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Date:   Thu, 22 Jun 2023 21:54:53 +0200
From:   Sabrina Dubroca <sd@queasysnail.net>
To:     Carlos Fernandez <carlos.fernandez@technica-engineering.de>
Cc:     Jakub Kicinski <kuba@kernel.org>,
        "davem@davemloft.net" <davem@davemloft.net>,
        "edumazet@google.com" <edumazet@google.com>,
        "pabeni@redhat.com" <pabeni@redhat.com>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v3] net: macsec SCI assignment for ES = 0
Message-ID: <ZJSnDZL-0hLxbDje@hog>
References: <20230620091301.21981-1-carlos.fernandez@technica-engineering.de>
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Hi Carlos,

2023-06-22, 11:49:44 +0000, Carlos Fernandez wrote:
> Hi Jakub,
> 
> Also, about the double look up:
> I know it's there, but I tried to only change the function that returns the correct SCI in every case. Also, it should be a 1 and only item list. I do not think this should be dangerous or slow.

Why is it a 1 item list? Even if that was guaranteed to be true in
normal conditions, we could have a situation where lots of MACsec
SecYs and RXSCs are set up, and packets start hitting this loop.


And could you quote the correct section of 802.1AE? I can't find the
reference for the behavior you're implementing in this patch. All I
can find is (from section 9.5):

    The ES bit is clear if the Source Address is not used to determine the SCI.

    The SC bit shall be clear if an SCI is not present in the SecTAG.

which doesn't say anything about how to interpret both bits being
clear.


(and please don't top-post)


Thanks,

-- 
Sabrina