Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754494AbaKSGgN (ORCPT ); Wed, 19 Nov 2014 01:36:13 -0500 Received: from mx1.redhat.com ([209.132.183.28]:48086 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751455AbaKSGgM (ORCPT ); Wed, 19 Nov 2014 01:36:12 -0500 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 , Cornelia Huck , Wanlong Gao Subject: [PATCH net] virtio-net: validate features during probe Date: Wed, 19 Nov 2014 14:35:39 +0800 Message-Id: <1416378939-28821-1-git-send-email-jasowang@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch validates feature dependencies during probe and fail the probing if a dependency is missed. This fixes the issues of hitting BUG() when qemu fails to advertise features correctly. One example is booting guest with ctrl_vq=off through qemu. Cc: Rusty Russell Cc: Michael S. Tsirkin Cc: Cornelia Huck Cc: Wanlong Gao Signed-off-by: Jason Wang --- drivers/net/virtio_net.c | 93 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 93 insertions(+) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index ec2a8b4..4a0ad46 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -1673,6 +1673,95 @@ static const struct attribute_group virtio_net_mrg_rx_group = { }; #endif +static int virtnet_validate_features(struct virtio_device *dev, + unsigned int *table, + int table_size, + unsigned int feature) +{ + int i; + + if (!virtio_has_feature(dev, feature)) { + for (i = 0; i < table_size; i++) { + unsigned int f = table[i]; + + if (virtio_has_feature(dev, f)) { + dev_err(&dev->dev, + "buggy hyperviser: feature 0x%x was advertised but its dependency 0x%x was not", + f, feature); + return -EINVAL; + } + } + } + + return 0; +} + +static int virtnet_check_features(struct virtio_device *dev) +{ + unsigned int features_for_ctrl_vq[] = { + VIRTIO_NET_F_CTRL_RX, + VIRTIO_NET_F_CTRL_VLAN, + VIRTIO_NET_F_GUEST_ANNOUNCE, + VIRTIO_NET_F_MQ, + VIRTIO_NET_F_CTRL_MAC_ADDR + }; + unsigned int features_for_guest_csum[] = { + VIRTIO_NET_F_GUEST_TSO4, + VIRTIO_NET_F_GUEST_TSO6, + VIRTIO_NET_F_GUEST_ECN, + VIRTIO_NET_F_GUEST_UFO, + }; + unsigned int features_for_host_csum[] = { + VIRTIO_NET_F_HOST_TSO4, + VIRTIO_NET_F_HOST_TSO6, + VIRTIO_NET_F_HOST_ECN, + VIRTIO_NET_F_HOST_UFO, + }; + int err; + + err = virtnet_validate_features(dev, features_for_ctrl_vq, + ARRAY_SIZE(features_for_ctrl_vq), + VIRTIO_NET_F_CTRL_VQ); + if (err) + return err; + + err = virtnet_validate_features(dev, features_for_guest_csum, + ARRAY_SIZE(features_for_guest_csum), + VIRTIO_NET_F_GUEST_CSUM); + if (err) + return err; + + err = virtnet_validate_features(dev, features_for_host_csum, + ARRAY_SIZE(features_for_host_csum), + VIRTIO_NET_F_CSUM); + if (err) + return err; + + if (virtio_has_feature(dev, VIRTIO_NET_F_GUEST_ECN) && + (!virtio_has_feature(dev, VIRTIO_NET_F_GUEST_TSO4) || + !virtio_has_feature(dev, VIRTIO_NET_F_GUEST_TSO6))) { + dev_err(&dev->dev, + "buggy hyperviser: feature 0x%x was advertised but its dependency 0x%x or 0x%x was not", + VIRTIO_NET_F_GUEST_ECN, + VIRTIO_NET_F_GUEST_TSO4, + VIRTIO_NET_F_GUEST_TSO6); + return -EINVAL; + } + + if (virtio_has_feature(dev, VIRTIO_NET_F_HOST_ECN) && + (!virtio_has_feature(dev, VIRTIO_NET_F_HOST_TSO4) || + !virtio_has_feature(dev, VIRTIO_NET_F_HOST_TSO6))) { + dev_err(&dev->dev, + "buggy hyperviser: feature 0x%x was advertised but its dependency 0x%x or 0x%x was not", + VIRTIO_NET_F_HOST_ECN, + VIRTIO_NET_F_HOST_TSO4, + VIRTIO_NET_F_HOST_TSO6); + return -EINVAL; + } + + return 0; +} + static int virtnet_probe(struct virtio_device *vdev) { int i, err; @@ -1680,6 +1769,10 @@ static int virtnet_probe(struct virtio_device *vdev) struct virtnet_info *vi; u16 max_queue_pairs; + err = virtnet_check_features(vdev); + if (err) + return -EINVAL; + /* Find if host supports multiqueue virtio_net device */ err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ, struct virtio_net_config, -- 1.9.1 -- 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/