Flow offload regression with 4.19 kernel
Username: MOZGIII
Origin: https://bugs.openwrt.org/index.php?do=details&task_id=2389
Device: Archer C7 v2
OpenWrt SNAPSHOT, r10451-653e05d2 no extra packages
When I set flow_offloading 1 at /etc/config/firewall, I expect the offload to work and connection speed to go up from 300 Mbps to about 700-800 Mbps at least. However, it drops to 100 Mbps instead. I tried with flow_offloading_hw 0 and 1 and it seems to irrelevant - which is ok since Archer C7 v2 isn’t supposed to have HW offload support at this point.
I did a custom build with 4.14 kernel and it works as expected, so the problem must be with the new 4.19 kernel.
Either the patches weren’t ported properly, or something’s wrong with the kernel itself. I expected there to be already some kind of evidence suggesting the issue was with updated kernel itself, and not the patches, but I couldn’t find any reports so far, so I’d bet something’s wrong with how the patches were ported.
Some additional info from the 4.19 kernel system:
root@router:~# lsmod | grep -i flow
nf_conntrack 71817 12 xt_NETMAP,ipt_MASQUERADE,xt_state,xt_nat,xt_conntrack,xt_REDIRECT,xt_CT,nf_nat_ipv4,nf_nat,nf_flow_table,nf_conntrack_rtcache,nf_conntrack_netlink
nf_flow_table 14399 2 xt_FLOWOFFLOAD,nf_flow_table_hw
nf_flow_table_hw 2192 1
x_tables 15391 26 xt_NETMAP,ipt_MASQUERADE,xt_state,xt_nat,xt_conntrack,xt_REDIRECT,xt_FLOWOFFLOAD,xt_CT,ipt_REJECT,xt_time,xt_tcpudp,xt_multiport,xt_mark,xt_mac,xt_limit,xt_comment,xt_TCPMSS,xt_LOG,iptable_mangle,iptable_filter,ip_tables,xt_set,ip6table_mangle,ip6table_filter,ip6_tables,ip6t_REJECT
xt_FLOWOFFLOAD 2832 2
root@router:~# iptables -L | grep -i off
FLOWOFFLOAD all – anywhere anywhere /* !fw3: Traffic offloading */ ctstate RELATED,ESTABLISHED FLOWOFFLOAD