Messages in this thread |  | | From | Laurent Vivier <> | Subject | [PATCH 0/4] virtio_net: vdpa: update MAC address when it is generated by virtio-net | Date | Sun, 22 Jan 2023 11:05:22 +0100 |
| |
When the MAC address is not provided by the vdpa device virtio_net driver assigns a random one without notifying the device. The consequence, in the case of mlx5_vdpa, is the internal routing tables of the device are not updated and this can block the communication between two namespaces.
To fix this problem, use virtnet_send_command(VIRTIO_NET_CTRL_MAC) to set the address from virtnet_probe() when the MAC address is randomly assigned from virtio_net.
While I was testing this change I found 3 other bugs in vdpa_sim_net:
- vdpa_sim_net sets the VIRTIO_NET_F_MAC even if no MAC address is provided. So virtio_net doesn't generate a random MAC address and the MAC address appears to be 00:00:00:00:00:00
- vdpa_sim_net never processes the command and virtnet_send_command() hangs in an infinite loop. To avoid a kernel crash add a timeout in the loop.
- To allow vdpa_sim_net to process the command, replace the cpu_relax() in the loop by a schedule(). vdpa_sim_net uses a workqueue to process the queue, and if we don't allow the kernel to schedule, the queue is not processed and the loop is infinite.
Laurent Vivier (4): virtio_net: notify MAC address change on device initialization virtio_net: add a timeout in virtnet_send_command() vdpa_sim_net: don't always set VIRTIO_NET_F_MAC virtio_net: fix virtnet_send_command() with vdpa_sim_net
drivers/net/virtio_net.c | 21 +++++++++++++++++++-- drivers/vdpa/vdpa_sim/vdpa_sim_net.c | 6 ++++++ 2 files changed, 25 insertions(+), 2 deletions(-)
-- 2.39.0
|  |