Re: flow rule to drop all the packets

[Filip Janiszewski <contact@filipjaniszewski.com>]

This issue exists only for Intel E810 NICs, using the Mellanox cards
I've in the lab a rule like this:

.
flow create 0 ingress pattern eth type spec 0x0000 type mask 0x0000 /
end actions drop / end
.

Will happily work and drop every packet, then I can create a new rule
with higher priority to capture just the packets I'm interested.

So I guess if there's some Intel guy they can have a look on why nothing
like this is supported in the DPDK ICE driver (or perhaps the nic?)

Thanks

Il 11/30/21 4:24 PM, Filip Janiszewski ha scritto:
> Hi,
> 
> Is there a way to create a flow rule that drops all the eth packets?
> I've attempted to setup a flow rule that match any ether type but it's
> never validated, for example a rule like:
> 
> .
>     rte_flow_item_eth eth_spec{};
>     eth_spec.hdr.ether_type = RTE_BE16(0x8100);
>     rte_flow_item_eth eth_mask{};
>     eth_mask.hdr.ether_type = 0xFFFF;
> .
> 
> Should match every packet with ether type 0x8100, so I would assume that
> setting ether_type for the mask to 0x0000 would trigger the card to
> match everything regardless of the spec value, but it doesn't run
> ("Invalid input set" is the complain).
> 
> Also with testpmd I'm failing to make it work and the documentation on
> this entire rte flow is pretty poor..
> 
> So, how do I configure a rule that drops all*? My use case would be that
> I need to filter a link that is getting a lot of stuff, I'll drop all
> but just certain flows that are relevant to me (using an higher priority
> rule)..
> 
> Perhaps there's a way to configure an ingress rule that automatically
> drops everything which is not matching the rule?
> 
> As a side note, I can't just disable RSS, spit all to queue 0 like it
> was a void bucket (dropping/releasing) and then setting up rules for the
> packets I need so that they get enqueue to some other queue, because:
> 
> 1) I'll waste a cpu just for dropping packets
> 2) I'll probably get my stat reports full of imiss/errors since the link
> is 100G and that poor queue is going to be getting tons of packets
> 
> Thanks
> 
> 
> * I found this command:
> 
> .
> testpmd> set all queues drop 0 on
> function not implemented
> .
> 
> But, it doesn't work.
> 

-- 
BR, Filip
+48 666 369 823