On Tue, Aug 6, 2024 at 8:25 PM Michael S. Tsirkin [off-list ref] wrote:

On Tue, Aug 06, 2024 at 10:22:24AM +0800, Jason Wang wrote:

quoted

We calculate guest offloads during probe without the protection of
rtnl_lock. This lead to race between probe and ndo_set_features. Fix
this by moving the calculation under the rtnl_lock.

Signed-off-by: Jason Wang <jasowang@redhat.com>

Fixes tag pls?

Fixes: 3f93522ffab2 ("virtio-net: switch off offloads on demand if
possible on XDP set")

Thanks

quoted

---
 drivers/net/virtio_net.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index fc5196ca8d51..1d86aa07c871 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c

@@ -6596,6 +6596,11 @@ static int virtnet_probe(struct virtio_device *vdev)
              netif_carrier_on(dev);
      }

+     for (i = 0; i < ARRAY_SIZE(guest_offloads); i++)
+             if (virtio_has_feature(vi->vdev, guest_offloads[i]))
+                     set_bit(guest_offloads[i], &vi->guest_offloads);
+     vi->guest_offloads_capable = vi->guest_offloads;
+
      rtnl_unlock();

      err = virtnet_cpu_notif_add(vi);

@@ -6604,11 +6609,6 @@ static int virtnet_probe(struct virtio_device *vdev)
              goto free_unregister_netdev;
      }

-     for (i = 0; i < ARRAY_SIZE(guest_offloads); i++)
-             if (virtio_has_feature(vi->vdev, guest_offloads[i]))
-                     set_bit(guest_offloads[i], &vi->guest_offloads);
-     vi->guest_offloads_capable = vi->guest_offloads;
-
      pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
               dev->name, max_queue_pairs);

--

2.31.1