Re: [PATCH v3 2/2] net: tulip: add .can_recieve routine

[Jason Wang <jasowang@redhat.com>]

On 2020/3/17 下午6:49, P J P wrote:
> +-- On Tue, 17 Mar 2020, Jason Wang wrote --+
> | > +-- On Fri, 6 Mar 2020, Stefan Hajnoczi wrote --+
> | > | > +static int
> | > | > +tulip_can_receive(NetClientState *nc)
> | > | > +{
> | > | > +    TULIPState *s = qemu_get_nic_opaque(nc);
> | > | > +
> | > | > +    if (s->rx_frame_len || tulip_rx_stopped(s)) {
> | > | > +        return false;
> | > | > +    }
> |
> | Btw, what's the point of checking rx_frame_len here?
>
> tulip_can_recive() is called from tulip_receive(). IIUC non zero(0)
> 'rx_frame_len' hints that s->rs_frame[] buffer still has unread data bytes and
> it can not receive new bytes. The check was earlier in tulip_receive().


Right, so need to make sure qemu_flush_ququed_packets() was called when 
rx_frame_len is zero.

Thanks



>
> Thank you.
> --
> Prasad J Pandit / Red Hat Product Security Team
> 8685 545E B54C 486B C6EB 271E E285 8B5A F050 DE8D