From mboxrd@z Thu Jan  1 00:00:00 1970
From: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Subject: Re: [PATCH] net: dev_forward_skb(): Scrub packet's per-netns info
 only when crossing netns
Date: Thu, 15 Mar 2018 18:11:47 +0200
Message-ID: <20180315181147.0f7c21e7@halley>
References: <58e67195-56f6-4d01-8747-f8322a382358@default>
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Cc: <mrv@mojatatu.com>, <netdev@vger.kernel.org>,
        <daniel@iogearbox.net>, <davem@davemloft.net>,
        <linux-kernel@vger.kernel.org>, <yuval.shaia@oracle.com>,
        <idan.brown@oracle.com>
To: Liran Alon <liran.alon@oracle.com>
Return-path: <linux-kernel-owner@vger.kernel.org>
In-Reply-To: <58e67195-56f6-4d01-8747-f8322a382358@default>
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On Thu, 15 Mar 2018 08:01:03 -0700 (PDT) Liran Alon <liran.alon@oracle.com> wrote:
> 
> I still think that default behavior should be to zero skb->mark only when skb
> cross netdevs in different netns.

But the previous default was scrub the mark in *both* xnet and non-xnet
situations.

Therefore, there might be users which RELY on this (strange) default
behavior in their same-netns-veth-pair setups.
Meaning, changing the default behavior might break their apps relying on
the former default behavior.

This is why the "disable mark scrubbing in non-xnet case" should be opt-in.

Regards,
Shmulik