From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Wang Subject: Re: [PATCH 2/2] virtio-net: fix buggy features advertised by host Date: Thu, 13 Nov 2014 14:45:54 +0800 Message-ID: <546453A2.8050304@redhat.com> References: <1415857974-23326-1-git-send-email-jasowang@redhat.com> <1415857974-23326-2-git-send-email-jasowang@redhat.com> <54644A4E.7000902@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, virtualization@lists.linux-foundation.org, mst@redhat.com To: gaowanlong@cn.fujitsu.com, linux-kernel@vger.kernel.org Return-path: In-Reply-To: <54644A4E.7000902@cn.fujitsu.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org List-Id: netdev.vger.kernel.org On 11/13/2014 02:06 PM, Wanlong Gao wrote: > On 11/13/2014 01:52 PM, Jason Wang wrote: >> This patch tries to detect the possible buggy features advertised by host >> and fix them. One example is booting virtio-net with only ctrl_vq disabled, >> qemu may still advertise many features which depends on it. This will >> trigger several BUG()s in virtnet_send_command(). >> >> This patch utilizes the fix_features() method, and disables all features that >> depends on ctrl_vq if it was not advertised. >> >> This fixes the crash when booting with ctrl_vq=off. >> >> Cc: Rusty Russell >> Cc: Michael S. Tsirkin >> Signed-off-by: Jason Wang >> --- >> Changes from V1: >> - fix the cut-and-paste error >> --- >> drivers/net/virtio_net.c | 35 +++++++++++++++++++++++++++++++++++ >> 1 file changed, 35 insertions(+) >> >> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c >> index ec2a8b4..6ce125e 100644 >> --- a/drivers/net/virtio_net.c >> +++ b/drivers/net/virtio_net.c >> @@ -1948,6 +1948,40 @@ static int virtnet_restore(struct virtio_device *vdev) >> } >> #endif >> >> +static void virtnet_fix_features(struct virtio_device *dev) >> +{ >> + if (!virtio_has_feature(dev, VIRTIO_NET_F_CTRL_VQ)) { >> + if (virtio_has_feature(dev, VIRTIO_NET_F_CTRL_RX)) { >> + pr_warning("Disable VIRTIO_NET_F_CTRL_RX since host " >> + "does not advertise VIRTIO_NET_F_CTRL_VQ"); >> + virtio_disable_feature(dev, VIRTIO_NET_F_CTRL_RX); >> + } >> + if (virtio_has_feature(dev, VIRTIO_NET_F_CTRL_VLAN)) { >> + pr_warning("Disable VIRTIO_NET_F_CTRL_VLAN since host " >> + "does not advertise VIRTIO_NET_F_CTRL_VQ"); >> + virtio_disable_feature(dev, VIRTIO_NET_F_CTRL_VLAN); >> + } >> + if (virtio_has_feature(dev, VIRTIO_NET_F_GUEST_ANNOUNCE)) { >> + pr_warning("Disable VIRTIO_NET_F_GUEST_ANNOUNCE since " >> + "host does not advertise " >> + "VIRTIO_NET_F_CTRL_VQ"); >> + virtio_disable_feature(dev, >> + VIRTIO_NET_F_GUEST_ANNOUNCE); >> + } >> + if (virtio_has_feature(dev, VIRTIO_NET_F_MQ)) { >> + pr_warning("Disable VIRTIO_NET_F_MQ since host " >> + "does not advertise VIRTIO_NET_F_CTRL_VQ"); >> + virtio_disable_feature(dev, VIRTIO_NET_F_MQ); >> + } >> + if (virtio_has_feature(dev, VIRTIO_NET_F_CTRL_MAC_ADDR)) { >> + pr_warning("Disable VIRTIO_NET_F_CTRL_MAC_ADDR since " >> + "host does not advertise " >> + "VIRTIO_NET_F_CTRL_VQ"); >> + virtio_disable_feature(dev, VIRTIO_NET_F_CTRL_MAC_ADDR); >> + } > > Can we use a feature array and check with one loop? The current check looks so dup? > > > Thanks, > Wanlong Gao > Yes for sure. I will wait a little bit for the maintainers comment and do it in next version. Thanks