On 8/27/19 11:08 AM, Yi Wang wrote:
> From: Cheng Lin <cheng.lin...@zte.com.cn>
>
> Originally, Router Reachability Probing require a neighbour entry
> existed. Commit 2152caea7196 ("ipv6: Do not depend on rt->n in
> rt6_probe().") removed the requirement for a neighbour entry. And
> commit f547fac624be ("ipv6: rate-limit probes for neighbourless
> routes") adds rate-limiting for neighbourless routes.
>
> And, the Neighbor Discovery for IP version 6 (IPv6)(rfc4861) says,
> "
> 7.2.5. Receipt of Neighbor Advertisements
>
> When a valid Neighbor Advertisement is received (either solicited or
> unsolicited), the Neighbor Cache is searched for the target's entry.
> If no entry exists, the advertisement SHOULD be silently discarded.
> There is no need to create an entry if none exists, since the
> recipient has apparently not initiated any communication with the
> target.
> ".
>
> In rt6_probe(), just a Neighbor Solicitation message are transmited.
> When receiving a Neighbor Advertisement, the node does nothing in a
> Neighborless condition.
>
> Not sure it's needed to create a neighbor entry in Router
> Reachability Probing. And the Original way may be the right way.
>
> This patch recover the requirement for a neighbour entry.
>
> Signed-off-by: Cheng Lin <cheng.lin...@zte.com.cn>
> ---
> include/net/ip6_fib.h | 5 -----
> net/ipv6/route.c | 5 +----
> 2 files changed, 1 insertion(+), 9 deletions(-)
>
> diff --git a/include/net/ip6_fib.h b/include/net/ip6_fib.h
> index 4b5656c..8c2e022 100644
> --- a/include/net/ip6_fib.h
> +++ b/include/net/ip6_fib.h
> @@ -124,11 +124,6 @@ struct rt6_exception {
>
> struct fib6_nh {
> struct fib_nh_common nh_common;
> -
> -#ifdef CONFIG_IPV6_ROUTER_PREF
> - unsigned long last_probe;
> -#endif
> -
> struct rt6_info * __percpu *rt6i_pcpu;
> struct rt6_exception_bucket __rcu *rt6i_exception_bucket;
> };
> diff --git a/net/ipv6/route.c b/net/ipv6/route.c
> index fd059e0..c4bcffc 100644
> --- a/net/ipv6/route.c
> +++ b/net/ipv6/route.c
> @@ -639,12 +639,12 @@ static void rt6_probe(struct fib6_nh *fib6_nh)
> nh_gw = &fib6_nh->fib_nh_gw6;
> dev = fib6_nh->fib_nh_dev;
> rcu_read_lock_bh();
> - idev = __in6_dev_get(dev);
> neigh = __ipv6_neigh_lookup_noref(dev, nh_gw);
> if (neigh) {
> if (neigh->nud_state & NUD_VALID)
> goto out;
>
> + idev = __in6_dev_get(dev);
> write_lock(&neigh->lock);
> if (!(neigh->nud_state & NUD_VALID) &&
> time_after(jiffies,
> @@ -654,9 +654,6 @@ static void rt6_probe(struct fib6_nh *fib6_nh)
> __neigh_set_probe_once(neigh);
> }
> write_unlock(&neigh->lock);
> - } else if (time_after(jiffies, fib6_nh->last_probe +
> - idev->cnf.rtr_probe_interval)) {
> - work = kmalloc(sizeof(*work), GFP_ATOMIC);
> }
>
> if (work) {
>
Have you really compiled this patch ?
