Re: 5.4 Regression in r8169 with jumbo frames - packet loss/delays

[Alan J. Wylie]

at 22:37 on Sat 30-Nov-2019 Heiner Kallweit (hkallweit1@xxxxxxxxx) wrote:

> Thanks for the report. A jumbo fix for one chip version may have
> revealed an issue with another chip version. Could you please try
> the following?

I'll do that in the morning.

> I checked the vendor driver r8168 and there's no special sequence
> to configure jumbo mode.
> 
> What would be interesting:
> Do you set the (jumbo) MTU before bringing the device up?

In the meantime here's some info: I use systemd/networkd, I'd suspect
that it does the MTU in the link, before the network.

$ for f in /etc/systemd/network/*; do echo "========== $f =========="; cat $f; done
========== /etc/systemd/network/01br0.netdev ==========
[NetDev]
Name=br0
Kind=bridge
MACAddress=90:2b:34:9d:ed:6f
========== /etc/systemd/network/02enp3s0.link ==========
[Match]
Driver=r8169

[Link]
MTUBytes=6000
========== /etc/systemd/network/02enp3s0.network ==========
[Match]
Name=enp3s0

[Network]
Bridge=br0

[Link]
MTUBytes=6000
========== /etc/systemd/network/03br0.network ==========
[Match]
Name=br0

[Link]
MTUBytes=6000

[Network]
DNS=192.168.21.1
Address=192.168.21.2/24
Gateway=192.168.21.1

Also, here's a grep of the syslog, I'm not sure how much to trust the
ordering though:

Nov 30 20:02:10 frodo kernel: Linux version 5.4.0-rc1-00312-g4ebcb113edcc (alan@frodo) (gcc version 9.2.0 (Gentoo Hardened 9.2.0-r2 p3)) #4 SMP PREEMPT Sat Nov 30 19:59:34 GMT 2019
Nov 30 20:02:10 frodo systemd-networkd[819]: br0: netdev ready
Nov 30 20:02:10 frodo systemd-networkd[819]: Enumeration completed
Nov 30 20:02:10 frodo systemd-networkd[819]: br0: rtnl: received neighbor message with invalid family, ignoring.
Nov 30 20:02:10 frodo systemd-networkd[819]: br0: IPv6 successfully enabled
Nov 30 20:02:10 frodo systemd-networkd[819]: br0: Gained carrier
Nov 30 20:02:10 frodo systemd-networkd[819]: br0: Lost carrier
Nov 30 20:02:10 frodo systemd-networkd[819]: br0: Gained IPv6LL
Nov 30 20:02:10 frodo systemd-networkd[819]: enp3s0: Gained carrier
Nov 30 20:02:10 frodo systemd-networkd[819]: enp3s0: Configured
Nov 30 20:02:10 frodo systemd-networkd[819]: br0: Gained carrier
Nov 30 20:02:10 frodo ntpd[1029]: 2019-11-30T20:02:10 ntpd[1029]: IO: Listen normally on 3 br0 192.168.21.2:123
Nov 30 20:02:10 frodo ntpd[1029]: 2019-11-30T20:02:10 ntpd[1029]: IO: Listen normally on 5 br0 [fe80::922b:34ff:fe9d:ed6f%3]:123
Nov 30 20:02:10 frodo ntpd[1029]: IO: Listen normally on 3 br0 192.168.21.2:123
Nov 30 20:02:10 frodo ntpd[1029]: IO: Listen normally on 5 br0 [fe80::922b:34ff:fe9d:ed6f%3]:123
Nov 30 20:02:10 frodo kernel: device: 'eth0': device_add
Nov 30 20:02:10 frodo kernel: PM: Adding info for No Bus:eth0
Nov 30 20:02:10 frodo kernel: r8169 0000:03:00.0 eth0: RTL8168evl/8111evl, 90:2b:34:9d:ed:6f, XID 2c9, IRQ 30
Nov 30 20:02:10 frodo kernel: r8169 0000:03:00.0 eth0: jumbo features [frames: 9200 bytes, tx checksumming: ko]
Nov 30 20:02:10 frodo kernel: r8169 0000:03:00.0 enp3s0: renamed from eth0
Nov 30 20:02:10 frodo kernel: net eth0: renaming to enp3s0
Nov 30 20:02:10 frodo kernel: device: 'br0': device_add
Nov 30 20:02:10 frodo kernel: PM: Adding info for No Bus:br0
Nov 30 20:02:10 frodo kernel: br0: port 1(enp3s0) entered blocking state
Nov 30 20:02:10 frodo kernel: br0: port 1(enp3s0) entered disabled state
Nov 30 20:02:10 frodo kernel: device enp3s0 entered promiscuous mode
Nov 30 20:02:10 frodo kernel: br0: port 1(enp3s0) entered blocking state
Nov 30 20:02:10 frodo kernel: br0: port 1(enp3s0) entered forwarding state
Nov 30 20:02:10 frodo kernel: r8169 0000:03:00.0 enp3s0: Link is Down
Nov 30 20:02:10 frodo kernel: IPv6: ADDRCONF(NETDEV_CHANGE): br0: link becomes ready
Nov 30 20:02:10 frodo kernel: br0: port 1(enp3s0) entered disabled state
Nov 30 20:02:10 frodo kernel: r8169 0000:03:00.0 enp3s0: Link is Up - 1Gbps/Full - flow control rx/tx
Nov 30 20:02:10 frodo kernel: IPv6: ADDRCONF(NETDEV_CHANGE): enp3s0: link becomes ready
Nov 30 20:02:10 frodo kernel: br0: port 1(enp3s0) entered blocking state
Nov 30 20:02:10 frodo kernel: br0: port 1(enp3s0) entered forwarding state
Nov 30 20:02:14 frodo systemd-networkd[819]: br0: Configured

-- 
Alan J. Wylie                                          https://www.wylie.me.uk/

Dance like no-one's watching. / Encrypt like everyone is.
Security is inversely proportional to convenience