Re: B53 DSA switch problem on Banana Pi-R1 on Fedora 26 - systemd-networkd problem

From: Gerhard Wiesinger
Date: Mon May 28 2018 - 01:32:23 EST


On 27.05.2018 22:31, Florian Fainelli wrote:
Le 05/27/18 Ã 12:01, Gerhard Wiesinger a ÃcritÂ:
On 24.05.2018 08:22, Gerhard Wiesinger wrote:
On 24.05.2018 07:29, Gerhard Wiesinger wrote:
After some analysis with Florian (thnx) we found out that the current
implementation is broken:

https://patchwork.ozlabs.org/patch/836538/
https://github.com/torvalds/linux/commit/c499696e7901bda18385ac723b7bd27c3a4af624#diff-a2b6f8d89e18de600e873ac3ac43fa1d


Florians comment:

c499696e7901bda18385ac723b7bd27c3a4af624 ("net: dsa: b53: Stop using
dev->cpu_port incorrectly") since it would result in no longer setting
the CPU port as tagged for a specific VLAN. Easiest way for you right
now is to just revert it, but this needs some more thoughts for a proper
upstream change. I will think about it some more.
Can confirm 4.14.18-200.fc26.armv7hl works, 4.15.x should be broken.

# Kernel 4.14.x ok
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/log/drivers/net/dsa/b53?h=v4.14.43

# Kernel 4.15.x should be NOT ok
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/log/drivers/net/dsa/b53?h=v4.15.18

Kernel 4.14.18-300.fc27.armv7hl works well so far, even with FC28
update. Florian send me a patch to try for 4.16.x
So does my patch make 4.16 work correctly for you now? If so, can I just
submit it and copy you?

I got the commands below to work with manual script commands.
Afterwards I wrote systemd-networkd config where I've a strage problem
when IPv6 sends a multicast broadcast from another machine to the bridge
this will be sent back via the network interface, but with the source
MAC of the bridge of the other machine. dmesg from the other machine:
[117768.330444] br0: received packet on lan0 with own address as source
address (addr:a0:36:9f:ab:cd:ef, vlan:0)
[117768.334887] br0: received packet on lan0 with own address as source
address (addr:a0:36:9f:ab:cd:ef, vlan:0)
[117768.339281] br0: received packet on lan0 with own address as source
address (addr:a0:36:9f:ab:cd:ef, vlan:0)

And: If I just enter this command after e.g. a systemd-network restart
everything is fine forever:
# Not OK (dmesg message above is triggered on a remote computer, whole
switching network gets unstable, ssh terminals close, packet loss, etc.)
systemctl restart systemd-networkd
# OK again when this command is entered
bridge vlan add dev wan vid 102 pvid untagged

brctl show, ip link, bridge vlan, bridge link commands, etc. look all
the same, also /sys/class/net/br0/bridge, /sys/class/net/br1/bridge
settings

Systemd config correct?
Any ideas?
You should not have eth0.101 and eth0.102 to be enslaved in a bridge at
all, this is what is causing the bridge to be confused. Remember what I
wrote to you before, with the current b53 driver that does not have any
tagging enabled the lanX interfaces and brX interfaces are only used for
control and should not be used for passing any data. The only network
device that will be passing data is eth0, which is why we need to set-up
VLAN interfaces to pop/push the VLAN id accordingly.

I have no idea why manual vs. systemd does not work but you can most
certainly troubleshoot that by comparing the bridge/ip outputs.

So is that then the correct structure?

br1
- lan1 (with VID 101)
- lan2 (with VID 101)
- lan3 (with VID 101)
- lan4 (with VID 101)

brlan
- eth0.101
- wlan0 (currently not active, could be optimized without bridge but for future comfort)

br2
- wan (with VID 102) (could be optimized without bridge but for future comfort)
- future1

brwan
- eth0.102 (could be optimized without bridge but for future comfort)
- future2

Ad systemd vs. manual config: As I said I didn't find any difference in the bridge/ip outputs. As they are broken (see other message) maybe something else is broken, too.

Thnx.

Ciao,
Gerhard