Hi jason
On Mon, Oct 26, 2020 at 11:20 AM Jason Wang <jasow...@redhat.com> wrote:
>
> On 2020/10/26 上午10:43, Jason Wang wrote:
> >
> > On 2020/10/23 下午5:15, Cindy Lu wrote:
> >> Sometime vdpa get an all 0 mac address from the hardware, this will
> >> cause the traffic down
> >> So we add the check for this part.
> >> if we get an 0 mac address we will use the default mac address instead
> >>
> >> Signed-off-by: Cindy Lu <l...@redhat.com>
> >> ---
> >> hw/net/virtio-net.c | 7 ++++++-
> >> 1 file changed, 6 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
> >> index 9179013ac4..f1648fc47d 100644
> >> --- a/hw/net/virtio-net.c
> >> +++ b/hw/net/virtio-net.c
> >> @@ -126,6 +126,7 @@ static void virtio_net_get_config(VirtIODevice
> >> *vdev, uint8_t *config)
> >> VirtIONet *n = VIRTIO_NET(vdev);
> >> struct virtio_net_config netcfg;
> >> NetClientState *nc = qemu_get_queue(n->nic);
> >> + static const MACAddr zero = { .a = { 0, 0, 0, 0, 0, 0 } };
> >> int ret = 0;
> >> memset(&netcfg, 0 , sizeof(struct virtio_net_config));
> >> @@ -151,7 +152,11 @@ static void virtio_net_get_config(VirtIODevice
> >> *vdev, uint8_t *config)
> >> ret = vhost_net_get_config(get_vhost_net(nc->peer),
> >> (uint8_t *)&netcfg,
> >> n->config_size);
> >> if (ret != -1) {
> >> - memcpy(config, &netcfg, n->config_size);
> >> + if (memcmp(&netcfg.mac, &zero, sizeof(zero)) != 0) {
> >> + memcpy(config, &netcfg, n->config_size);
> >> + } else {
> >> + error_report("Get an all zero mac address from
> >> hardware");
> >> + }
> >> }
> >> }
> >> }
> >
> >
> > Applied.
> >
> > Thanks
> >
> >
>
> Speak too fast. Some questions:
>
> 1) Any reason that you do such check or get_config() instead of doing it
> once in device initalization
>
get_config() was called before the device realized. If we check in the
device initalization, the mac address is already overwritten to 0 and
we lost the default mac address
Also for my understanding. the mac address read from hardware should never
been 0, so we need to check it every time we got it, Just in case it will
change to 0 and overwrite the mac address while the qemu running or some
other case
> 2) the indentation looks wrong
>
sure will fix this
> 3) There's no need for an error here since we can workaround it
sure, I will change it to log
>
>
> Thanks
>
>
