4.20-stable review patch. If anyone has any objections, please let me know.
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From: Toshiaki Makita makita.toshiaki@lab.ntt.co.jp
[ Upstream commit 8be4d9a492f88b96d4d3a06c6cbedbc40ca14c83 ]
Commit 4e09ff536284 ("virtio-net: disable NAPI only when enabled during XDP set") tried to fix inappropriate NAPI enabling/disabling when !netif_running(), but was not complete.
On error path virtio_net could enable NAPI even when !netif_running(). This can cause enabling NAPI twice on virtnet_open(), which would trigger BUG_ON() in napi_enable().
Fixes: 4941d472bf95b ("virtio-net: do not reset during XDP set") Signed-off-by: Toshiaki Makita makita.toshiaki@lab.ntt.co.jp Acked-by: Jason Wang jasowang@redhat.com Acked-by: Michael S. Tsirkin mst@redhat.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/virtio_net.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
--- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -2429,8 +2429,10 @@ static int virtnet_xdp_set(struct net_de return 0;
err: - for (i = 0; i < vi->max_queue_pairs; i++) - virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi); + if (netif_running(dev)) { + for (i = 0; i < vi->max_queue_pairs; i++) + virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi); + } if (prog) bpf_prog_sub(prog, vi->max_queue_pairs - 1); return err;