On Mon, Oct 10, 2016 at 10:49 PM, Ido Schimmel <ido...@idosch.org> wrote:
> Hi,
>
> On Mon, Oct 10, 2016 at 08:15:39PM +0900, Ryota Ozaki wrote:
>> Section "Flooding L2 domain" says, to avoid duplicated flooding, if
>> skb->offload_fwd_mark is matched with dev->skb_mark, the kernel will
>> drop the packet. However, the relevant code in __dev_queue_xmit
>> compares skb->offload_fwd_mark with dev->offload_fwd_mark, not
>> dev->skb_mark. I guess the text is wrong.
>>
>> Signed-off-by: Ryota Ozaki <ozaki.ry...@gmail.com>
>> ---
>> Documentation/networking/switchdev.txt | 4 ++--
>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/Documentation/networking/switchdev.txt
>> b/Documentation/networking/switchdev.txt
>> index 31c3911..d4124a0 100644
>> --- a/Documentation/networking/switchdev.txt
>> +++ b/Documentation/networking/switchdev.txt
>> @@ -286,8 +286,8 @@ otherwise there will be duplicate packets on the wire.
>> To avoid duplicate packets, the device/driver should mark a packet as
>> already
>> forwarded using skb->offload_fwd_mark. The same mark is set on the device
>> ports in the domain using dev->offload_fwd_mark. If the
>> skb->offload_fwd_mark
>> -is non-zero and matches the forwarding egress port's dev->skb_mark, the
>> kernel
>> -will drop the skb right before transmit on the egress port, with the
>> +is non-zero and matches the forwarding egress port's dev->offload_fwd_mark,
>> +the kernel will drop the skb right before transmit on the egress port, with
>> the
>
> I think your tree isn't up to date. The flooding mechanism (and this
> document) were modified in commit 6bc506b4fb06 ("bridge: switchdev: Add
> forward mark support for stacked devices")
> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=6bc506b4fb065eac3d89ca1ce37082e174493d9e
Oh, right. I forgot to rebase my branch after the 4.9 merge period
and saw the file as of 4.8.
>
> Also, in the future, please specify to which tree (net, net-next) your
> patch should go. See:
> https://www.kernel.org/doc/Documentation/networking/netdev-FAQ.txt
> (under "How do I indicate which tree (net vs. net-next) my patch
> should be in?").
Thanks for the pointer. I'll follow the rule next time.
Thanks,
ozaki-r
>
> Thanks!
>
>> understanding that the device already forwarded the packet on same egress
>> port.
>> The driver can use switchdev_port_fwd_mark_set() to set a globally unique
>> mark
>> for port's dev->offload_fwd_mark, based on the port's parent ID (switch ID)
>> and
>> --
>> 2.7.4
>>
