Re: [PATCH RE-SUBMIT 2/2] net/pch_gbe: supports eg20t ptp clock

[Richard Cochran <richardcochran@gmail.com>]

On Mon, Mar 12, 2012 at 09:35:44AM +0900, Takahiro Shimizu wrote:
> Hello Richard,
> 
> Thank you for the comment.
> 
> > +     if ((sk_run_filter(skb, ptp_filter) != PTP_CLASS_V2_IPV4) &&
> > > +             (sk_run_filter(skb, ptp_filter) != PTP_CLASS_V1_IPV4)) {
> >
> > No, just run the filter once and test the result twice.
> >
> > Also, doesn't the timestamping unit work with IPv6 and L2?  If so,
> > don't restrict the driver to IPv4.
> >
> >
> According to the EG20T spec, it support IPv6 too. But I did not any test
> about IPv6 now.
> Do you mean I don't restrict anything here?

No, what I mean is that you only accept PTP_CLASS_V1_IPV4 or
PTP_CLASS_V2_IPV4. You should accept any packet type supported by the
hardware.

If someone tries to use your driver with PTPv2 over UDPv6, for
example, then the filter will return PTP_CLASS_V2_IPV6, and the match
will fail. It will also fail for PTPv2 L2 and PTPv2 L2/VLAN.

It does not make sense to me to limit the driver in this way.

Richard