Re: [PATCH 08/15] ipv4: Kill routes during PMTU/redirect updates.

[Joe Perches <joe@perches.com>]

On Wed, 2012-07-18 at 11:23 -0700, David Miller wrote:
> Mark them obsolete so there will be a re-lookup to fetch the
> FIB nexthop exception info.
[]
> diff --git a/net/ipv4/route.c b/net/ipv4/route.c
[]
> @@ -716,8 +717,8 @@ static void __ip_do_redirect(struct rtable *rt, struct sk_buff *skb, struct flow
>  					fnhe->fnhe_gw = new_gw;
>  				spin_unlock_bh(&fnhe_lock);
>  			}
> -			rt->rt_gateway = new_gw;
> -			rt->rt_flags |= RTCF_REDIRECTED;
> +			if (kill_route)
> +				rt->dst.obsolete = -2;

Perhaps -2 should be a #define?

Perhaps struct dst_entry.obsolete could be a char instead of
a short and a pad byte could added for some future use.

Maybe:

 include/net/dst.h |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/include/net/dst.h b/include/net/dst.h
index 5161046..6c40490 100644
--- a/include/net/dst.h
+++ b/include/net/dst.h
@@ -65,7 +65,8 @@ struct dst_entry {
 	unsigned short		pending_confirm;
 
 	short			error;
-	short			obsolete;
+	char			obsolete;
+	char			__pad3;
 	unsigned short		header_len;	/* more space at head required */
 	unsigned short		trailer_len;	/* space to reserve at tail */
 #ifdef CONFIG_IP_ROUTE_CLASSID