Re: [PATCH 2.6.36] vlan: Avoid hwaccel vlan packets when vid not used

[Michael Leun <lkml20101129@newton.leun.net>]

On Wed, 01 Dec 2010 11:55:14 +0100
Eric Dumazet <eric.dumazet@gmail.com> wrote:

> Le mercredi 01 décembre 2010 à 11:17 +0100, Michael Leun a écrit :
> 
> > Yup, from what I've tested this works (and tcpdump sees broadcast
> > packets even for vlans not configured at the moment including vlan
> > tag
> > - yipee!).
> >

This was tested on machine with
root@tp_z61m:~/src/tcpdump-4.1.1# lspci|grep Eth
02:00.0 Ethernet controller: Broadcom Corporation NetXtreme BCM5752M Gigabit Ethernet PCI Express (rev 02)

There it works as I said.

But on

hpdl320g5:/home/ml # lspci | grep Eth
03:04.0 Ethernet controller: Broadcom Corporation NetXtreme BCM5714 Gigabit Ethernet (rev a3)
03:04.1 Ethernet controller: Broadcom Corporation NetXtreme BCM5714 Gigabit Ethernet (rev a3)

the good message is that it also does not crash, but with tcpdump I see
vlan tags when no vlan devices configured on the respective eth, if so
I do not see tags anymore vlan tags on the trunk interface.

hpdl320g5:/home/ml # ifconfig -a
[...]
eth1      Link encap:Ethernet  Hardware Adresse xx:xx:xx:xx:xx:xx  
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 Sendewarteschlangenlänge:1000 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)
          Interrupt:17 
[...]

hpdl320g5:/home/ml # tcpdump -i eth1 -n -e
tcpdump: WARNING: eth1: no IPv4 address assigned
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth1, link-type EN10MB (Ethernet), capture size 96 bytes
[...]
02:45:57.597640 xx:xx:xx:xx:xx:xx > ff:ff:ff:ff:ff:ff, ethertype 802.1Q (0x8100), length 64: vlan 1505, p 0, ethertype 802.1Q, vlan 99, p 3, ethertype ARP, arp who-has 10.0.0.1 tell 10.0.0.2
02:45:57.622654 xx:xx:xx:xx:xx:xx > ff:ff:ff:ff:ff:ff, ethertype 802.1Q (0x8100), length 64: vlan 1505, p 0, ethertype 802.1Q, vlan 99, p 3, ethertype ARP, arp who-has 10.0.0.1 tell 10.0.0.2
[...]

hpdl320g5:/home/ml # vconfig add eth1 2
WARNING:  Could not open /proc/net/vlan/config.  Maybe you need to load the 8021q module, or maybe you are not using PROCFS??
Added VLAN with VID == 2 to IF -:eth1:-
hpdl320g5:/home/ml # cat /proc/net/vlan/config 
VLAN Dev name    | VLAN ID
Name-Type: VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD
eth1.2         | 2  | eth1
hpdl320g5:/home/ml # tcpdump -i eth1 -n -e
tcpdump: WARNING: eth1: no IPv4 address assigned
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth1, link-type EN10MB (Ethernet), capture size 96 bytes
[...]
02:50:18.095959 xx:xx:xx:xx:xx:xx > ff:ff:ff:ff:ff:ff, ethertype 802.1Q (0x8100), length 60: vlan 99, p 3, ethertype ARP, arp who-has 10.0.0.1 tell 10.0.0.2
02:50:18.120989 xx:xx:xx:xx:xx:xx > ff:ff:ff:ff:ff:ff, ethertype 802.1Q (0x8100), length 60: vlan 99, p 3, ethertype ARP, arp who-has 10.0.0.1 tell 10.0.0.2
[...]

The same packages we saw double vlan tagged a few minutes ago now appear single vlan tagged (and of course, other packets that were shown single vlan tagged before are now shown without vlan tag / eth type 0x0800).


On the other machine:

root@tp_z61m:~# cat /proc/net/vlan/config 
VLAN Dev name    | VLAN ID
Name-Type: VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD
eth0.741       | 741  | eth0
eth0.2         | 2  | eth0
root@tp_z61m:~/src/tcpdump-4.1.1# ./tcpdump -i eth0 -n -e not port 22
tcpdump: WARNING: eth0: no IPv4 address assigned
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes
03:06:51.859016 xx:xx:xx:xx:xx:xx > ff:ff:ff:ff:ff:ff, ethertype 802.1Q (0x8100), length 64: vlan 1505, p 0, ethertype 802.1Q, vlan 99, p 3, ethertype ARP, Request who-has 10.0.0.1 tell 10.0.0.2, length 42
03:06:51.883956 xx:xx:xx:xx:xx:xx > ff:ff:ff:ff:ff:ff, ethertype 802.1Q (0x8100), length 64: vlan 1505, p 0, ethertype 802.1Q, vlan 99, p 3, ethertype ARP, Request who-has 10.0.0.1 tell 10.0.0.2, length 42



[...]
> Here is the revised patch again then for stable team, via David Miller
> agreement.
[...]

-- 
MfG,

Michael Leun