LAN bridge is not working with 5.15.80 [Was: Re: [PATCH v2] mvebu: switch default kernel to 5.15]

[Stefan Kalscheuer]

Hi,

I do run a Turris Omnia with a custom build on top of 
"r21380-5429411f73" (custom changes not related to networking) without 
these issues.
Updated yesterday from a previous build with testing kernel enabled.

Configuration for "br-lan" is  static IPv4+IPv6, but only 2 switch ports 
(lan0, lan3) included.

config device
     option name 'br-lan'
     option type 'bridge'
     list ports 'lan0'
     list ports 'lan3'

config interface 'lan'
     option device 'br-lan'
     option proto 'static'
     option netmask '255.255.255.0'
     option ip6assign '64'
     option ip6ifaceid '::1'
     option ipaddr '192.168.101.1'
     option ip6hint '101'
     list dns_search 'some.local.domain'


Takes quite some time for the bridge to fully come up, but it works 
fine. No noticeable difference from 5.10.146 here. Here are the dmesg 
lines related to br-lan and corresponding ports:

[    0.000000] Booting Linux on physical CPU 0x0
[    0.000000] Linux version 5.15.80 (builder at ca2a4d37db99) 
(arm-openwrt-linux-muslgnueabi-gcc (OpenWrt GCC 11.3.0 
r21373+8-aa12a0fdd1) 11.3.0, GNU ld (GNU Binutils) 2.37) #0 SMP Fri Dec 
2 16:19:11 2022
[    0.000000] CPU: ARMv7 Processor [414fc091] revision 1 (ARMv7), 
cr=10c5387d
[    4.662164] mv88e6085 f1072004.mdio-mii:10 lan0: configuring for 
phy/gmii link mode
[    5.729250] mv88e6085 f1072004.mdio-mii:10 lan0: Link is Up - 
1Gbps/Full - flow control off
[    5.737660] IPv6: ADDRCONF(NETDEV_CHANGE): lan0: link becomes ready
[    8.935023] mv88e6085 f1072004.mdio-mii:10 lan0: Link is Down
[   22.136380] br-lan: port 1(lan0) entered blocking state
[   22.136392] br-lan: port 1(lan0) entered disabled state
[   22.724369] device lan0 entered promiscuous mode
[   23.075300] mv88e6085 f1072004.mdio-mii:10 lan3: configuring for 
phy/gmii link mode
[   23.401512] br-lan: port 2(lan3) entered blocking state
[   23.401526] br-lan: port 2(lan3) entered disabled state
[   23.476021] device lan3 entered promiscuous mode
[   25.678714] mv88e6085 f1072004.mdio-mii:10 lan0: Link is Up - 
1Gbps/Full - flow control off
[   25.678755] br-lan: port 1(lan0) entered blocking state
[   25.678764] br-lan: port 1(lan0) entered forwarding state
[   25.680974] IPv6: ADDRCONF(NETDEV_CHANGE): br-lan: link becomes ready
[   26.706086] br-lan: port 3(phy1-ap0) entered blocking state
[   26.706102] br-lan: port 3(phy1-ap0) entered disabled state
[   26.706227] device phy1-ap0 entered promiscuous mode
[   27.056950] IPv6: ADDRCONF(NETDEV_CHANGE): phy1-ap0: link becomes ready
[   27.057076] br-lan: port 3(phy1-ap0) entered blocking state
[   27.057085] br-lan: port 3(phy1-ap0) entered forwarding state
[   28.056781] br-lan: port 4(phy0-ap0) entered blocking state
[   28.056796] br-lan: port 4(phy0-ap0) entered disabled state
[   28.056928] device phy0-ap0 entered promiscuous mode
[   28.056986] br-lan: port 4(phy0-ap0) entered blocking state
[   28.056993] br-lan: port 4(phy0-ap0) entered forwarding state
[   28.064807] br-lan: port 4(phy0-ap0) entered disabled state
[   28.874784] IPv6: ADDRCONF(NETDEV_CHANGE): phy0-ap0: link becomes ready
[   28.874913] br-lan: port 4(phy0-ap0) entered blocking state
[   28.874925] br-lan: port 4(phy0-ap0) entered forwarding state


 > Could you please share with me the output from ``zcat /proc/config.gz 
| grep CONFIG_NET_DSA_MV88E6XXX``? Even though, in the config [1], it 
seems that it should be enabled, it was actually not on the device itself.

My .config does not show "CONFIG_NET_DSA_MV88E6XXX" explicitly, so 
apparently it was correctly picked up from defaults as expected.


I got a second mvebu device, Linksys WRT1900ACS, flashed for testing 
this morning with unmodified r21380-5429411f73 build on 5.15.80, also 
without networkissues.


Don't know if it helps tracking down any issues.

Cheers,
Stefan