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Date:   Sat, 28 Nov 2020 01:39:12 +0100
From:   Andrew Lunn <andrew@lunn.ch>
To:     Vladimir Oltean <olteanv@gmail.com>
Cc:     Jakub Kicinski <kuba@kernel.org>,
        George McCollister <george.mccollister@gmail.com>,
        Vivien Didelot <vivien.didelot@gmail.com>,
        Florian Fainelli <f.fainelli@gmail.com>,
        "David S . Miller" <davem@davemloft.net>, netdev@vger.kernel.org,
        "open list:OPEN FIRMWARE AND..." <devicetree@vger.kernel.org>
Subject: Re: [PATCH net-next v2 2/3] net: dsa: add Arrow SpeedChips XRS700x
 driver
Message-ID: <20201128003912.GA2191767@lunn.ch>
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> This means, as far as I understand, 2 things:
> 1. call_netdevice_notifiers_info doesn't help, since our problem is the
>    same
> 2. I think that holding the RTNL should also be a valid way to iterate
>    through the net devices in the current netns, and doing just that
>    could be the simplest way out. It certainly worked when I tried it.
>    But those could also be famous last words...

DSA makes the assumption it can block in a notifier change event.  For
example, NETDEV_CHANGEUPPER calls dsa_slave_changeupper() which calls
into the driver. We have not seen any warnings about sleeping while
atomic. So maybe see how NETDEV_CHANGEUPPER is issued.

	Andrew