5.10-stable review patch. If anyone has any objections, please let me know.
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From: Sriram Yagnaraman sriram.yagnaraman@est.tech
[ Upstream commit 6ac66cb03ae306c2e288a9be18226310529f5b25 ]
Route hints when the nexthop is part of a multipath group causes packets in the same receive batch to be sent to the same nexthop irrespective of the multipath hash of the packet. So, do not extract route hint for packets whose destination is part of a multipath group.
A new SKB flag IPSKB_MULTIPATH is introduced for this purpose, set the flag when route is looked up in ip_mkroute_input() and use it in ip_extract_route_hint() to check for the existence of the flag.
Fixes: 02b24941619f ("ipv4: use dst hint for ipv4 list receive") Signed-off-by: Sriram Yagnaraman sriram.yagnaraman@est.tech Reviewed-by: Ido Schimmel idosch@nvidia.com Reviewed-by: David Ahern dsahern@kernel.org Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- include/net/ip.h | 1 + net/ipv4/ip_input.c | 3 ++- net/ipv4/route.c | 1 + 3 files changed, 4 insertions(+), 1 deletion(-)
diff --git a/include/net/ip.h b/include/net/ip.h index 8d1173577fb5c..9be2efe00f2c0 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -56,6 +56,7 @@ struct inet_skb_parm { #define IPSKB_FRAG_PMTU BIT(6) #define IPSKB_L3SLAVE BIT(7) #define IPSKB_NOPOLICY BIT(8) +#define IPSKB_MULTIPATH BIT(9)
u16 frag_max_size; }; diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c index eccd7897e7aa6..372579686162b 100644 --- a/net/ipv4/ip_input.c +++ b/net/ipv4/ip_input.c @@ -566,7 +566,8 @@ static void ip_sublist_rcv_finish(struct list_head *head) static struct sk_buff *ip_extract_route_hint(const struct net *net, struct sk_buff *skb, int rt_type) { - if (fib4_has_custom_rules(net) || rt_type == RTN_BROADCAST) + if (fib4_has_custom_rules(net) || rt_type == RTN_BROADCAST || + IPCB(skb)->flags & IPSKB_MULTIPATH) return NULL;
return skb; diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 374647693d7ac..3ddeb4fc0d08a 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -2066,6 +2066,7 @@ static int ip_mkroute_input(struct sk_buff *skb, int h = fib_multipath_hash(res->fi->fib_net, NULL, skb, hkeys);
fib_select_multipath(res, h); + IPCB(skb)->flags |= IPSKB_MULTIPATH; } #endif