Re: [PATCH net-next 1/3] net: macb: Make sure clk_init_data is fully initialized

From: "Théo Lebrun" <theo.lebrun@bootlin.com>
To: "Geert Uytterhoeven" <geert+renesas@glider.be>,
	"Conor Dooley" <conor.dooley@microchip.com>,
	"Andrew Lunn" <andrew+netdev@lunn.ch>,
	"David S . Miller" <davem@davemloft.net>,
	"Eric Dumazet" <edumazet@google.com>,
	"Jakub Kicinski" <kuba@kernel.org>,
	"Paolo Abeni" <pabeni@redhat.com>,
	"Heiner Kallweit" <hkallweit1@gmail.com>,
	"Russell King" <linux@armlinux.org.uk>,
	"Neil Armstrong" <neil.armstrong@linaro.org>,
	"Kevin Hilman" <khilman@baylibre.com>,
	"Jerome Brunet" <jbrunet@baylibre.com>,
	"Martin Blumenstingl" <martin.blumenstingl@googlemail.com>
Cc: <netdev@vger.kernel.org>, <linux-arm-kernel@lists.infradead.org>,
	<linux-amlogic@lists.infradead.org>, <linux-clk@vger.kernel.org>
Subject: Re: [PATCH net-next 1/3] net: macb: Make sure clk_init_data is fully initialized
Date: Mon, 24 Aug 2026 18:03:32 +0200	[thread overview]
Message-ID: <DKXAUOKYDIWV.B30CB2QWDDXQ@bootlin.com> (raw)
In-Reply-To: <00772e2fb1f8433a5d6c47dbd28cb4149495e1ab.1787240118.git.geert+renesas@glider.be>

Hello Geert,

On Fri Aug 21, 2026 at 12:07 PM CEST, Geert Uytterhoeven wrote:
> The clk_init_data structure contains several mutually-exclusive members
> for different methods to specify the possible parents of a clock,
> prompting drivers to initialize only the members they need.  However,
> not initializing all members may cause subtle issues, which are only
> exposed when CONFIG_INIT_STACK_ALL_PATTERN or CONFIG_INIT_STACK_NONE is
> enabled.
>
> Make sure all members are fully initialized, to avoid such bugs, and to
> prevent future breakage when converting drivers to a different method
> for specifying the parents.
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
> Compile-tested only.
> ---
>  drivers/net/ethernet/cadence/macb_main.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
> index 1476bce77f34d2a5..319e43098f57ed7b 100644
> --- a/drivers/net/ethernet/cadence/macb_main.c
> +++ b/drivers/net/ethernet/cadence/macb_main.c
> @@ -5376,7 +5376,7 @@ static int fu540_c000_clk_init(struct platform_device *pdev, struct clk **pclk,
>  			       struct clk **hclk, struct clk **tx_clk,
>  			       struct clk **rx_clk, struct clk **tsu_clk)
>  {
> -	struct clk_init_data init;
> +	struct clk_init_data init = {};
>  	int err = 0;
>  
>  	err = macb_clk_init_dflt(pdev, pclk, hclk, tx_clk, rx_clk, tsu_clk);

Reviewed-by: Théo Lebrun <theo.lebrun@bootlin.com>

I cannot give you a Tested-by because this triggers only on
sifive,fu540-c000-gem compatible matching upstream devicetrees
sifive/hifive-{unleashed,unmatched}-a00.dts

Thanks,

--
Théo Lebrun, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com