Commit c97426ec649d for kernel

commit c97426ec649d99596d8969e1a052c16b14b7b485
Author: Daehyeon Ko <4ncienth@gmail.com>
Date:   Thu Oct 8 14:29:23 2026 +0900

    ipv6: do not warn on route notification size race

    fib6_info_hw_flags_set() sizes the skb with rt6_nlmsg_size() and later
    fills it with rt6_fill_node().  With nexthop compatibility mode enabled,
    a concurrent replacement can grow the group between these independent
    snapshots.  rt6_fill_node() can then legitimately return -EMSGSIZE, so
    the warning does not prove a sizing bug.

    Remove the warning.  The existing error path still frees the skb and
    reports the error to listeners.

    Fixes: 907eea486888 ("net: ipv6: Emit notification when fib hardware flags are changed")
    Reported-by: Ido Schimmel <idosch@nvidia.com>
    Link: https://lore.kernel.org/netdev/20261007114003.GA1011260@shredder/
    Suggested-by: Ido Schimmel <idosch@nvidia.com>
    Cc: stable@vger.kernel.org
    Signed-off-by: Daehyeon Ko <4ncienth@gmail.com>
    Link: https://patch.msgid.link/4012604727e5ba80b69ccd4d08796511397ddaef.1791423190.git.4ncienth@gmail.com
    Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 153ce16628c1..a5e955e56e79 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -6509,8 +6509,6 @@ void fib6_info_hw_flags_set(struct net *net, struct fib6_info *f6i,
 	err = rt6_fill_node(net, skb, f6i, NULL, NULL, NULL, 0, RTM_NEWROUTE, 0,
 			    0, 0, RT_DEL_REASON_UNSPEC);
 	if (err < 0) {
-		/* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
-		WARN_ON(err == -EMSGSIZE);
 		kfree_skb(skb);
 		goto errout;
 	}