Traffic Shaping: Ingress qdisc not working in Dom0 (3.0.4-1)

Traffic Shaping: Ingress qdisc not working in Dom0 (3.0.4-1)

[Timo Benk]

Hello,

i noticed that the ingress qdisc is not working properly anymore in
3.0.4-1 (back in 3.0.2 the ingress qdisc was working for me):

Install the ingress qdisc to peth0:

# tc add qdisc dev peth0 ingress

... generate some traffic ...

# tc -s qdisc show dev peth0
qdisc pfifo_fast 0: bands 3 priomap  1 2 2 2 1 2 0 0 1 1 1 1 1 1 1 1
 Sent 324884 bytes 1749 pkt (dropped 0, overlimits 0 requeues 0)
 rate 0bit 0pps backlog 0b 0p requeues 0
qdisc ingress ffff: ----------------
 Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
^^^^^^^^^^^^^^^^^^^
 rate 0bit 0pps backlog 0b 0p requeues 0

The ingress qdisc on peth0 gets no traffic somehow.

If i stop the bridge via 'network-bridge stop', the ingress qdisc
works as expected. But as far as the bridge is created, the
ingress qdisc stops working on peth0.


Greetings,
-timo
-- 
Timo Benk - Jabber ID: fry@downtempo.de - ICQ ID: #414944731
PGP Public Key: http://m28s01.vlinux.de/timo_benk_gpg_key.asc

Re: Traffic Shaping: Ingress qdisc not working in Dom0 (3.0.4-1)

[Keir Fraser]

On 4/2/07 13:32, "Timo Benk" <timo.benk@gmx.de> wrote:

> The ingress qdisc on peth0 gets no traffic somehow.
> 
> If i stop the bridge via 'network-bridge stop', the ingress qdisc
> works as expected. But as far as the bridge is created, the
> ingress qdisc stops working on peth0.

My guess would be that this is unlikely to be a Xen-specific issue, and that
something has changed in packet delivery that causes packets picked up by a
bridge to not be checked for ingress filtering. This is fairly plausible
because bridged packets are stolen from the normal packet-reception path
quite early on, and it's very believable that changes in that area of the
code wouldn't have been tested for tc/etherbridge interactions. I've cc'ed
Herbert Xu just in case he has any ideas, since he's often aware of goings
on in the Linux networking code.

 -- Keir

Re: Traffic Shaping: Ingress qdisc not working in Dom0 - solved (3.0.4-1)

[Timo Benk]

Keir Fraser wrote:
> On 4/2/07 13:32, "Timo Benk" <timo.benk@gmx.de> wrote:
> 
>> The ingress qdisc on peth0 gets no traffic somehow.
>>
>> If i stop the bridge via 'network-bridge stop', the ingress qdisc
>> works as expected. But as far as the bridge is created, the
>> ingress qdisc stops working on peth0.
> 
> My guess would be that this is unlikely to be a Xen-specific issue, and that
> something has changed in packet delivery that causes packets picked up by a
> bridge to not be checked for ingress filtering. This is fairly plausible
> because bridged packets are stolen from the normal packet-reception path
> quite early on, and it's very believable that changes in that area of the
> code wouldn't have been tested for tc/etherbridge interactions. I've cc'ed
> Herbert Xu just in case he has any ideas, since he's often aware of goings
> on in the Linux networking code.

I found the reason :-)

there was some problem rebuilding the kernel. After i have done a 'make clean'
in the xen-kernel directory and rebuilt the whole kernel, the ingress qdisc is
working like before again.

Greetings,
-timo

-- 
Timo Benk - Jabber ID: fry@downtempo.de - ICQ ID: #414944731
PGP Public Key: http://m28s01.vlinux.de/timo_benk_gpg_key.asc