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Date:   Fri, 20 Aug 2021 19:54:34 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Saravana Kannan <saravanak@google.com>
Cc:     Alvin =?utf-8?Q?=C5=A0ipraga?= <ALSI@bang-olufsen.dk>,
        Vladimir Oltean <olteanv@gmail.com>,
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        Jakub Kicinski <kuba@kernel.org>,
        "David S. Miller" <davem@davemloft.net>,
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        Vivien Didelot <vivien.didelot@gmail.com>,
        Frank Rowand <frowand.list@gmail.com>,
        Rob Herring <robh+dt@kernel.org>
Subject: Re: [PATCH net] net: dsa: sja1105: fix use-after-free after calling
 of_find_compatible_node, or worse
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> 3. If dsa_register_switch() fails, we can't defer the probe (because
> it already succeeded). But I'm not sure if it's a likely error code.

That is not a safe assumption. The tagging driver can be a module, and
not be loaded yet. So we defer probing to allow it to load.

Ethernet switches can be a big graph of parts, not a nice tree of
parts.

    Andrew