> -----Original Message----- > From: Simon K?gstr?m [mailto:simon.kagstrom at netinsight.net] > Sent: Tuesday, June 2, 2015 1:44 PM > To: Zhang, Helin; dev at dpdk.org > Subject: Re: [dpdk-dev] [PATCH / RFC] kni: Add set_rx_mode callback to handle > multicast groups > > On 2015-06-02 05:44, Zhang, Helin wrote: > >> -----Original Message----- > >> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Simon Kagstrom > >> Sent: Thursday, May 7, 2015 9:18 PM > >> To: dev at dpdk.org > >> Subject: [dpdk-dev] [PATCH / RFC] kni: Add set_rx_mode callback to > >> handle multicast groups > >> > >> This is needed to add / remove interfaces in multicast groups via the ip > >> tool. > > Could you help to explain with more details of why it is needed? > > We did some (very basic) tests with IGMP, which involves adding multicast > addresses to ETH interfaces. This is done via the ip tool, an example can be > found > on e.g., > > > http://superuser.com/questions/324824/linux-built-in-or-open-source-program- > to-join-multicast-group > > and this will fail on KNI interfaces with the current code because of an > unimplemented ioctl (as Stephen Hemminger said earlier). The patch simply adds > an empty callback so that the ioctl succeeds, and this is the same thing as > the > Linux tap interface does (so I think it should be enough for KNI as well). Yes, the root cause "null ioctl causes the failure" should be added in the commit log for future reference by others. I am OK for the reason, please add the details to the commit logs.
Thanks, Helin > > > If you want, I can update the patch with a bit more description (something > like > the above). > > // Simon