From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jamal Hadi Salim <jhs@mojatatu.com>
Subject: Re: [PATCH iproute2 net 3/8] tc/pedit: Introduce 'add' operation
Date: Sun, 23 Apr 2017 13:44:51 -0400
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References: <20170423125356.1298-1-amir@vadai.me>
 <20170423125356.1298-4-amir@vadai.me>
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Cc: netdev@vger.kernel.org, Or Gerlitz <ogerlitz@mellanox.com>
To: Amir Vadai <amir@vadai.me>,
        Stephen Hemminger <stephen@networkplumber.org>
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Thanks for the excellent work.

On 17-04-23 08:53 AM, Amir Vadai wrote:
> This command could be useful to increase/decrease fields value.
>

Does this contradict the "retain" feature? Example rule to
retain the second nibble but set the first to 0xA
(essentially it X-ORs):
tc filter add dev lo parent ffff: protocol ip prio 10 \
u32 match ip dst 127.0.0.1/32 flowid 1:1 \
action pedit munge offset 0 u8 set 0x0A retain 0xF0

Mostly curious about hardware handling.

cheers,
jamal