From: Zigit Zo <zuozhijie@bytedance.com>
Date: Wed, 16 Jul 2025 11:57:17 +0000 (+0800)
Subject: virtio-net: fix recursived rtnl_lock() during probe()
X-Git-Tag: v6.16-rc7~37^2~8
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=be5dcaed694e4255dc02dd0acfe036708c535def;p=thirdparty%2Fkernel%2Flinux.git

virtio-net: fix recursived rtnl_lock() during probe()

The deadlock appears in a stack trace like:

  virtnet_probe()
    rtnl_lock()
    virtio_config_changed_work()
      netdev_notify_peers()
        rtnl_lock()

It happens if the VMM sends a VIRTIO_NET_S_ANNOUNCE request while the
virtio-net driver is still probing.

The config_work in probe() will get scheduled until virtnet_open() enables
the config change notification via virtio_config_driver_enable().

Fixes: df28de7b0050 ("virtio-net: synchronize operstate with admin state on up/down")
Signed-off-by: Zigit Zo <zuozhijie@bytedance.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://patch.msgid.link/20250716115717.1472430-1-zuozhijie@bytedance.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 5d674eb9a0f2c..82b4a2a2b8c42 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -7059,7 +7059,7 @@ static int virtnet_probe(struct virtio_device *vdev)
 	   otherwise get link status from config. */
 	netif_carrier_off(dev);
 	if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
-		virtnet_config_changed_work(&vi->config_work);
+		virtio_config_changed(vi->vdev);
 	} else {
 		vi->status = VIRTIO_NET_S_LINK_UP;
 		virtnet_update_settings(vi);