On Wed, Jan 16, 2013 at 01:23:26PM +0800, Amos Kong wrote: > On Thu, Jan 10, 2013 at 10:57:05PM +0800, Jason Wang wrote: > > On 01/10/2013 10:45 PM, akong@xxxxxxxxxx wrote: > > > From: Amos Kong <akong@xxxxxxxxxx> > > > > > > Currently we write MAC address to pci config space byte by byte, > > > this means that we have an intermediate step where mac is wrong. > > > This patch introduced a new control command to set MAC address > > > in one time. > > > > > > VIRTIO_NET_F_CTRL_MAC_ADDR is a new feature bit for compatibility. > > > > > > Signed-off-by: Amos Kong <akong@xxxxxxxxxx> > > > --- > > > drivers/net/virtio_net.c | 16 +++++++++++++++- > > > include/uapi/linux/virtio_net.h | 8 +++++++- > > > 2 files changed, 22 insertions(+), 2 deletions(-) > > > > > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > > > index 395ab4f..ff22bcd 100644 > > > --- a/drivers/net/virtio_net.c > > > +++ b/drivers/net/virtio_net.c > > > @@ -803,13 +803,26 @@ static int virtnet_set_mac_address(struct net_device *dev, void *p) > > > struct virtio_device *vdev = vi->vdev; > > > int ret; > > > > > > + struct scatterlist sg; > > > + > > > ret = eth_mac_addr(dev, p); > > > if (ret) > > > return ret; > > > > > > - if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) > > > + if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) { > > > + /* Set MAC address by sending vq command */ > > > + sg_init_one(&sg, dev->dev_addr, dev->addr_len); > > > + virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC, > > > + VIRTIO_NET_CTRL_MAC_ADDR_SET, > > > + &sg, 1, 0); > > > + return 0; > > > + } > > > + > > > > Better to check the return of virtnet_send_command() and give a warn > > like other command. Btw, need we fail back to try the old way then? > > Yes, it's necessary to check the return value of > virtnet_send_command(). > > In fail case, I like to return -EINVAL to userspace, because we don't > only want to set mac successfully, we also want to resolve the > addr inconsistent issue by this feature (vq cmd). It's really a device error but I guess we can. We probably should print a warning too. -- MST -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html