From e16d506fda2cd06925ae932cdd910f4072831c8c Mon Sep 17 00:00:00 2001 From: Toshiaki Makita Date: Tue, 29 Jan 2019 09:45:53 +0900 Subject: [PATCH] virtio_net: Don't enable NAPI when interface is down [ 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 Acked-by: Jason Wang Acked-by: Michael S. Tsirkin Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/virtio_net.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 215696f21d67..c504487c8245 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -2034,8 +2034,10 @@ static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog, 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;