_NET_F_MRG_RXBUF has not been negotiated.

Fixes: df91055db5c9 ("virtio-net: enable virtio 1.0")
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-Id: <20250108-buffers-v1-1-a0c85ff31aeb@daynix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---

diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index de87cfadff..340c6b6422 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -1999,6 +1999,8 @@ static ssize_t virtio_net_receive_rcu(NetClientState *nc, const uint8_t *buf,
                                     offsetof(typeof(hdr),
                                              virtio_net.hdr.num_buffers),
                                     sizeof(hdr.virtio_net.hdr.num_buffers));
+            } else {
+                hdr.virtio_net.hdr.num_buffers = cpu_to_le16(1);
             }
 
             guest_offset = n->has_vnet_hdr ?