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Message-ID: <c6cd675b-d770-fe11-bc71-a6b7cefd01e6@gmail.com>
Date:   Thu, 2 Sep 2021 16:21:48 -0700
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Subject: Re: [RFC PATCH net-next 2/3] net: dsa: destroy the phylink instance
 on any error in dsa_slave_phy_setup
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To:     Vladimir Oltean <vladimir.oltean@nxp.com>, netdev@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Andrew Lunn <andrew@lunn.ch>,
        Heiner Kallweit <hkallweit1@gmail.com>,
        Russell King <linux@armlinux.org.uk>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Vivien Didelot <vivien.didelot@gmail.com>,
        Vladimir Oltean <olteanv@gmail.com>,
        linux-kernel@vger.kernel.org,
        Linus Walleij <linus.walleij@linaro.org>,
        =?UTF-8?Q?Alvin_=c5=a0ipraga?= <alsi@bang-olufsen.dk>,
        ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
        kernel-team <kernel-team@android.com>,
        Len Brown <lenb@kernel.org>
References: <20210901225053.1205571-1-vladimir.oltean@nxp.com>
 <20210901225053.1205571-3-vladimir.oltean@nxp.com>
From:   Florian Fainelli <f.fainelli@gmail.com>
In-Reply-To: <20210901225053.1205571-3-vladimir.oltean@nxp.com>
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On 9/1/2021 3:50 PM, Vladimir Oltean wrote:
> DSA supports connecting to a phy-handle, and has a fallback to a non-OF
> based method of connecting to an internal PHY on the switch's own MDIO
> bus, if no phy-handle and no fixed-link nodes were present.
> 
> The -ENODEV error code from the first attempt (phylink_of_phy_connect)
> is what triggers the second attempt (phylink_connect_phy).
> 
> However, when the first attempt returns a different error code than
> -ENODEV, this results in an unbalance of calls to phylink_create and
> phylink_destroy by the time we exit the function. The phylink instance
> has leaked.
> 
> There are many other error codes that can be returned by
> phylink_of_phy_connect. For example, phylink_validate returns -EINVAL.
> So this is a practical issue too.
> 
> Fixes: aab9c4067d23 ("net: dsa: Plug in PHYLINK support")
> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian