On Sun, Feb 22, 2026, Ido Schimmel wrote:

Did you consider using the nexthop API [1]?

It doesn't suffer from this problem since the nexthop ID is used in the
FIB info hash computation and it does not require patching every LWT
family.

[1]
# cat lwt_hash_nhid.sh
#!/bin/bash

ip link add name dummy1 up type dummy
ip address add 192.168.1.2/24 dev dummy1

rm -f /tmp/batch.txt
for i in {1..100000}; do
        echo "nexthop add id $i encap mpls $((i+15)) via 192.168.1.1 dev dummy1"
        echo "route add 100.$((i>>16&255)).$((i>>8&255)).$((i&255))/32 nhid $i"
done > /tmp/batch.txt

time ip -batch /tmp/batch.txt
# ./lwt_hash_nhid.sh

real    0m0.467s
user    0m0.109s
sys     0m0.347s

Hi, Ido Schimmel.

Thanks for the feedback!

The nexthop ID approach works well. I agree that using nexthop ID in
userspace is a better way than writing patches for each type of LWT.

Please consider this patch withdrawn.