Subject: Re: [PATCH for kernel 3.4.x 1/1] net: neighbour: Add mcast_resolicit to configure the number of multicast resolicitations in PROBE state

From: YOSHIFUJI Hideaki <[email-masked]>
Date: Tue, 24 Mar 2015 19:35:38 +0900

Hi.

Zhu Yanjun wrote:

> We send unicast neighbor (ARP or NDP) solicitations ucast_probes
> times in PROBE state.  Zhu Yanjun reported that some implementation
> does not reply against them and the entry will become FAILED, which
> is undesirable.
> 
> We had been dealt with such nodes by sending multicast probes mcast_
> solicit times after unicast probes in PROBE state.  In 2003, I made

I?  Or please Add the From: to change the author to me.

> a change not to send them to improve compatibility with IPv6 NDP.
> 
> Let's introduce per-protocol per-interface sysctl knob "mcast_
> reprobe" to configure the number of multicast (re)solicitation for
> reconfirmation in PROBE state.  The default is 0, since we have
> been doing so for 10+ years.
> 

You should say: 'This patch is based on commit foobar ("title") by
author...' or something here.

> Reported-by: Zhu Yanjun <[email-masked]>
> CC: Ulf Samuelsson <[email-masked]>
> Signed-off-by: YOSHIFUJI Hideaki <[email-masked]>
> Signed-off-by: YOSHIFUJI Hideaki <[email-masked]>
> [Zhu Yanjun: since kernel 3.4.x is different from mainline kernel(kernel 4.0-rcX).
> This patch is modified a lot.]
> Signed-off-by: Zhu Yanjun <[email-masked]>

> ---
>  include/linux/neighbour.h |  1 +
>  include/net/neighbour.h   |  1 +
>  net/core/neighbour.c      | 20 +++++++++++++++++---
>  3 files changed, 19 insertions(+), 3 deletions(-)
> 
> diff --git a/include/linux/neighbour.h b/include/linux/neighbour.h
> index b188f68..6945f4f 100644
> --- a/include/linux/neighbour.h
> +++ b/include/linux/neighbour.h
> @@ -112,6 +112,7 @@ enum {
>  	NDTPA_APP_PROBES,		/* u32 */
>  	NDTPA_UCAST_PROBES,		/* u32 */
>  	NDTPA_MCAST_PROBES,		/* u32 */
> +	NDTPA_MCAST_REPROBES,		/* u32 */
>  	NDTPA_ANYCAST_DELAY,		/* u64, msecs */
>  	NDTPA_PROXY_DELAY,		/* u64, msecs */
>  	NDTPA_PROXY_QLEN,		/* u32 */

No, this breaks binary compatibility.

-- 
Hideaki Yoshifuji <[email-masked]>
Technical Division, MIRACLE LINUX CORPORATION