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Date:   Fri, 14 May 2021 18:58:31 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Ansuel Smith <ansuelsmth@gmail.com>
Cc:     Vivien Didelot <vivien.didelot@gmail.com>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Vladimir Oltean <olteanv@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Heiner Kallweit <hkallweit1@gmail.com>,
        Russell King <linux@armlinux.org.uk>,
        "open list:NETWORKING DRIVERS" <netdev@vger.kernel.org>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>,
        open list <linux-kernel@vger.kernel.org>
Subject: Re: [RFC PATCH net-next v5 18/25] net: dsa: qca8k: dsa: qca8k:
 protect MASTER busy_wait with mdio mutex
Message-ID: <YJ6sNxsSyK9BNaLt@lunn.ch>
References: <20210511020500.17269-1-ansuelsmth@gmail.com>
 <20210511020500.17269-19-ansuelsmth@gmail.com>
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On Tue, May 11, 2021 at 04:04:53AM +0200, Ansuel Smith wrote:
> MDIO_MASTER operation have a dedicated busy wait that is not protected
> by the mdio mutex. This can cause situation where the MASTER operation
> is done and a normal operation is executed between the MASTER read/write
> and the MASTER busy_wait. Rework the qca8k_mdio_read/write function to
> address this issue by binding the lock for the whole MASTER operation
> and not only the mdio read/write common operation.
> 
> Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew