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Date: Wed, 6 Dec 2023 08:16:05 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Ahmed Zaki <ahmed.zaki@intel.com>
Cc: <netdev@vger.kernel.org>, <davem@davemloft.net>, <edumazet@google.com>,
 <pabeni@redhat.com>, <mkubecek@suse.cz>, "Chittim, Madhu"
 <madhu.chittim@intel.com>, "Samudrala, Sridhar"
 <sridhar.samudrala@intel.com>
Subject: Re: [RFC] ethtool: raw packet filtering
Message-ID: <20231206081605.0fad0f58@kernel.org>
In-Reply-To: <459ef75b-69dc-4baa-b7e4-6393b0b358ce@intel.com>
References: <459ef75b-69dc-4baa-b7e4-6393b0b358ce@intel.com>
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On Tue, 5 Dec 2023 11:23:34 -0700 Ahmed Zaki wrote:
> We are planning to send a patch series that enables raw packet filtering 
> for ice and iavf. However, ethtool currently allows raw filtering on 
> only 8 bytes via "user-def":
> 
>    # ethtool -N eth0 flow-type user-def N [m N] action N
> 
> 
> We are seeking the community's opinion on how to extend the ntuple 
> interface to allow for up to 512 bytes of raw packet filtering. The 
> direct approach is:
> 
>    # ethtool -N eth0 flow-type raw-fltr N [m N] action N
> 
> where N would be allowed to be 512 bytes. Would that be acceptable? Any 
> concerns regarding netlink or other user-space/kernel comm?

We need more info about the use case and what this will achieve.
Asking if you can extend uAPI is like asking if you can walk in
the street. Sometimes you can sometimes you can't. All depends
on context, so start with the context, please.