Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756152Ab3GCM0i (ORCPT ); Wed, 3 Jul 2013 08:26:38 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42760 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752990Ab3GCM0h (ORCPT ); Wed, 3 Jul 2013 08:26:37 -0400 From: Jason Wang To: rusty@rustcorp.com.au, mst@redhat.com, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Jason Wang , Sasha Levin Subject: [PATCH net] virtio-net: fix the race between channels setting and refill Date: Wed, 3 Jul 2013 20:15:52 +0800 Message-Id: <1372853752-41889-1-git-send-email-jasowang@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1885 Lines: 54 Commit 55257d72bd1c51f25106350f4983ec19f62ed1fa (virtio-net: fill only rx queues which are being used) tries to refill on demand when changing the number of channels by call try_refill_recv() directly, this may race: - the refill work who may do the refill in the same time - the try_refill_recv() called in bh since napi was not disabled Which may led guest complain during setting channels: virtio_net virtio0: input.1:id 0 is not a head! Solve this issue by scheduling a refill work which can guarantee the serialization of refill. Cc: Sasha Levin Cc: Rusty Russell Cc: Michael S. Tsirkin Signed-off-by: Jason Wang --- drivers/net/virtio_net.c | 5 +---- 1 files changed, 1 insertions(+), 4 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index c9e0038..47b4882 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -901,7 +901,6 @@ static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs) struct scatterlist sg; struct virtio_net_ctrl_mq s; struct net_device *dev = vi->dev; - int i; if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ)) return 0; @@ -915,10 +914,8 @@ static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs) queue_pairs); return -EINVAL; } else { - for (i = vi->curr_queue_pairs; i < queue_pairs; i++) - if (!try_fill_recv(&vi->rq[i], GFP_KERNEL)) - schedule_delayed_work(&vi->refill, 0); vi->curr_queue_pairs = queue_pairs; + schedule_delayed_work(&vi->refill, 0); } return 0; -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/