Re: [PATCH v3 1/2] net: core: Notify on changes to dev->promiscuity.

From: Jiri Pirko
Date: Fri Aug 30 2019 - 01:39:48 EST


Fri, Aug 30, 2019 at 12:12:01AM CEST, davem@xxxxxxxxxxxxx wrote:
>From: Ido Schimmel <idosch@xxxxxxxxxx>
>Date: Thu, 29 Aug 2019 22:36:13 +0300
>
>> I fully agree that we should make it easy for users to capture offloaded
>> traffic, which is why I suggested patching libpcap. Add a flag to
>> capable netdevs that tells libpcap that in order to capture all the
>> traffic from this interface it needs to add a tc filter with a trap
>> action. That way zero familiarity with tc is required from users.
>
>Why not just make setting promisc mode on the device do this rather than
>require all of this tc indirection nonsense?

Because the "promisc mode" would gain another meaning. Now how the
driver should guess which meaning the user ment when he setted it?
filter or trap?

That is very confusing. If the flag is the way to do this, let's
introduce another flag, like IFF_TRAPPING indicating that user wants
exactly this.


>
>That's the whole point of this conversation I thought?