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Date:   Thu, 05 Aug 2021 10:02:41 +0100
Message-ID: <87v94kb6xa.wl-maz@kernel.org>
From:   Marc Zyngier <maz@kernel.org>
To:     Saravana Kannan <saravanak@google.com>
Cc:     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>,
        Neil Armstrong <narmstrong@baylibre.com>,
        Kevin Hilman <khilman@baylibre.com>, kernel-team@android.com,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v1 0/3] Clean up and fix error handling in mdio_mux_init()
In-Reply-To: <20210804214333.927985-1-saravanak@google.com>
References: <20210804214333.927985-1-saravanak@google.com>
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Hi Saravana,

On Wed, 04 Aug 2021 22:43:29 +0100,
Saravana Kannan <saravanak@google.com> wrote:
> 
> This patch series was started due to -EPROBE_DEFER not being handled
> correctly in mdio_mux_init() and causing issues [1]. While at it, I also
> did some more error handling fixes and clean ups. The -EPROBE_DEFER fix is
> the last patch.
> 
> Ideally, in the last patch we'd treat any error similar to -EPROBE_DEFER
> but I'm not sure if it'll break any board/platforms where some child
> mdiobus never successfully registers. If we treated all errors similar to
> -EPROBE_DEFER, then none of the child mdiobus will work and that might be a
> regression. If people are sure this is not a real case, then I can fix up
> the last patch to always fail the entire mdio-mux init if any of the child
> mdiobus registration fails.
> 
> Cc: Marc Zyngier <maz@kernel.org>
> Cc: Neil Armstrong <narmstrong@baylibre.com>
> Cc: Kevin Hilman <khilman@baylibre.com>
> [1] - https://lore.kernel.org/lkml/CAGETcx95kHrv8wA-O+-JtfH7H9biJEGJtijuPVN0V5dUKUAB3A@mail.gmail.com/#t
> 
> Saravana Kannan (3):
>   net: mdio-mux: Delete unnecessary devm_kfree
>   net: mdio-mux: Don't ignore memory allocation errors
>   net: mdio-mux: Handle -EPROBE_DEFER correctly
> 
>  drivers/net/mdio/mdio-mux.c | 37 ++++++++++++++++++++++++-------------
>  1 file changed, 24 insertions(+), 13 deletions(-)

Thanks for this. I've just gave it a go on my test platform, and this
indeed addresses the issues I was seeing [1].

Acked-by: Marc Zyngier <maz@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>

	M.

[1] https://lore.kernel.org/r/87im0m277h.wl-maz@kernel.org

-- 
Without deviation from the norm, progress is not possible.