Re: [PATCH] net/bonding: strengthen the judgment of lacp packets

On 18/09/2017 1:50 PM, zengganghui wrote:

All mbuf packets have been init to zero when pktmbuf pool create. So judgment this flag is safe, whether or not support VLAN stripping.

Ok, but is there any need to check the ol_flags for PKT_RX_VLAN_PKT or 
check the vlan_tci at all. I haven't come across anything in the 
specification which allows LACP links to be formed on top of VLANs but I 
may be missing something? So if the ethertype is not ETHER_TYPE_SLOW it 
is irrelevant whether the packet has a VLAN tag or not.

Also on the basis that you could have LAG groups on top of VLANs, if the 
NIC doesn't support VLAN stripping/insertion then we would miss all the 
ingress LACP PDU at the moment now anyway, since the ethertype would be 
VLAN and not ETHER_TYPE_SLOW, so is_lacp_packet() would always return 0, 
and we would also fail to encapsulate the LACP PDU in the correct VLAN 
on egress as that isn't supported in the bonding implementation.

BR.
Zeng Ganghui
Huawei Technologies Co., Ltd.

-----Original Message-----
From: Doherty, Declan [mailto:declan.doherty@intel.com]
Sent: Monday, September 18, 2017 8:34 PM
To: zengganghui; dev@dpdk.org
Subject: Re: [PATCH] net/bonding: strengthen the judgment of lacp packets

On 18/09/2017 12:12 PM, zengganghui wrote:

quoted

For example, when packets received from an MLX network card, the value of mbuf->vlan_tci is a random value. So that this value cannot be used to determine whether VLAN packets . We need to judgment mbuf->ol_flags first.

BR.
Zeng Ganghui
Huawei Technologies Co., Ltd.

-----Original Message-----
From: Doherty, Declan [mailto:declan.doherty@intel.com]
Sent: Monday, September 18, 2017 5:14 PM
To: zengganghui; dev@dpdk.org
Subject: Re: [PATCH] net/bonding: strengthen the judgment of lacp
packets

On 30/08/2017 4:46 AM, ZengGanghui wrote:

quoted

When the nic does not support vlan rx offload may be wrong, resulting
in lacp packets will not be processed.

Signed-off-by: ZengGanghui <redacted>
---

...

quoted

Acked-by: Declan Doherty <redacted>

Ok, I see your point. A LACP PDU can't be encapsulated in a VLAN packet anyway, as it is link local traffic. So a check for ol_flags & PKT_RX_VLAN_PKT != 0 should be sufficient, otherwise if the PKT_RX_VLAN_PKT flag is true the packet cannot be link local and therefore a LACP PDU. I think that it's safe to assume all PMDs must set this flag if VLAN stripping is enabled?